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The urothelium: a multi-faceted barrier against a harsh environment

Nazila V. Jafari, Jennifer L. Rohn

Mucosal Immunology · 2022 · Review · CC BY

doi:10.1038/s41385-022-00565-0

Abstract

All mucosal surfaces must deal with the challenge of exposure to the outside world. The urothelium is a highly specialized layer of stratified epithelial cells lining the inner surface of the urinary bladder, a gruelling environment involving significant stretch forces, osmotic and hydrostatic pressures, toxic substances, and microbial invasion. The urinary bladder plays an important barrier role and allows the accommodation and expulsion of large volumes of urine without permitting urine components to diffuse across. The urothelium is made up of three cell types, basal, intermediate, and umbrella cells, whose specialized functions aid in the bladder's mission. In this review, we summarize the recent insights into urothelial structure, function, development, regeneration, and in particular the role of umbrella cells in barrier formation and maintenance. We briefly review diseases which involve the bladder and discuss current human urothelial in vitro models as a complement to traditional animal studies.

Full text

From PubMed Central, U.S. National Library of Medicine, as current on Oct 24, 2026. Paragraph numbers are ours, so an answer can point at one.

Introduction

The epithelial cells that line mucosal surfaces form a barrier between the internal and external environments with a continuous layer of tightly linked cells. The harsh conditions at the external-facing surfaces of organs and tissues require a structurally robust epithelium that maintains a barrier to the outer environment. Mucosal epithelia at sites such as the gastrointestinal (GI) tract, the respiratory and the genitourinary tract must strike a balance between facilitating a selective transport while also forming a barrier with restricted paracellular transport.

Most epithelia share common core functions including protection, sensation, transport, secretion, clearance, and repair, and they protect organs by providing a unique interface for each organ to inhabit. They also form diffusion barriers that separate distinct compartments, often from the external environment, with diverse permeability, which can be classified as either leaky or tight. Epithelial cells sense their environment, and many facilitate active and passive transcellular and passive paracellular transport. Ions, water, and other substances transported by epithelia aid luminal surface hydration, while mucins assist in surface lubrication, supporting mucosal homeostasis. Fronting such a hostile environment, the epithelia must inevitably regenerate. While the location of the stem cell compartment varies among epithelia, it is often located at the base, allowing cell migration toward the lumen.

The urothelium (sometimes referred to as uroepithelium) is a stratified, transitional epithelium that lines the renal pelvis, ureters, bladder, and proximal urethra. This mucosal surface layer plays an important barrier role, preventing absorption of urine’s toxic substances such as acid and urea and defending against pathogen entry from the external environment–. The urothelium consists of three cell types: basal, intermediate, and superficial cells, also known as umbrella cells or facet cells. The basal cells are the most undifferentiated urothelial cell type, located at the basement membrane of the lumen and serving a progenitor role. The intermediate cells are highly proliferative, forming multiple cell layers depending on the species. In times of injury or infection, intermediate cells are responsible for rapidly regenerating the urothelium. On the apical surface, fully differentiated umbrella cells are responsible for maintaining the impermeability and high-resistance barrier function of the urothelium,,. In this review we will discuss the structure and function of the urothelium and recent advances in developing in vitro models to study host-pathogen interaction. We focus on human systems and, if not otherwise indicated, statements refer to the human context.

The urothelium: structure and function

Here, we discuss in detail the three main cell types that comprise the bladder urothelium.

Basal cells

The basal cell layer is positioned along the basement membrane (Fig. 1); they are the smallest of the urothelial cells (5–10 µm in diameter) but constitute the most abundant cell population in adult urothelium. They are attached directly to the basement membrane via hemidesmosomes– and to the overlying intermediate cells by desmosomes. As discussed in more detail in a later section, it has been proposed that basal cells potentially harbor a subset of urothelial stem cells providing lifelong regeneration of the urothelium. In a study using single-cell transcriptomic analysis of mouse bladder urothelium, a cluster of cells was distinguished expressing the marker gene Abnormal Spindle Microtubule Assembly (ASPM); genome-wide analysis suggested this ASPM+ expression could implicate these basal cells as stem/progenitor cells. However, studies also suggest that both basal and intermediate cells are undifferentiated precursor cells with the ability to undergo a programmed differentiation into umbrella cells during development and in the adult urothelium,.

Basal cells are distinguished by expression of high levels of cytokeratin-5 (CK5), p63, and the signalling molecule Sonic hedgehog (Shh). Together with intermediate cells, they express CK17 but are negative for uroplakins (UPK) and CK20 (Fig. 2).

Intermediate cells

The cell layer directly above the basal cells is referred to as the intermediate cell layer and depending on the species, this layer can range from one to several layers thick (Fig. 1) (e.g., there are approximately five intermediate cell layers in humans and one in rodents),. The intermediate cells are larger in diameter than basal cells (∼20 μm) and are attached to the adjacent cell layers and one another via desmosomes,. They differ from the basal cells based on their expression of UPK and lack of CK5,, similar to umbrella cells (UPK+, CK5−), but unlike umbrella cells they additionally express p63 (UPK+, p63+, CK5−) (Fig. 2). Basal and intermediate cells also express CK17 which is completely absent in umbrella cells. Although intermediate cells express tight junction-associated proteins such as claudins, and the E-cadherin epithelial cell adhesion protein, they do not seem to form morphologically discernible tight or adherens junctions.

Umbrella cells

The superficial umbrella cells form a single layer of terminally differentiated and highly specialized cells that directly face the luminal surface (Fig. 1). These cells are large, hexagonal in shape, highly polarized, and in some species, multinucleated (e.g., rat and guinea pig). Umbrella cells are long-lived (∼200 days in rodents) and can range in size from 25 to 250 μm depending on the bladder distension level,. In the relaxed state, superficial cells form a dome-shaped structure at the apical pole, and can also cover multiple underlying intermediate cells, hence the name umbrella cells,. In contrast, when the bladder is filled, they become large and flattened (see section: maintaining the barrier during mechanical changes). Umbrella cells are attached to sub-superficial cell layers via desmosomes, while tight junctions localized between superficial cells aid in forming the high-resistance barrier function,. The umbrella cell layer is the only urothelial layer that forms detectable tight and adherens junctions, which are principally responsible for barrier function by sealing the intercellular space between the adjacent cells. Urothelial tight junctions are comprised of tight junction protein 1 (ZO-1), occludin, claudin-4, 8, and 12,.

Four major UPK are synthesized by umbrella cells in mammals, which include UPK1A, UPK1B, UPK2, and UPK3A. They comprise a small family of transmembrane proteins and form a hexagonal crystalline lattice at the apical membrane,,. Together, the urothelial plaque and junctional complexes establish high electrical resistance and a highly effective permeability barrier, both of which regulate water and ion passage from urine to the underlying tissue,,,. Single-cell transcriptomic analysis of mouse urothelium revealed a novel cluster of cells enriched for Plxna4; as these cells also highly expressed UPK3, they appeared to be umbrella cells. However, they were negative for CK20, which is a urothelial differentiation marker. The authors therefore concluded that the Plxna4+ urothelial cell cluster is a special type of urothelial cells.

Another distinguishing feature of umbrella cells is the presence of subapical discoidal/fusiform-shaped vesicles (DFVs) contributing to the plasticity in urothelial cell surface area through a regulated process of endocytosis/exocytosis,,. A major functional role of the DFVs is to fuse with the apical membrane of the umbrella cells and release UPK and other proteins in response to bladder filling. This adjusts the permeability barrier and allows the expansion of the urothelium–. During emptying of the bladder, the reverse process occurs, causing the decrease of urothelial surface area. Umbrella cells also express high concentrations of CK20, this protein contributes to a cytokeratin network located below the apical surface of the superficial cells which guides DFVs to the surface.

In addition to the literature discussed above, the Human Protein Atlas also contains useful and evolving information about the urinary bladder-specific proteome (Human Protein Atlas proteinatlas.org).

Urothelial development

Although the term “urothelium” is used to describe the epithelial lining of both upper and lower urinary tracts, the ontogeny of the urothelium varies. The proximal urethral and bladder urothelium is derived from the endoderm, whereas the urothelia lining the ureters and renal pelvis are mesoderm-derived,. Irrespective of the origin, the primordial urothelium starts off as a single layer of immature, cuboidal epithelial cells. These cells undergo cell division under the direction of ligands produced by the stroma, and ultimately differentiate into three defined layers of basal, intermediate and umbrella cells as discussed above,–.

Regeneration and repair of the urothelium

Under homeostatic conditions, the adult urothelium is mitotically quiescent, and turnover is very slow,,. However, in response to injury, there is a marked upregulation in urothelial proliferation resulting in rapid repair and regeneration, terminating with a completely restored, morphologically normal appearance within a few days to weeks,,,,,–. Urothelial renewal depends on input from both the stroma and the urothelium; required signalling pathways include those regulated by bone morphogenetic protein 4 (BMP4), non-canonical and canonical Wnt, Delta-Notch, the epithelial cell-specific transcription factor ELF3, several growth factors, retinoids, Sonic hedgehog (Shh and GLI1), and TP63 (tumor promoter 63 kDa, p63, or Trp63),,,,–.

Following acute urothelial injuries by chemical exposure (e.g., chitosan, cyclophosphamide, protamine sulfate, saccharin), surgical damage (for example during augmentation cystoplasty or focal mucosal resection) or infection with uropathogenic microbes, the urothelium starts repairing almost immediately. Uropathogenic Escherichia coli (UPEC), the primary cause of urinary tract infection (UTI), initiates a UTI using FimH located at the tip of the Type 1 pili, mediating adhesion to N-linked carbohydrates covalently attached to UPK1A proteins expressed at the apical surface of umbrella cells. FimH-mediated interactions with the urothelium stimulate umbrella cell exfoliation which in turn prompts proliferation of the remaining urothelial cells and, ultimately urothelial regeneration.

The basal cell layer in other stratified epithelial cells serves as a stem cell population to maintain epidermal growth and renewal. Therefore, urothelial progenitors may also be located in the basal cell layer (Fig. 2). Basal cells express high levels of CK5, but studies have identified a subset of basal cells also expressing CK14. Under homeostatic conditions, these cells are the only mitotically active cells and have been identified as long-term label-retaining cells. Several studies have investigated urothelial renewal during homeostasis and regeneration following insults of a chemical, surgical or bacterial nature. Papafotiou et al. identified a rare subset of basal cells in mice embryonic bladder that expresses Krt14 (encoding CK14) and exhibits progenitor properties, based on genetic fate-mapping in vivo and greater self-renewal capacity in vitro. This study revealed that a single round of cyclophosphamide-induced injury stimulates a local proliferation of CK14+ basal cells; however, after several consecutive treatments, CK14+ cells were found in all three urothelial layers. Another mouse study identified a transient progenitor population during embryogenesis but reported that the uroplakin-positive intermediate cells were the source of both intermediate and umbrella cells in juvenile and adult bladders. Similarly, a study on the developing mouse ureter concluded that the umbrella and basal cells of the primordial urothelium are mainly derived from uroplakin-positive intermediate progenitor cells.

A genetic fate-mapping study of intrarenal urothelial development in mice revealed that progenitor cells expressing Krt5 (encoding CK5) can give rise to uroplakin-expressing cells. However, they concluded that the differentiation of CK5+ cells into uroplakin-expressing cells was chiefly restricted to early time periods, as juvenile and adult CK5+ cells showed lineage restriction. Other mouse model studies have indicated that CK5+CK14+ basal cells expand in response to urothelial injuries and therefore are the progenitor cells of all urothelial lineages,. Schafer et al. showed that in a mouse surgical bladder injury model following augmentation cystoplasty, CK5-expressing basal cells repopulate all lineages of the urothelium. However, the repair was surgical procedure-dependent, as repair of focal mucosal defects instead employed CK5 basal cell repopulation in parallel with intermediate cells, which express UPII to regenerate themselves and also give rise to umbrella cells in neotissues.

Several studies also observed that in response to UPEC infection, the CK5+ and Shh+ basal cells, and possibly intermediate cells sharing the same phenotype, proliferate and give rise to other cell types,,. Whether the results of these rodent models of studies are relevant to human urothelial development/repair remain unknown, but they do indicate that the type and extent of injury likely defines the urothelial progenitor populations that are responsible for regeneration.

Urothelial differentiation markers

Although there are many potential urothelial differentiation markers, only a relatively small number have been classified and of these, most are in mice. Such markers include UPK, cytokeratins, and signalling/transcription factors such as Shh, Tp63, and FOX2A (Forkhead box protein A2). In this review we discuss UPK and cytokeratins.

Uroplakins

As mentioned above, UPK are differentiation-specific tetraspanin membrane proteins mainly associated with the umbrella cells. To date, five UPK have been identified including UPK1A, UPK1B, UPK2, UPK3A, and UPK3B. They are the major constituents of the urothelial plaques and asymmetric unit membrane (AUM), the characteristic apical membrane of the superficial layer,. Initially, UPK1A dimerizes with UPK2, and UPK1B with UPK3A and 3B forming heterodimers–. The importance of dimerization is underscored by the inability of the UPKs, when expressed individually, to exit the endoplasmic reticulum and reach the membrane. The heterotetradimers are formed following the interaction of UPK2 and UPK3A moieties of the heterodimers. Following assembly within the endoplasmic reticulum and the Golgi, six heterotetradimers arranged in inner and outer rings form a 16 nm AUM particle or plaque (Fig. 3), packaged into DFVs and delivered to the apical membrane. The AUM particles are also capable of changing their arrangement in response to mechanical changes such as bladder expansion and contraction so therefore undergo high renewal. The urothelial plaque decorates up to 90% of the luminal surface and confers transcellular resistance, restricting permeability to water and solutes, and toxins,.

All UPKs have extensive exoplasmic domains resulting in thickening of the outer leaflet of the membrane, a feature that contributes to the permeability function of the urothelium. The role of UPK in urothelial barrier function has been demonstrated by the fact that UPK3A knockout mice showed decreased urothelial barrier function, including increased water and urea permeability.

Although UPK are considered to be markers for umbrella cells across species, in mice there is a population of intermediate cells that express UPK, in particular UPK3A,. These cells are usually located in the layer of cells immediately below the umbrella cells when the superficial layer is damaged. As another exception, UPK2 is expressed in both umbrella and intermediate cells of the mouse bladder. In the human bladder, all UPKs are expressed specifically in the urothelium except UPK1B. There is also an increasing appreciation that UPK are expressed in non-urothelial cells–.

Cytokeratins

Urothelial distension and the increase of luminal surface area caused by bladder filling require a resilient mechanical support to resist extreme stretching forces. Cytokeratins are the best candidates among cytoskeletal filaments to protect urothelial cells against such mechanical stress,. Unlike other cytoskeletal filaments, the elasticity of the cytokeratins increases in response to tension. Once the strain is released, they are able to recover almost immediately and regain their original shape.

The cytokeratins may be regarded as differentiation markers because cytokeratin isotypes are expressed by almost all epithelial cell lineages, and distinct cytokeratin expression profiles are associated with particular epithelial differentiation pathways. Furthermore, the expression of certain cytokeratin isotypes may be associated with a specific maturation stage. Therefore, these different aspects need to be considered when interpreting cytokeratin expression, which may be modulated according to the differentiation and/or pathological status of a tissue.

In humans, cytokeratins consist of more than 20 isotypes of proteins including type I (CK9-CK20) and type II (CK1-CK8). In all epithelial cells, intermediate filaments are composed of at least one type I and one type II cytokeratin, forming coiled-coil heterodimers which are expressed in a tissue- and differentiation-dependent manner,. The ratio of type I to type II is always 1:1, irrespective of the number of cytokeratins expressed in a particular epithelial cell,.

The urothelium is reported to express numerous cytokeratins including CK4, CK5, CK7, CK8, CK13, CK14, CK17, CK18, CK19, and CK20,,–. Cytokeratin expression in the urothelium varies and depends on its location. In mice, CK10 is expressed only in the urethral urothelium, while CK6 in humans is exclusively expressed in the renal pelvis urothelium. Moreover, cytokeratin expression or distribution differs between species,. In mice, CK5, CK14, CK20, and to lesser extent CK17 are the markers most often used to describe urothelial differentiation,,,. CK20 is only expressed in mouse umbrella cells and CK7 is reported to be solely expressed by a population of intermediate cells, although there are studies showing that CK7 is expressed throughout the mouse urothelium. While CK14 is only expressed in a small population of basal cells, CK5 expression is detected in all cells located in the basal layer including those that are CK14 positive,,,. In addition, CK5 is expressed by most intermediate cells apart from cells that express UPK3A,.

In normal adult human urothelium, CK7, CK8, CK18, and CK19 expression has been observed throughout all urothelial cell layers. While CK17 and CK5 are basally expressed, CK20 is associated with umbrella cells,,. Although CK13 is present in basal and intermediate cell layers, it is used as marker of the switch from basal cells to differentiated urothelial transitional cells. Studies have reported that normal human cells in culture exhibit late/terminal cytodifferentiation when activated with PPARγ agonists, promoting a switch from a non-differentiated phenotype (CK14+, CK13−, CK20−) to a terminally differentiated transitional phenotype (CK14−, CK13+, CK20+),.

The urothelial barrier

The bladder urothelium is exposed to great osmotic and chemical gradients and mechanical changes as urine is produced, transported, stored, and voided from the bladder. Therefore, the urothelial barrier function is essential to maintain a high-resistance barrier for prolonged periods to the outside environment which includes excess water, ions, solutes, and metabolic waste products, preventing the diffusion of harmful urinary products into the underlying tissues and moreover, defending against pathogens. This barrier is complex and includes three components: the apical, the lateral, and the basal barrier. The apical membrane barrier is composed of UPK, in which AUM particles are assembled into hexagonal plaques forming a flexible apical barrier. The umbrella cell tight junctions form the lateral barrier, and the basal barrier consists of group of proteins including cadherin, claudins, and laminins.

Urothelial glycocalyx

The glycocalyx is a dense, gel-like meshwork that forms a physical barrier at the apical membrane of the umbrella cell layer,. Although prominent in enterocytes lining the gut and in endothelial cells, only a thin layer has been visualized in the urothelium using transmission electron microscope (TEM),,,. The glycocalyx comprises membrane-bound glycoproteins and glycolipids, along with soluble components including galectins and proteoglycans. The glycosaminoglycans (GAG), composed of unbranched carbohydrates with repeating disaccharide units, are attached to a core protein to form a proteoglycan. The GAG layer consists mainly of heparin sulfate, dermatan sulfate, chondroitin sulfate, hyaluronic acid, and keratan sulfate. Chondroitin sulfate and hyaluronic acid, the two main components, play a central role in forming the barrier and in antibacterial defence. There is convincing evidence that the glycocalyx may have intrinsic, nonspecific, and anti-adherence properties that protect against pathogens,.

The apical junctional complex and regulation of paracellular permeability

Apical junctions are specialized epithelial structures; as a hallmark of polarized epithelial cells, they play a crucial role in regulating paracellular transport,,. Apical junctional complex (Fig. 4) is comprised of three components: (i) the apical tight junction or zonula occludens, which is formed by transmembrane claudins together with other membrane and cytoplasmic proteins, linked to the actin cytoskeleton; (ii) the zonula adherens (subjacent adherens junction) which is comprised of cadherins and associated catenins tethering the adherens junctions to the actin cytoskeleton; and (iii) the desmosomes or macula adherens, comprised of cadherin-like molecules (desmogleins and democollins) and their associated cytoplasmic proteins that mediate the desmosomes attachment to the intermediate filament cytoskeleton,–.

Epithelial cell membranes form a barrier to macromolecules and hydrophilic solutes including ions and water; however, these molecules can potentially navigate the paracellular pathway at the cell junctions. The adherens junctions (AJ) and desmosomes are crucial to link intercellular adhesion to the actin or intermediate filaments cytoskeletons and connect adjacent epithelial cells together. Nevertheless, these junctions do not seal the paracellular pathway; this pathway is instead controlled by tight junctions (TJ), the component of the apical junctional complex bordering the lumen.

The TJ is located at the apex of two adjacent cells, forming a continuous ring. TJs have two basic functions; first, they act as a “fence” separating the apical and basolateral membrane domains; in doing so, they restrict the lateral diffusion of membrane proteins and lipids–. Second, they possess a “gate” function which is responsible for regulating the paracellular diffusion of ions and other molecules between cells–. The TJ is composed of two families of transmembrane proteins, the claudins and occludins, which form homotypic claudin-claudin and occludin-occludin complexes between cells. The complementary assembly of TJ strands between adhering cells creates a complex network of gaps and pores through which different ions and solutes are thought to diffuse,–. Diffusion in the paracellular pathway varies with claudin types and is gated via different amino acids in the extracellular loops of claudins. The combination of claudin isoforms specifies the permeability of ions of different size and charge, which classifies the claudins into either “pore forming” or “barrier forming”,.

In the urothelium, umbrella cells are characterized by apical expression of transmembrane uroplakins that contribute to transcellular barrier function,, while the paracellular barrier is maintained by intercellular tight junctions with claudin proteins defining the paracellular permeability,. The permeability across the TJ differs in a cell type-specific manner. In the proximal tubule of the kidney, for example, the transepithelial electrical resistance (TEER) is ~200 Ω cm2, while the urothelial TEER is ~75,000 Ω cm2 in the presence of amiloride, which blocks transcellular sodium transport.

Claudin 1 is ubiquitously expressed in most tissues and mainly acts as a barrier builder,. It is found in human urothelium,, along the basal and intermediate cell membrane but it is particularly enriched in the basal surface of the basal cell layer–. Claudin 2 forms a high-conductance cation-selective pore,– and is detected in the proximal tubule of the kidney and in the intestinal crypts, both of which are considered “leaky” epithelia–. Interestingly, in mouse bladder, claudin 2 is expressed in all three cell layers. In the human urothelium, the expression of claudin 3 is necessary for the development of the umbrella cell terminal tight junction. It is a ubiquitously expressed barrier-forming claudin which is restricted to the apicolateral plasma membrane of the umbrella cells in human,, and mouse urothelium. Several studies indicate that claudin 4 is barrier-forming– and is present in human and rodent urothelium, with its expression higher in umbrella and intermediate layers compared with the basal cells,,–,,. In humans, claudin 7 is distributed similarly to claudin 4–, with the exception of umbrella cells,,. Claudin 8 is another barrier-forming claudin shown to localize primarily in the TJs of the umbrella cells in human and rodent bladders,,. Zonula occludens-1 (ZO-1), also known as tight junction protein-1 and integral protein occludin, is also present at the TJ of umbrella cells,,. Of note, there are reports indicating regional differences in the distribution of TJ-associated proteins. For instance, CLDN1 and CLDN4 mRNA levels are significantly higher in the human bladder trigone than in the dome.

Water and urea transport across the urothelium

The apical membrane of umbrella cells along with the TJ form a relatively impermeable barrier to the unrestricted diffusion of solutes and water, but there is ion flux across the epithelium,. Sodium is the primary transported ion, by a mechanism modulated by several molecular and physical factors,–. Studies have shown that rabbit urinary bladder exhibits an extremely low permeability to ions with a TEER above 20,000 Ω cm2 in the quiescent state and ~75,000 Ω cm2 when transcellular sodium transport is blocked,. In addition, lipid bilayers have inherently low permeability to ions, so their diffusion across the membrane depends on the presence of ion channels. It has been proposed that the mechanosensitive ion channels located in the apical membrane of umbrella cells which support transepithelial sodium ion flux may have a sensory role in normal micturition.

The urothelium also expresses several aquaporins (AQPs), a family of 13 members that transport water or small solutes such as NH3, CO2, glycerol, and urea across cell membranes,. The AQPs can be divided into two subfamilies based on their function: the “orthodox” water transporting AQPs (AQP0, AQP1, AQP2, AQP4, AQP5, AQP6, and AQP8); and the aquaglycoporins (AQP3, AQP7, AQP9, and AQP10), which mediate the transport of water plus small uncharged solutes, such as glycerol, urea, and pyrimidines. Several AQP family members are expressed in human urothelium. The expression of AQP2 and AQP3 in rat ureter and bladder has been reported previously with AQP1 localized to endothelial cells. Both AQP2 and AQP3 are located primarily at the basolateral membrane of umbrella cells and the plasma membranes of the intermediate and basal cells.

In humans, transcripts for AQP3, AQP4, AQP7, AQP9, and AQP11 were detected in freshly isolated urothelia and normal human urothelial (NHU) cells in culture. Strong AQP3 expression was apparent at the cell borders in basal and intermediate cells in both urothelium in situ and in vitro differentiated cells. While expression of AQP3, AQP4, and AQP11 transcripts were consistent in bladder tissue and cultured urothelia, AQP9 was expressed in bladder tissue and differentiated NHU cultures, but not proliferative cultures. It has been suggested that the expression of AQP9 might be associated with terminal differentiation in transitional epithelia.

Studies also have indicated that the bladder epithelium may play a modulatory role in water and salt homeostasis. In dehydrated rats, a significant upregulation of AQP2 and AQP3 proteins was observed, providing plausible evidence that AQPs are involved in water and solute transport. Furthermore, urea transporters are expressed in the urothelium of bladder and ureters–. The urothelium also has pathways for ion reabsorption and aquaporin-independent water transport, although these pathways are unclear. Several studies have suggested that the urothelium can modify the composition of urine, depending on the hydration conditions, and/or bladder distension,.

Maintaining the barrier during mechanical changes

The bladder urothelium must withstand an astonishing array of punishment as it is exposed to tremendous mechanical stretch forces, osmotic pressure and hydrostatic pressure, all while needing to maintain one of the least permeable barriers in the body. Investigations into the effects of bladder filling and voiding on the structure and function of the umbrella cell TJ have shown that filling promotes a significant increase in the perimeter of the TJ ring, which is rapidly reversed back upon voiding. When rabbit urothelium mounted in an Ussing chamber is stretched, there is a significant drop in overall TEER and TJ-associated resistance, leading to umbrella cell TJs being leakier to ions. Remarkably, the integrity of the urothelial barrier is maintained even with a ten-fold drop in TEER, as no significant leakage of biotin, fluorescein, or ruthenium is detected across the urothelium under these conditions.

It is thought that maintaining barrier function upon stretching is enabled by a few specializations (Fig. 5). First, the umbrella cell transitions from a parasol shape to a squamous flat form during filling, transitioning from an apical diameter of ~30–50 μm in the relaxed state to ~50–150 μm when stretched. Second, bladder filling triggers a large pool of subapical DFVs to undergo RAB8a, RAB11a, and RAB27b-dependent exocytosis, leading to a dramatic increase of the apical surface area–,,–. The excess apical membrane is quickly internalized during voiding by an integrin-triggered, dynamin II (DNM2)-dependent, RhoA-dependent, and clathrin-independent, endocytic pathway,,,. The umbrella cell apical junctional ring also plays a critical role in maintaining the urothelial barrier while retaining the structure and function during bladder expansion and contraction. This property is not only limited to umbrella cells, as all epithelial cells are subjected to mechanical stimuli during development and normal physiological functions including lung inflation and fluid flow through nephrons or vasculature,,–.

In addition to these macroscopic changes, other tissue and cell shape changes accompany bladder filling alongside the above-mentioned remodelling of umbrella cells. As the bladder fills, the urothelium thins, and in species with multiple intermediate layers, the urothelium appears to have fewer cell layers. It is surmised, but not yet experimentally determined, that during filling, the intermediate cell layers slide past one another while maintaining their cell-cell contact. Finally, expansion modifies the distribution of proteins associated with the TJ,–, and affects junctional strand number and distribution–.

Urothelial sensory mechanisms

There is substantial evidence that the urothelium has specialized sensory and signaling properties enabling the urothelial cells to respond to several mechanical or chemical stimuli,. The urothelium responds to a variety of mechanical stresses during bladder filling and voiding by activating transducer proteins. During the changes in hydrostatic pressure that typically trigger micturition, the urothelial cells release transmitters such as ATP. The urothelium also responds to changes in urine osmolarity. Alterations in urine composition can be viewed as a form of stress, with urine contents varying in both in terms of their delivery rate and their composition.

The bladder urothelium expresses several different receptors and ion channels linked to mechanoceptive or nociceptive sensations,,–. These include purinergic (P2X1-7 and P2Y1, 2, 4),, adrenergic (α and β),, cholinergic (muscarinic; M1-5 and nicotinic α2-α10, β2 and β4),,, protease-activated receptors, acid sensing ion channels (ASIC), corticotrophin-releasing factor (CRF1, CRF2), neurotrophin receptors–, various transient receptor potential (TRP) channels (TRPV1, TRPV2, TRPV4, TRPM7, TRPM8, TRPA1),,–, and chemokine receptors such as CXCR4 and CX3CR1. The expression of these receptors and ion channels allows the urothelium to respond to diverse stimuli from a variety of sources. Sensory inputs include stretching and distension during bladder filling,,–, soluble factors found in urine such as nerve growth factor (NGF), acetylcholine,, ATP or norepinephrine released from nerves and inflammatory cells, chemokines (CXCL1, CXCL12, CX3CL1, CCL2), which are released from inflammatory cells,,, and changes in pH due to inflammation,. These diverse stimuli can lead to several outputs with complex results including the alteration in the flow of ions and other substances across the urothelium, changes in membrane turnover, and modification of the activity of underlying smooth muscle and neighboring sensory neurons.

Several signalling molecules are secreted by the urothelium, including neurotrophins, neuropeptides, ATP, acetylcholine, prostaglandins, nitric oxide, and cytokines,,,. These molecules can communicate with other cells such as bladder neurons, smooth muscle cells, interstitial cells, and inflammatory cells,. ATP has been demonstrated to act as a main messenger released from urothelial cells during purinergic mechanosensory transduction, which activates P2X3 receptors indicating bladder fullness, and pain,.

The bladder also expresses multiple TRP channels from different subfamilies. The TRP comprise a superfamily of nonspecific cationic ion channels that in the urinary bladder are highly expressed in, but not restricted to, primary afferent neurons; they are also expressed in the urothelium and some interstitial cells. Twenty eight TRP channels have been discovered so far in mammals consisting of seven subfamilies: TRPC (canonical), TRPM (melastatin), TRPV (vanilloid), TRPA (ankyrin), TRPP (polycystin), TRPML (mucolipin), and TRPN (no mechano-potential). TRP have specific tissue distributions, are activated by many exogenous and endogenous mediators,,, and may have functional roles in micturition,. A number of these channels are also associated with bladder disorders including overactive bladder (OAB) and interstitial cystitis/bladder pain syndrome (IC/BPS),.

TRPV1, the first subfamily to be identified, currently includes six members (TRPV1-6). The expression and function of TRPV1 in the urothelium,, TRPV2 in umbrella cells,, and TRPV4 in basal and intermediate cells,– are well-documented. The expression of TRPA1 and TRPM8 subfamilies has also been detected in the urothelium.

Mechanosensitive ion channels convert mechanical signals into electrochemical signals and are widely expressed in the urinary system. They are key mechanotransducers in response to stimuli such as shear stress, bladder distension, and emptying the bladder. Piezo1 and Piezo2 are the two family members of Piezo channels expressed in the urinary system. It has been shown that Piezo2 in the lower urinary tract has a dual role, acting as a sensor in both the bladder urothelium and innervating sensory neurons. It has been reported that humans and mice lacking functional Piezo2 have impaired bladder control while humans additionally exhibit deficient bladder-filling sensation. Furthermore, recent evidence also suggests that sensory dysfunction associated with UTI, such as urinary infrequency and pelvic pain, is due to sensitized bladder-innervating sensory afferents caused by the inflammatory events.

Diseases of the bladder

The bladder mucosa is constantly exposed to microorganisms because of its relative proximity to the gastrointestinal (GI) tract. In addition, in women, the urethral orifice is close to the vaginal mucosa with its own microbiota–. Urinary tract infections (UTIs) are the most common and frequent infections worldwide, infecting over 150 million people annually with high treatment costs–. UTIs can affect the upper (pyelonephritis) or lower (cystitis) urinary tract, with the latter being extremely common, affecting over half of women and 5% of men in their lifetimes. The most frequent bacterial cause of uncomplicated community-acquired UTI is uropathogenic E. coli (UPEC), representing over 80% of infections. These bacteria colonize the lower GI tract and can migrate across perineum to the urethra, gaining access to the urinary tract where they can cause disease. Other pathogens associated with uncomplicated UTI include Staphylococcus saprophyticus, Klebsiella species, Proteus mirabilis and Enterococcus faecalis, among many others, including some fungi.

The umbrella cells on the luminal side of the urothelium constitute the first barrier against invading uropathogens, forming a tight monolayer of highly differentiated and polarized cells. The impermeability of umbrella cells plus their protective glycan layer discourages the adherence of bacteria; additionally, the frequent unidirectional flow of urine helps to remove any adherent bacteria, making the urothelium one of the most challenging mucosal surfaces to colonize. There are other factors that can limit urothelial attachment such as changes in urine osmolarity, pH, soluble IgA, uromodulin (Tamm-Horsfall urinary glycoprotein), iron chelating siderophores and antimicrobial peptides (AMPs).

The urothelium expresses multiple toll-like receptors (TLRs) which recognize pathogen-associated molecular patterns (PAMPs)–, and damage-associated molecular patterns (DAMPs), generated upon cell or tissue damage. TLR activation triggers the production of inflammatory mediators such as cytokines and chemokines that help to clear infections. The common TLRs identified in the urinary tract include TLR2, TLR3, TLR4, TLR5, TLR9, and TLR11 (the latter in mice only). Studies have reported that urothelium from normal human bladders express TLR5 (weakly), TLR2, TLR3, and TLR7 (moderately), and TLR4 and TLR9 (strongly),.

UPEC infection is initiated by the attachment of E. coli to the urothelium via its lectin-type 1-fimbriae (FimH) adhesin, found at the tip of the Type I pilus, to urothelial surface receptor UPK1A, which is rich in mannose residues–. The reaction is FimH-specific and does not take place with any E. coli expressing other types of adhesins or lacking fimbria,. Upon invasion of the bladder urothelium, uropathogenic bacteria replicate, form intracellular bacterial communities (IBC), and invade neighboring cells. Mouse models show that once within the bladder urothelium, bacteria can survive for long periods leading to recurrent UTIs that are challenging to treat,,, although the situation in humans is less well understood.

Infection with UPEC initiates a host response that triggers umbrella cell death and exfoliation to promote bacterial removal,. But as this manoeuvre exposes the underlying cells to both toxic urine and existing uropathogens in the environment, the underlying cells rapidly proliferate to replace the shed cells within hours,. UPEC infection also activates TLR4, which is expressed at the apical surface of umbrella cells–, and its downstream effector myeloid differentiation factor 88 (MyD88) to facilitate bacterial clearance. In Tlr4-deficient mice challenged with UPEC, the infection persists in the bladder and the host exhibits an impaired IL-8 response and ineffective neutrophil mobilization. Pediatric patients with decreased granulocyte TLR4 expression are also more likely to have asymptomatic bacteriuria than those with normal TLR4 expression.

The activation of pattern recognition receptors (PRR) TLR4 and Nod-like receptor/Caspase 1 lead to the secretion of IL-6 and IL-1β which are detectable in urine,. The expression of cytokines along with other inflammatory mediators secreted by urothelial cells result in the influx of immune cells to the site of infection. Bladder urothelial cells secret several AMPs that complement the cytokine responses such as cathelicidin LL-37 and β-defensin; although this latter AMP is found in urine, it mainly originates from kidney epithelial cells. Both LL-37 and β-defensin also contribute to cytokine production and neutrophil recruitment in the bladder. Ribonuclease 7 is another AMP that has broad-spectrum microbial activity against many uropathogens. The soluble pattern recognition molecule pentraxin-related protein 3 (PTX3) is thought to lead to complement-mediated killing by binding to bacterial surfaces, and increasing bacteria uptake by phagocytes. In humans, increased UTI incidence is correlated with mutations in the PTX3 locus.

The urothelium not only forms a highly effective barrier to urine and pathogens, and functions as a source of soluble AMPs, but it also performs a critical role in regulating bladder volume in the course of urine filling and emptying. Unfortunately, this process can be hijacked by invading bacteria. The urothelium contains a large number of RAB27b+ DFVs. As mentioned previously, when the bladder fills, extra membrane is provided by DFVs, which spontaneously exocytose into the plasma membrane in a cyclic AMP (cAMP)-dependent manner. After the void, the intracellular DFVs form once again facilitate urothelial contraction by internalizing the RAB27+ membranes,. Following UPEC binding to the apical surface of the urothelium, TLR4 signalling leads to increased intracellular levels of cAMP, which consequently triggers spontaneous expulsion of RAB27b+ vesicles at the adherence site. Subsequently, the RAB27b+ vesicles retract from the cell surface and draw the invading bacteria back into the cells with them, encased in RAB27b+ vesicles,. The urothelium has a defense system capable of sensing the invading bacteria and initiates mechanisms to expel the intracellular bacteria. This activity is triggered by TLR4 localized in the vesicles encapsulating the bacteria and is initiated within a few minutes of bacterial entry.

Remarkably, not all intracellular bacteria are exocytosed from RAB27b+ vesicles and a considerable number of UPEC escape intracellular vesicles and enter the cytosol. A study showed that UPEC initiates escape by upregulating phospholipase PIdA upon sensing host immune responses. UPEC infection upregulates PIT1, a host phosphate transporter located on the vesicle membrane, via NF-κB, resulting in phosphate reduction which in return activates the expression of pldA to disrupt the vesicle membrane. A second exocytic pathway is activated by the cell autophagy system which recognizes and captures the bacteria in autophagosomes and transports them to the lysosome. It has been shown that mice hypomorphic for ATG16L1 have reduced UPEC persistence. Furthermore, network mapping of autophagy pathways has identified RAB33b, a Golgi-resident small GTPase, which interacts directly with ATG16L1 modulating autophagosome formation. Small RAB GTPases (RAB27b and RAB11a) are highly expressed in umbrella cells and are key for vesicle trafficking, UPK recycling and exosome-mediated intracellular UPEC expulsion. In addition, UPEC co-opts ferritinophagy (a selective form of autophagy) and shuttles into the autophagosomal and lysosomal compartments with ferritin-bound iron, facilitating UPEC survival and persistence within the urothelium. Autophagy usually leads to bacterial degradation, but UPEC can block acidification and survive within lysosomes. Studies using cultured human bladder cells have shown that the malfunctioning lysosomes containing UPEC are rapidly sensed by TRP mucolipin 3 (TRPML3), a cation channel expressed on the lysosomes. TRPML3 is activated when the pH within the lysosome increases, triggering the spontaneous exocytosis of these lysosomes. Contrary to the first wave of bacterial expulsion, bacteria expelled from lysosomes in this manner are encased within host membranes, preventing re-attachment of UPEC to the urothelium and ensuring bacterial removal in urine.

Another defense mechanism employed by the urothelium to reduce bacterial load is undergoing cell death and cell exfoliation into the urine, thus eliminating the cells that are associated with adherent and intracellular bacteria,. This allows the removal of large numbers of bacteria but consequently exposes the underlying cells to both toxic urine and existing uropathogens in the environment. It has also been demonstrated that the NF-E2-related factor 2 (NRF2) pathway is activated in response to UPEC-triggered reactive oxygen species (ROS) production. The NRF2 activation in urothelial cells causes the reduction of ROS production, inflammation, and cell death resulting in UPEC expulsion and a reduction in bacterial load.

Lower urinary tract symptoms

Lower urinary tract symptoms (LUTS), such as frequency, urgency, and dysuria, are particularly prevalent among adults. Patients with isolated or repeated episodes of LUTS with positive urine cultures are often treated with short courses of antibiotics. However, no aetiology is found for many LUTS patients with negative results using standard urine culture techniques, and no abnormal functional or anatomical urinary tract, although it should be noted that traditional tests have been shown to be insensitive and miss genuine infections. Patients with urgency as their main complaint and no signs of infection are often diagnosed with overactive bladder (OAB), while patients with pain, pressure, or discomfort are diagnosed with interstitial cystitis/bladder pain syndrome (IC/BPS).

IC/BPS is estimated to affect 3–8 million women and 1–4 million men. The difficulties in diagnosis originate not only from insensitive UTI tests, but also from many theories regarding pathophysiology and aetiology such as diminished GAG layer, altered permeability of the urothelium, uroinflammation, and neural upregulation. Studies have reported a decreased amount of GAG in the urine of patients with IC/BPS which has also been confirmed in animal models,. Another study examined tissue from bladder biopsies of patients with IC/PBS and observed considerable abnormalities in the level of CK18 (80% showing abnormalities), CK20 (87.5%) and uroplakins (56%). Studies of rodent models of IC/BPS also reported lower expression of urothelial surface proteins, their incorrect arrangements, and damage of TJs seen with electron microscopy. In patients with non-ulcerative IC/BPS, a more common IC/BPS accounting for almost 90% of all cases, a lower amount of UPK1A, UPK1B, and UPK2 mRNA expression were detected in bladder tissue apart from UPK3. UPK3-delta4, a splicing variant of UPK3, was significantly upregulated in IC samples, which has been suggested as a promising marker of IC/BPS. Further research is required to understand the etiology of OAB and IC/PBS, with the caveat that the development of more sensitive detection methods for UTI might well reveal an infective element for some unknown proportion of these cases.

Urothelial in vitro models to study host-pathogen interactions

Animal models provide an invaluable insight into disease pathogenesis. Although murine models of UTI remain indispensable, there are concerns that they do not always fully recapitulate the human tissue environment to correctly predict disease physiology or prospective treatments,. In such cases, the availability of suitable ex vivo or in vitro human urothelial culture models are beneficial to gather specific insights which could provide critical information.

Traditionally, two-dimensional (2D) monolayer cultures on flat or rigid surfaces have been used for cell-based studies and have proven to be a valuable method. However, their limitations have been increasingly recognized. As most cells in vivo are surrounded by extracellular matrix (ECM) and other cell types in a three-dimensional (3D) manner, 2D cultures do not sufficiently represent the normal 3D environment. As a result, 2D culture experiments sometimes result in misleading or unpredictive data for in vivo responses–. In contrast, recent studies have suggested that 3D cell culture systems, despite their obvious limitations such as lack of a blood supply or systemic responses, represent a more accurate, tissue-like microenvironment, and may be more reflective of in vivo cellular responses. Research has revealed that cells in a 3D culture environment differ morphologically and physiologically from cells in 2D cultures–. It is thought that the additional dimensionality of 3D cultures is the crucial attribute that leads to at least some key differences in cellular responses by conferring more reminiscence spatial and physical aspects of the culture–.

Human urothelial cultures are widely represented in vitro as immortalized or cancer-derived cell lines. However, normal immortalized cells are compromised in their ability to undergo cell differentiation and barrier formation, while the cancerous nature of established cell lines is also a drawback. Non-transformed NHU cells grown as monolayer cultures have been used extensively in many studies,. However, their rapid loss of quiescence and differentiation characteristics soon leads to a highly proliferative and non-specialized phenotype which governs their response–.

Arguably, the most biologically and structurally relevant in vitro model of the urothelium is provided by ex vivo cultures of the urothelium,, where the intact tissue retains most of its in situ tissue architecture. An alternative approach is explant culture, in which primary cultures are established from tissue fragments; however, the use of human organ or explant culture is largely hampered by the limited tissue supply. A “biomimetic” urothelial cell culture system propagated from normal human urothelial (NHU) cells have been described previously,, exhibiting barrier formation and a multilayer epithelium. The authors demonstrated morphological similarities between the developed “biomimetic” urothelial model and the naïve tissue.

The implications associated with the use of non-transformed normal urothelial cells such as ethics, finite lifespan, and donor variability can be hindrance for many studies. An alternative strategy to extend the lifespan of urothelial cells is immortalization by targeting the telomerase via overexpression of the catalytic subunit of human telomerase reverse transcriptase (hTERT),. This would maintain the in situ representation of primary cells combined with the in vitro immortality of cancer cell lines,. However, studies showed that hTERT-imortalization of human urothelial cells negatively impacts the differentiation or barrier forming capacity of the cells and thereby reducing their biological relevance,. On the other hand, our group has published a stratified, urine-tolerant biomimetic model derived from commercially available bladder progenitor cells which, despite being spontaneously transformed, still retain the ability to terminally differentiate. The most recent version, 3D urine-tolerant human urothelial (3D-UHU), has been improved to offer a homogenously differentiated umbrella cell layer, excellent barrier function and the ability to secrete key cytokines and chemokines in response to infection.

As an alternative approach, several studies have demonstrated that large number of viable normal urothelial cells can be generated from patient/donor urine samples,, or bladder washing,,. Nevertheless, caution is warranted as these cultures represent an epithelial cell population derived from various regions of the urinary tract and mainly from the kidneys,. Besides, it is unlikely that sufficient numbers of normal urothelial cells are voided in the urine, considering the longevity and low turnover of the urothelium. Nevertheless, one study did identify urine-derived stem cells that were a subpopulation of urine-derived stem cells with multipotent differentiation capacity,.

One way to harness the impressive self-renewal capacity of urothelial cells in vivo is to find the source of progenitor or stem cells that self-renew, regenerate, and differentiate in situ; however, as alluded to previously, the origin of urothelial stem cells is a subject of debate,,,,,,,. 3D organotypic cell cultures derived from primary tissues (either tissue subunits or single cells), adult stem cells, fetal/postnatal stem cells, pluripotent embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) offer possibilities of studying the urothelial cells in a more in vivo like condition. Adult stem cells are an attractive source for bioengineering a urothelium as they are relatively easy to obtain and culture and are autologous,,. Fetal or postnatal stem cells have also been differentiated into urothelium–.

However, both adult and fetal stem cells are limited by their poorly understood differentiation processes. Furthermore, adult stem cells have limited proliferation potential in vitro, and fetal cells have possible immunological consequences if being considered for regenerative medicine. Therefore, the pluripotent nature of ESCs and iPSCs make them attractive candidates. In a study using human PSC, cells were differentiated into bladder urothelial cells which expressed several marker genes such as uroplakin and cytokeratin; also, they formed a terminally differentiated monolayer. However the resulting cell layer stratification was not comparable to that of native urothelium. In another study, 3D bladder ‘assembloids’, organoids derived from normal urothelial stem cells or patients with bladder tumors, were reconstituted with stromal components. They manifested an organized structure with an epithelium surrounding stroma and an outer muscle layer. The assembloids exhibited mature adult bladder characteristics in cell composition and gene expression at the single-cell level; furthermore, they demonstrated regenerative responses to injury mimicking in vivo tissue dynamics. Apart from studies published by our group,,, most described models either were not exposed to urine or only for short periods–. This is potentially important as urine has an effect not only on human cell physiology, but also, in the case of UTI research, on bacterial behavior,.

In vitro modelling for bladder cancer-studies is a vibrant and expanding area but is beyond the scope of this review. These traditionally employ bladder carcinoma cells grade 1–4, but exciting inroads have also been made into personalized, patient-derived bladder cancer organoids.

Conclusions and future perspectives

The urothelium is a unique epithelial surface comprised of multiple cell layers. It can change size and shape to accommodate fluctuating volumes of urine and simultaneously provide a barrier to prevent absorption of toxic substances and to defend against microbial entry. Bladder dysfunction and urinary tract chronic diseases significantly impact quality of life for millions of people worldwide. Although much has been learned over the past decades, a number of unknowns remain to be elucidated, including how the urothelium differs with age; sex differences in basic biology and disease outcomes; integration of urothelial function with neuronal signaling; and urothelial-immune interactions. While rodent models have significantly improved our understanding of urinary tract disease pathogenesis, the considerable structural and biological differences between species calls for the development of alternative models. In the past few years, an immense effort has been dedicated to the development of a variety of human-based 3D culture systems as well as adoption of these models in drug discovery, cancer cell biology, stem cell biology, and in efforts to engineer functional tissues for implantation, among other cell-based research. Such 3D culture models provide suitable in vitro systems to study cellular responses in a setting that mimics the in vivo microenvironment,–. In addition, recent developments of organoids co-cultured with immune or rare cell types have significantly improved our understanding of the dynamic interactions between complex tissues and different cell types within a controlled environment.

Casting ahead to the future, we look forward to advances in human cell-based model technologies that overcome the biggest limitations of the current platforms, namely lack of a systemic environment to provide the necessary crosstalk. Once perfected, Microfluidic Organ Chip (Body-on-a-Chip) systems could allow communication between existing bladder microphysiological platforms alongside mechanical stimuli, vascular components, ECM, circulating immune cells and even resident microbial communities. There has already been one report of an unstratified human carcinoma cell line-derived urothelial model cultured adjacent to endothelial cells, which also contains flow and mechanical stretch components; combining this idea with a fully stratified non-cancer-derived urothelial model and further systemic elements would be the next logical step. Such fully integrated systems should be essential as complementary tools alongside both animal and clinical studies in patients to fully understand normal bladder physiology as well as how it can go wrong in infection, injury or disease.

References 351

  1. 1.

    Garcia MA, Nelson WJ, Chavez N. Cell – Cell Junctions Organize Structural. Cold Spring Harb. Perspect. Biol. 2017;10:1-28.

    Not in our library10.1101/cshperspect.a029181

  2. 2.

    Buckley A, Turner JR. Cell biology of tight junction barrier regulation and mucosal disease. Cold Spring Harb. Perspect. Biol. 2018;10:a029314.

    Not in our library10.1101/cshperspect.a029314

  3. 3.

    Shashikanth N, et al. Epithelial organization: the gut and beyond. Compr. Physiol. 2017;7:1497-1518.

    Not in our library10.1002/cphy.c170003

  4. 4.

    Winder M, Tobin G, Zupančič D, Romih R. Signalling molecules in the urothelium. Biomed. Res. Int. 2014;2014:297295.

    Not in our library10.1155/2014/297295

  5. 5.

    Hicks RM. The mammalian urinary bladder: an accommodating organ. Biol. Rev. Camb. Philos. Soc. 1975;50:215-246.

    Not in our library10.1111/j.1469-185x.1975.tb01057.x

  6. 6.

    Yu W, Hill WG. Defining protein expression in the urothelium: a problem of more than transitional interest. Am. J. Physiol. - Ren. Physiol. 2011;301:932-942.

    Not in our library10.1152/ajprenal.00334.2011

  7. 7.

    Song J, Abraham SN. TLR-mediated immune responses in the urinary tract. Curr. Opin. Microbiol. 2008;11:66-73.

    Not in our library10.1016/j.mib.2007.12.001

  8. 8.

    Jaimes-Parra BD, et al. Ex vivo construction of a novel model of bioengineered bladder mucosa: a preliminary study. Int. J. Urol. 2016;23:85-92.

    Not in our library10.1111/iju.12963

  9. 9.

    Osborn SL, Kurzrock EA. Production of Urothelium from Pluripotent Stem Cells for Regenerative Applications. Curr. Urol. Rep. 2015;16:1-7.

    Not in our library10.1007/s11934-014-0466-6

  10. 10.

    Balsara ZR, Li X. Sleeping beauty: awakening urothelium from its slumber. Am. J. Physiol. - Ren. Physiol. 2017;312:F732-F743.

    Not in our library10.1152/ajprenal.00337.2016

  11. 11.

    Jones JCR. Hemidesmosomes in Bladder Epithelial. Cells. 2001;57:2001.

    Not in our library10.1016/s0090-4295(01)01025-1

  12. 12.

    Owaribe K, et al. The hemidesmosomal plaque: I. Characterization of a major constituent protein as a differentiation marker for certain forms of epithelia. Differentiation. 1990;45:207-220.

    Not in our library10.1111/j.1432-0436.1990.tb00475.x

  13. 13.

    Borradori L, Sonnenberg A. Structure and function of hemidesmosomes: More than simple adhesion complexes. J. Investig. Dermatol. 1999;112:411-418.

    Not in our library10.1046/j.1523-1747.1999.00546.x

  14. 14.

    Li Y, et al. Single-cell transcriptomes of mouse bladder urothelium uncover novel cell type markers and urothelial differentiation characteristics. Cell Prolif. 2021;54:1-17.

    Not in our library10.1111/cpr.13007

  15. 15.

    Yamany T, Batavia JVan, Mendelsohn C, Batavia JVan, Mendelsohn C. Formation and regeneration of the urothelium. Curr. Opin. Organ Transplant. 2014;19:323-330.

    Not in our library10.1097/mot.0000000000000084

  16. 16.

    Gandhi D, et al. Retinoid signaling in progenitors controls specification and regeneration of the urothelium. Dev. Cell. 2013;26:469-482.

    Not in our library10.1016/j.devcel.2013.07.017

  17. 17.

    Shin K, et al. Hedgehog/Wnt feedback supports regenerative proliferation of epithelial stem cells in bladder. Nature. 2011;472:110-116.

    Not in our library10.1038/nature09851

  18. 18.

    Romih R, Jezernik K, Mašera A. Uroplankins and cytokeratins in the regenerating rat urothelium after sodium saccharin treatment. Histochem. Cell Biol. 1998;109:263-269.

    Not in our library10.1007/s004180050226

  19. 19.

    Wu XR, Kong XP, Pellicer A, Kreibich G, Sun TT. Uroplakins in urothelial biology, function, and disease. Kidney Int. 2009;75:1153-1165.

    Not in our library10.1038/ki.2009.73

  20. 20.

    Jost SP, Goslingt JA, Dixon JS. The morphology of normal human bladder urothelium. J. Anat. 1989;167:103-115.

    Not in our library

  21. 21.

    Wu XR, et al. Mammalian uroplakins. A group of highly conserved urothelial differentiation-related membrane proteins. J. Biol. Chem. 1994;269:13716-13724.

    Not in our library10.1016/s0021-9258(17)36889-8

  22. 22.

    Khandelwal P, Abraham SN, Apodaca G. Cell biology and physiology of the uroepithelium. Am. J. Physiol. - Ren. Physiol. 2009;297:F1477-F1501.

    Not in our library10.1152/ajprenal.00327.2009

  23. 23.

    Dalghi MG, Montalbetti N, Carattino MD, Apodaca G. The urothelium: life in a liquid environment. Physiol. Rev. 2020;100:1621-1705.

    Not in our library10.1152/physrev.00041.2019

  24. 24.

    Apodaca G. The uroepithelium: Not just a passive barrier. Traffic. 2004;5:117-128.

    Not in our library10.1046/j.1600-0854.2003.00156.x

  25. 25.

    Kullmann FA, et al. Urothelial proliferation and regeneration after spinal cord injury. Am. J. Physiol. - Ren. Physiol. 2017;313:F85-F102.

    Not in our library10.1152/ajprenal.00592.2016

  26. 26.

    Acharya P, et al. Distribution of the tight junction proteins ZO-1, occludin, and claudin-4, -8, and -12 in bladder epithelium. Am. J. Physiol. - Ren. Physiol. 2004;287:F305-F318.

    Not in our library10.1152/ajprenal.00341.2003

  27. 27.

    Smith NJ, et al. The human urothelial tight junction: claudin 3 and the ZO-1α+ switch. Bladder. 2015;2:9.

    Not in our library10.14440/bladder.2015.33

  28. 28.

    Jackson AR, Ching CB, McHugh KM, Becknell B. Roles for urothelium in normal and aberrant urinary tract development. Nat. Rev. Urol. 2020;17:459-468.

    Not in our library10.1038/s41585-020-0348-2

  29. 29.

    Liang FX, et al. Organization of uroplakin subunits: transmembrane topology, pair formation and plaque composition. Biochem. J. 2001;355:13-18.

    Not in our library10.1042/bj3550013

  30. 30.

    Lavelle J, et al. Bladder permeability barrier: recovery from selective injury of surface epithelial cells. Am. J. Physiol. - Ren. Physiol. 2002;283:242-253.

    Not in our library10.1152/ajprenal.00307.2001

  31. 31.

    Hu P, et al. Role of membrane proteins in permeability barrier function: uroplakin ablation elevates urothelial permeability. Am. J. Physiol. - Ren. Physiol. 2002;283:1200-1207.

    Not in our library10.1152/ajprenal.00043.2002

  32. 32.

    Khandelwal P, et al. Rab11a-dependent exocytosis of discoidal/fusiform vesicles in bladder umbrella cells. Proc. Natl Acad. Sci. USA. 2008;105:15773-15778.

    Not in our library10.1073/pnas.0805636105

  33. 33.

    Weiqun Y, Khandelwal P, A G. Distinct Apical and Basolateral Membrane Requirements for Stretch-induced Membrane Traffic at the Apical Surface of Bladder Umbrella Cells. Mol. Biol. Cell. 2009;20:2673-2683.

    Not in our library10.1091/mbc.e08-04-0439

  34. 34.

    Truschel ST, et al. Stretch-regulated exocytosis/endocytosis in bladder umbrella cells. Mol. Biol. Cell. 2002;13:830-846.

    Not in our library10.1091/mbc.01-09-0435

  35. 35.

    Zhou G, et al. MAL facilitates the incorporation of exocytic uroplakin-delivering vesicles into the apical membrane of urothelial umbrella cells. Mol. Biol. Cell. 2012;23:1354-1366.

    Not in our library10.1091/mbc.e11-09-0823

  36. 36.

    Khandelwal P, et al. A Rab11a-Rab8a-Myo5B network promotes stretch-regulated exocytosis in bladder umbrella cells. Mol. Biol. Cell. 2013;24:1007-1019.

    Not in our library10.1091/mbc.e12-08-0568

  37. 37.

    Veranič P, Jezernik K. Trajectorial organisation of cytokeratins within the subapical region of umbrella cells. Cell Motil. Cytoskeleton. 2002;53:317-325.

    Not in our library10.1002/cm.10077

  38. 38.

    Habuka M, et al. The urinary bladder transcriptome and proteome defined by transcriptomics and antibody-based profiling. PLoS ONE. 2015;10:1-13.

    Not in our library10.1371/journal.pone.0145301

  39. 39.

    Georgas KM, et al. An illustrated anatomical ontology of the developing mouse lower urogenital tract. Dev. 2015;142:1893-1908.

    Not in our library10.1242/dev.117903

  40. 40.

    Mysorekar IU, Isaacson-Schmid M, Walker JN, Mills JC, Hultgren SJ. Bone Morphogenetic Protein 4 Signaling Regulates Epithelial Renewal in the Urinary Tract in Response to Uropathogenic Infection. Cell Host Microbe. 2009;5:463-475.

    Not in our library10.1016/j.chom.2009.04.005

  41. 41.

    Tash JA, David SG, Vaughan ED, Herzlinger DA. Fibroblast growth factor-7 regulates stratification of the bladder urothelium. J. Urol. 2001;166:2536-2541.

    Not in our library10.1016/s0022-5347(05)65630-3

  42. 42.

    Liaw A, et al. Development of the human bladder and ureterovesical junction. Differentiation. 2018;103:66-73.

    Not in our library10.1016/j.diff.2018.08.004

  43. 43.

    Jost SP, Potten CS. Urothelial Proliferation In Growing Mice. Cell Prolif. 1986;19:155-160.

    Not in our library10.1111/j.1365-2184.1986.tb00725.x

  44. 44.

    Jost SP. Cell cycle of normal bladder urothelium in developing and adult mice. Virchows Arch. B Cell Pathol. Incl. Mol. Pathol. 1989;57:27-36.

    Not in our library10.1007/bf02899062

  45. 45.

    Mulvey MA, et al. Induction and evasion of host defenses by type 1-piliated uropathogenic Escherichia coli. Sci. (80-.). 1998;282:1494-1497.

    Not in our library10.1126/science.282.5393.1494

  46. 46.

    Romih R, Koprivec D, Martincic DS, Jezernik K. Restoration of the rat urothelium after cyclophosphamide treatment. Cell Biol. Int. 2001;25:531-537.

    Not in our library10.1006/cbir.2000.0658

  47. 47.

    Mysorekar IU, Hultgren SJ. Mechanisms of uropathogenic Escherichia coli persistence and eradication from the urinary tract. Proc. Natl Acad. Sci. 2006;103:14170-14175.

    Not in our library10.1073/pnas.0602136103

  48. 48.

    Colopy SA, Bjorling DE, Mulligan WA, Bushman W. A population of progenitor cells in the basal and intermediate layers of the murine bladder urothelium contributes to urothelial development and regeneration. Dev. Dyn. 2014;243:988-998.

    Not in our library10.1002/dvdy.24143

  49. 49.
  50. 50.

    Mysorekar IU, Mulvey MA, Hultgren SJ, Gordon JI. Molecular regulation of urothelial renewal and host defenses during infection with uropathogenic Escherichia coli. J. Biol. Chem. 2002;277:7412-7419.

    Not in our library10.1074/jbc.m110560200

  51. 51.

    Böck M, et al. Identification of ELF3 as an early transcriptional regulator of human urothelium. Dev. Biol. 2014;386:321-330.

    Not in our library10.1016/j.ydbio.2013.12.028

  52. 52.

    Boer WIDe, Schuller AGP, Vermey M, Kwast TH. Van Der Expression of growth factors and receptors during specific phases in regenerating urothelium after acute injury in vivo. Am. J. Pathol. 1994;145:1199-1207.

    Not in our library

  53. 53.

    Ling S, et al. An EGFR-ERK-SOX9 signaling cascade links urothelial development and regeneration to cancer. Cancer Res. 2011;71:3812-3821.

    Not in our library10.1158/0008-5472.can-10-3072

  54. 54.

    Pignon JC, et al. P63-expressing cells are the stem cells of developing prostate, bladder, and colorectal epithelia. Proc. Natl Acad. Sci. USA. 2013;110:8105-8110.

    Not in our library10.1073/pnas.1221216110

  55. 55.

    Flores-Mireles AL, Walker JN, Caparon M, Hultgren SJ. Urinary tract infections: epidemiology, mechanisms of infection and treatment options. Nat. Rev. Microbiol. 2015;13:269-284.

    Not in our library10.1038/nrmicro3432

  56. 56.

    Caparon KWDKAKMG, Hultgren SJ. A tale of two pili: assembly and function of pili in bacteria. Gerontology. 2015;61:515-525.

    Not in our library

  57. 57.

    Min G, et al. Localization of uroplakin Ia, the urothelial receptor for bacterial adhesin FimH, on the six inner domains of the 16 nm urothelial plaque particle. J. Mol. Biol. 2002;317:697-706.

    Not in our library10.1006/jmbi.2002.5442

  58. 58.

    Wang, C., Ross, W.T. & Mysorekar, I.U. Urothelial Generation and Regeneration in Development, Injury, and Cancer. Spring644, 1–14 (2009).

    Not in our library10.1002/dvdy.24487

  59. 59.

    Bohnenpoll T, et al. Diversification of cell lineages in ureter development. J. Am. Soc. Nephrol. 2017;28:1792-1801.

    Not in our library10.1681/asn.2016080849

  60. 60.

    Jackson AR, et al. Krt5+ urothelial cells are developmental and tissue repair progenitors in the kidney. Am. J. Physiol. - Ren. Physiol. 2019;317:F757-F766.

    Not in our library10.1152/ajprenal.00171.2019

  61. 61.

    Wiessner GB, Plumber SA, Xiang T, Mendelsohn CL. Development, regeneration and tumorigenesis of the urothelium. Development. 2022;149:dev198184.

    Not in our library10.1242/dev.198184

  62. 62.

    Schäfer FM, et al. Mode of Surgical Injury Influences the Source of Urothelial Progenitors during Bladder Defect Repair. Stem Cell Rep. 2017;9:2005-2017.

    Not in our library10.1016/j.stemcr.2017.10.025

  63. 63.

    Wu XR, Manabe M, Yu J, Sun TT. Large scale purification and immunolocalization of bovine uroplakins I, II, and III. Molecular markers of urothelial differentiation. J. Biol. Chem. 1990;265:19170-19179.

    Not in our library10.1016/s0021-9258(17)30640-3

  64. 64.

    Wu XR, Medina JJ, Sun TT. Selective interactions of UPIa and UPIb, two members of the transmembrane 4 superfamily, with distinct single transmembrane-domained proteins in differentiated urothelial cells. J. Biol. Chem. 1995;270:29752-29759.

    Not in our library10.1074/jbc.270.50.29752

  65. 65.

    Deng FM, et al. Uroplakin IIIb, a urothelial differentiation marker, dimerizes with uroplakin Ib as an early step of urothelial plaque assembly. J. Cell Biol. 2002;159:685-694.

    Not in our library10.1083/jcb.200204102

  66. 66.

    Yu J, Lin JH, Wu XR, Sun TT. Uroplakins Ia and Ib, two major differentiation products of bladder epithelium, belong to a family of four transmembrane domain (4TM) proteins. J. Cell Biol. 1994;125:171-182.

    Not in our library10.1083/jcb.125.1.171

  67. 67.

    Hu C-CA, et al. Assembly of Urothelial Plaques: Tetraspanin Function in Membrane Protein Traffickin. Mol. Biol. Cell. 2005;16:5356-5372.

    Not in our library10.1091/mbc.e05-02-0136

  68. 68.

    Min G, Wang H, Sun TT, Kong XP. Structural basis for tetraspanin functions as revealed by the cryo-EM structure of uroplakin complexes at 6-Å resolution. J. Cell Biol. 2006;173:975-983.

    Not in our library10.1083/jcb.200602086

  69. 69.

    Tu T-TSL, Kreibich G. Specific Heterodimer Formation Is a Prerequisite for Uroplakins to Exit from the Endoplasmic Reticulum. Mol. Biol. Cell. 2002;13:1977-2000.

    Not in our library10.1091/mbc.e02-04-0211

  70. 70.

    Kachar B, et al. Three-dimensional analysis of the 16 nm urothelial plaque particle: Luminal surface exposure, preferential head-to-head interaction, and hinge formation. J. Mol. Biol. 1999;285:595-608.

    Not in our library10.1006/jmbi.1998.2304

  71. 71.

    Sun TT, Zhao H, Provet J, Aebi U, Wu XR. Formation of asymmetric unit membrane during urothelial differentiation. Mol. Biol. Rep. 1996;23:3-11.

    Not in our library10.1007/bf00357068

  72. 72.

    Hu P, et al. Ablation of uroplakin III gene results in small urothelial plaques, urothelial leakage, and vesicoureteral reflux. Urology. 2001;57:117.

    Not in our library10.1016/s0090-4295(01)01062-7

  73. 73.
  74. 74.

    Mo L, Cheng J, Lee EYHPHP, Sun TT, Wu XR. Gene deletion in urothelium by specific expression of Cre recombinase. Am. J. Physiol. - Ren. Physiol. 2005;289:562-568.

    Not in our library10.1152/ajprenal.00368.2004

  75. 75.

    Munipalli SB, Yenugu S, Babu Munipalli S, Yenugu S. Uroplakin expression in the male reproductive tract of rat. Gen. Comp. Endocrinol. 2019;281:153-163.

    Not in our library10.1016/j.ygcen.2019.06.003

  76. 76.
  77. 77.

    Kanamori-Katayama M, et al. LRRN4 and UPK3B are markers of primary mesothelial cells. PLoS ONE. 2011;6:2-9.

    Not in our library10.1371/journal.pone.0025391

  78. 78.

    Liao Y, et al. Uroplakins play conserved roles in egg fertilization and acquired additional urothelial functions during mammalian divergence. Mol. Biol. Cell. 2018;29:3128-3143.

    Not in our library10.1091/mbc.e18-08-0496

  79. 79.

    Coulombe PA, Bousquet O, Ma L, Yamada S, Wirtz D. The ‘ins’ and ‘outs’ of intermediate filament organization. Trends Cell Biol. 2000;10:420-428.

    Not in our library10.1016/s0962-8924(00)01828-6

  80. 80.

    Galou M, et al. The importance of intermediate filaments in the adaptation of tissues to mechanical stress: evidence from gene knockout studies. Biol. Cell. 1997;89:85-97.

    Not in our library10.1111/j.1768-322x.1997.tb00997.x

  81. 81.

    Veranic P, Jezernik K. The Cytokeratins of Urinary Bladder Epithelial Cells. Asian J. Cell Biol. 2005;1:1-8.

    Not in our library10.3923/ajcb.2006.1.8

  82. 82.

    Coulombe PA, Omary MB. ‘Hard’ and ‘soft’ principles defining the structure, function and regulation of keratin intermediate filaments. Curr. Opin. Cell Biol. 2002;14:110-122.

    Not in our library10.1016/s0955-0674(01)00301-5

  83. 83.

    Moll R, Franke WW, Schiller DL, Geiger B, Krepler R. The catalog of human cytokeratins: patterns of expression in normal epithelia, tumors and cultured cells. Cell. 1982;31:11-24.

    Not in our library10.1016/0092-8674(82)90400-7

  84. 84.

    Alonso A, Ikinger U, Kartenbeck J. Staining patterns of keratins in the human urinary tract. Histol. Histopathol. 2009;24:1425-1437.

    Not in our library10.14670/hh-24.1425

  85. 85.

    Erman A, Veranič P, Pšeničnik M, Jezernik K. Superficial cell differentiation during embryonic and postnatal development of mouse urothelium. Tissue Cell. 2006;38:293-301.

    Not in our library10.1016/j.tice.2006.07.001

  86. 86.

    Liang FX, et al. Cellular basis of urothelial squamous metaplasia: roles of lineage heterogeneity and cell replacement. J. Cell Biol. 2005;171:835-844.

    Not in our library10.1083/jcb.200505035

  87. 87.

    Riedel I, et al. Urothelial umbrella cells of human ureter are heterogeneous with respect to their uroplakin composition: Different degrees of urothelial maturity in ureter and bladder? Eur. J. Cell Biol. 2005;84:393-405.

    Not in our library10.1016/j.ejcb.2004.12.011

  88. 88.

    Troyanovsky SM, Guelstein VI, Tchipysheva TA, Krutovskikh VA, Bannikov GA. Patterns of expression of keratin 17 in human epithelia: Dependency on cell position. J. Cell Sci. 1989;93:419-426.

    Not in our library10.1242/jcs.93.3.419

  89. 89.

    Harnden P, Eardley I, Joyce AD, Southgate J. Cytokeratin 20 as an objective marker of urothelial dysplasia. Br. J. Urol. 1996;78:870-875.

    Not in our library10.1046/j.1464-410x.1996.23511.x

  90. 90.

    Sandilands A, et al. Generation and Characterisation of Keratin 7 (K7) Knockout Mice. PLoS ONE. 2013;8:1-11.

    Not in our library10.1371/journal.pone.0064404

  91. 91.

    Lin C, et al. Constitutive β-catenin activation induces male-specific tumorigenesis in the bladder urothelium. Cancer Res. 2013;73:5914-5925.

    Not in our library10.1158/0008-5472.can-12-4198

  92. 92.

    Smith FJDD, et al. Cloning of human, murine, and marsupial keratin 7 and a survey of K7 expression in the mouse. Biochem. Biophys. Res. Commun. 2002;297:818-827.

    Not in our library10.1016/s0006-291x(02)02288-x

  93. 93.

    Moll R, et al. Cytokeratins in normal and malignant transitional epithelium. Maintenance of expression of urothelial differentiation features in transitional cell carcinomas and bladder carcinoma cell culture lines. Am. J. Pathol. 1988;132:123-144.

    Not in our library

  94. 94.

    Achtstatter T, Moll R, Moore B, Franke WW. Cytokeratin polypeptide patterns of different epithelia of the human male urogenital tract: Immunofluorescence and gel electrophoretic studies. J. Histochem. Cytochem. 1985;33:415-426.

    Not in our library10.1177/33.5.2580881

  95. 95.

    Fishwick C, et al. Heterarchy of transcription factors driving basal and luminal cell phenotypes in human urothelium. Cell Death Differ. 2017;24:809-818.

    Not in our library10.1038/cdd.2017.10

  96. 96.

    Varley CL, Southgate J. Effects of PPAR agonists on proliferation and differentiation in human urothelium. Exp. Toxicol. Pathol. 2008;60:435-441.

    Not in our library10.1016/j.etp.2008.04.009

  97. 97.

    Varley CL, Stahlschmidt J, Smith B, Stower M, Southgate J. Activation of Peroxisome Proliferator-Activated Receptor-γ Reverses Squamous Metaplasia and Induces Transitional Differentiation in Normal Human Urothelial Cells. Am. J. Pathol. 2004;164:1789-1798.

    Not in our library10.1016/s0002-9440(10)63737-6

  98. 98.

    Klingler CH. Glycosaminoglycans: how much do we know about their role in the bladder? Urologia. 2016;83:11-14.

    Not in our library10.5301/uro.5000184

  99. 99.

    Chang A, Hammond TG, Sun TT, Zeidel ML. Permeability properties of the mammalian bladder apical membrane. Am. J. Physiol. - Cell Physiol. 1994;267:483-492.

    Not in our library10.1152/ajpcell.1994.267.5.c1483

  100. 100.

    Levin S, Richter WR. Ultrastructure of cell surface coat (glycocalyx) in rat urinary bladder epithelium. Cell Tissue Res. 1975;158:281-283.

    Not in our library10.1007/bf00219966

  101. 101.

    Monis B, Dorfman HD. Some histochemical observations on transitional epithelium of man. J. Histochem. Cytochem. 1967;15:475-481.

    Not in our library10.1177/15.8.475

  102. 102.

    Damiano R, Cicione A. The role of sodium hyaluronate and sodium chondroitin sulphate in the management of bladder disease. Ther. Adv. Urol. 2011;3:223-232.

    Not in our library10.1177/1756287211418723

  103. 103.

    Parsons CL, Greenspan C, Moore SW, Mulholland SG. Role of surface mucin in primary antibacterial defense of bladder. Urology. 1977;9:48-52.

    Not in our library10.1016/0090-4295(77)90284-9

  104. 104.

    Farquhar MG, Palade GE. Junctional complexes in various epithelia. J. Cell Biol. 1963;17:375-412.

    Not in our library10.1083/jcb.17.2.375

  105. 105.

    Franke WW. Discovering the molecular components of intercellular junctions-a historical view. Cold Spring Harb. Perspect. Biol. 2009;1:1-34.

    Not in our library10.1101/cshperspect.a003061

  106. 106.

    Pinheiro D, Bellaïche Y. Mechanical Force-Driven Adherens Junction Remodeling and Epithelial Dynamics. Dev. Cell. 2018;47:3-19.

    Not in our library10.1016/j.devcel.2018.09.014

  107. 107.

    Rübsam M, et al. Adherens junctions and desmosomes coordinate mechanics and signaling to orchestrate tissue morphogenesis and function: an evolutionary perspective. Cold Spring Harb. Perspect. Biol. 2018;10:a029207.

    Not in our library10.1101/cshperspect.a029207

  108. 108.

    Zihni C, Mills C, Matter K, Balda MS. Tight junctions: from simple barriers to multifunctional molecular gates. Nat. Rev. Mol. Cell Biol. 2016;17:564-580.

    Not in our library10.1038/nrm.2016.80

  109. 109.

    Lewis SA. Everything you wanted to know about the bladder epithelium but were afraid to ask. Environ. Pollut. 2005;138:377.

    Not in our library10.1152/ajprenal.2000.278.6.f867

  110. 110.

    Lewis SA, Diamond JM. Na+ transport by rabbit urinary bladder, a tight epithelium. J. Membr. Biol. 1976;28:1-40.

    Not in our library10.1007/bf01869689

  111. 111.

    Lewis SA, Eaton DC, Diamond JM. The mechanism of Na+ transport by rabbit urinary bladder. J. Membr. Biol. 1976;28:41-70.

    Not in our library10.1007/bf01869690

  112. 112.

    Claude P. Morphological factors influencing transepithelial permeability: a model for the resistance of the Zonula Occludens. J. Membr. Biol. 1978;39:219-232.

    Not in our library10.1007/bf01870332

  113. 113.

    Easter DW, Wade JB, Boyer JL. Structural integrity of hepatocyte tight junctions. J. Cell Biol. 1983;96:745-749.

    Not in our library10.1083/jcb.96.3.745

  114. 114.

    Madara JL, Dharmsathaphorn K. Occluding junction structure-function relationships in a cultured epithelial monolayer. J. Cell Biol. 1985;101:2124-2733.

    Not in our library10.1083/jcb.101.6.2124

  115. 115.

    Madara JL, Pappenheimer JR. Structural basis for physiological regulation of paracellular pathways in intestinal epithelia. J. Membr. Biol. 1987;100:149-164.

    Not in our library10.1007/bf02209147

  116. 116.

    Schneeberger EE, McCormack JM. Intercellular junctions in upper airway submucosal glands of the rat: a tracer and freeze fracture study. Anat. Rec. 1984;210:421-433.

    Not in our library10.1002/ar.1092100303

  117. 117.

    Itallie CMVan, Anderson JM. Architecture of tight junctions and principles of molecular composition. Semin. Cell Dev. Biol. 2014;36:157-165.

    Not in our library10.1016/j.semcdb.2014.08.011

  118. 118.

    Gonzalez-Mariscal L, Chávez de Ramírez B, Cereijido M. Tight junction formation in cultured epithelial cells (MDCK). J. Membr. Biol. 1985;86:113-125.

    Not in our library10.1007/bf01870778

  119. 119.

    Furuse M, Sasaki H, Fujimoto K, Tsukita S. A single gene product, claudin-1 or -2, reconstitutes tight junction strands and recruits occludin in fibroblasts. J. Cell Biol. 1998;143:391-401.

    Not in our library10.1083/jcb.143.2.391

  120. 120.

    Furuse M, Furuse K, Sasaki H, Tsukita S. Conversion of zonulae occludentes from tight to leaky strand type by introducing claudin-2 into Madin-Darby canine kidney I cells. J. Cell Biol. 2001;153:263-272.

    Not in our library10.1083/jcb.153.2.263

  121. 121.

    Itallie CMVan, Anderson JM. Claudins and epithelial paracellular transport. Annu. Rev. Physiol. 2006;68:403-429.

    Not in our library10.1146/annurev.physiol.68.040104.131404

  122. 122.

    Anderson JM, Van Itallie CM. Physiology and function of the tight junction. Ital. J. Gastroenterol. Hepatol. 1999;31:481-488.

    Not in our library

  123. 123.

    Varley CL, et al. PPARγ-regulated tight junction development during human urothelial cytodifferentiation. J. Cell. Physiol. 2006;208:407-417.

    Not in our library10.1002/jcp.20676

  124. 124.

    Saitou M, et al. Occludin-deficient embryonic stem cells can differentiate into polarized epithelial cells bearing tight junctions. J. Cell Biol. 1998;141:397-408.

    Not in our library10.1083/jcb.141.2.397

  125. 125.

    Inai T, Kobayashi J, Shibata Y. Claudin-1 contributes to the epithelial barrier function in MDCK cells. Eur. J. Cell Biol. 1999;78:849-855.

    Not in our library10.1016/s0171-9335(99)80086-7

  126. 126.

    McCarthy KM, et al. Inducible expression of claudin-1-myc but not occludin-VSV-G results in aberrant tight junction strand formation in MDCK cells. J. Cell Sci. 2000;113:3387-3398.

    Not in our library10.1242/jcs.113.19.3387

  127. 127.

    Freire VS, et al. MicroRNAs may mediate the down-regulation of neurokinin-1 receptor in chronic bladder pain syndrome. Am. J. Pathol. 2010;176:288-303.

    Not in our library10.2353/ajpath.2010.090552

  128. 128.

    Sánchez Freire V, Burkhard FC, Schmitz A, Kessler TM, Monastyrskaya K. Structural differences between the bladder dome and trigone revealed by mRNA expression analysis of cold-cut biopsies. BJU Int. 2011;108:E126-E135.

    Not in our library10.1111/j.1464-410x.2010.09934.x

  129. 129.

    Boireau S, et al. DNA-methylation-dependent alterations of claudin-4 expression in human bladder carcinoma. Carcinogenesis. 2007;28:246-258.

    Not in our library10.1093/carcin/bgl120

  130. 130.

    Nakanishi K, et al. Expression of occludin and claudins 1, 3, 4, and 7 in urothelial carcinoma of the upper urinary tract. Am. J. Clin. Pathol. 2008;130:43-49.

    Not in our library10.1309/u77a6btexvca5d0e

  131. 131.

    Székely E, et al. Expression of claudins and their prognostic significance in noninvasive urothelial neoplasms of the human urinary bladder. J. Histochem. Cytochem. 2011;59:932-941.

    Not in our library10.1369/0022155411418829

  132. 132.

    Amasheh S, et al. Claudin-2 expression induces cation-selective channels in tight junctions of epithelial cells. J. Cell Sci. 2002;115:4969-4976.

    Not in our library10.1242/jcs.00165

  133. 133.

    Hou J, Gomes AS, Paul DL, Goodenough DA. Study of claudin function by RNA interference. J. Biol. Chem. 2006;281:36117-36123.

    Not in our library10.1074/jbc.m608853200

  134. 134.

    Itallie CM, et al. The density of small tight junction pores varies among cell types and is increased by expression of claudin-2. J. Cell Sci. 2008;121:298-305.

    Not in our library10.1242/jcs.021485

  135. 135.

    Enck AH, Berger UV, Yu ASL. Claudin-2 is selectively expressed in proximal nephron in mouse kidney. Am. J. Physiol. - Ren. Physiol. 2001;281:966-974.

    Not in our library10.1152/ajprenal.2001.281.5.f966

  136. 136.

    Holmes JL, Itallie CMVan, Rasmussen JE, Anderson JM. Claudin profiling in the mouse during postnatal intestinal development and along the gastrointestinal tract reveals complex expression patterns. Gene Expr. Patterns. 2006;6:581-588.

    Not in our library10.1016/j.modgep.2005.12.001

  137. 137.

    Muto S, et al. Claudin-2-deficient mice are defective in the leaky and cation-selective paracellular permeability properties of renal proximal tubules. Proc. Natl Acad. Sci. USA. 2010;107:8011-8016.

    Not in our library10.1073/pnas.0912901107

  138. 138.

    Milatz S, et al. Claudin-3 acts as a sealing component of the tight junction for ions of either charge and uncharged solutes. Biochim. Biophys. Acta - Biomembr. 2010;1798:2048-2057.

    Not in our library10.1016/j.bbamem.2010.07.014

  139. 139.

    Törzsök P, et al. Claudins and Ki-67: Potential Markers to Differentiate Low- and High-Grade Transitional Cell Carcinomas of the Urinary Bladder. J. Histochem. Cytochem. 2011;59:1022-1030.

    Not in our library10.1369/0022155411424606

  140. 140.
  141. 141.

    Bürgel N, et al. Mechanisms of diarrhea in collagenous colitis. Gastroenterology. 2002;123:433-443.

    Not in our library10.1053/gast.2002.34784

  142. 142.

    Lejeune M, Moreau F, Chadee K. Prostaglandin E2 produced by entamoeba histolytica signals via EP4 receptor and alters claudin-4 to increase ion permeability of tight junctions. Am. J. Pathol. 2011;179:807-818.

    Not in our library10.1016/j.ajpath.2011.05.001

  143. 143.

    Michikawa H, Fujita-Yoshigaki J, Sugiya H. Enhancement of barrier function by overexpression of claudin-4 in tight junctions of submandibular gland cells. Cell Tissue Res. 2008;334:255-264.

    Not in our library10.1007/s00441-008-0689-2

  144. 144.

    Pinton P, et al. Deoxynivalenol impairs porcine intestinal barrier function and decreases the protein expression of claudin-4 through a mitogen-activated protein kinase-dependent mechanism. J. Nutr. 2010;140:1956-1962.

    Not in our library10.3945/jn.110.123919

  145. 145.

    Sander GR, Cummins AG, Powell BC. Rapid disruption of intestinal barrier function by gliadin involves altered expression of apical junctional proteins. FEBS Lett. 2005;579:4851-4855.

    Not in our library10.1016/j.febslet.2005.07.066

  146. 146.

    Itallie CVan, Rahner C, Anderson JM. Regulated expression of claudin-4 decreases paracellular conductance through a selective decrease in sodium permeability. J. Clin. Investig. 2001;107:1319-1327.

    Not in our library10.1172/jci12464

  147. 147.

    Itallie CMVan, Fanning AS, Anderson JM. Reversal of charge selectivity in cation or anion-selective epithelial lines by expression of different claudins. Am. J. Physiol. - Ren. Physiol. 2003;285:1078-1084.

    Not in our library10.1152/ajprenal.00116.2003

  148. 148.

    Southgate J, et al. Differentiation potential of urothelium from patients with benign bladder dysfunction. Bone. 2008;23:1-7.

    Not in our library10.1111/j.1464-410x.2007.06795.x

  149. 149.

    Yu ASL, Enck AH, Lencer WI, Schneeberger EE. Claudin-8 expression in Madin-Darby canine kidney cells augments the paracellular barrier to cation permeation. J. Biol. Chem. 2003;278:17350-17359.

    Not in our library10.1074/jbc.m213286200

  150. 150.

    Carattino MD, et al. Bladder filling and voiding affect umbrella cell tight junction organization and function. Am. J. Physiol. Physiol. 2013;305:F1158-F1168.

    Not in our library10.1152/ajprenal.00282.2013

  151. 151.

    Hu A, Song BL. The interplay of Patched, Smoothened and cholesterol in Hedgehog signaling. Curr. Opin. Cell Biol. 2019;61:31-38.

    Not in our library10.1016/j.ceb.2019.06.008

  152. 152.

    Lavelle JP, et al. Urothelial pathophysiological changes in feline interstitial cystitis: a human model. Am. J. Physiol. - Ren. Physiol. 2000;278:540-553.

    Not in our library10.1152/ajprenal.2000.278.4.f540

  153. 153.

    Cross WR, Eardley I, Leese HJ, Southgate J. A biomimetic tissue from cultured normal human urothelial cells: analysis of physiological function. Am. J. Physiol. Ren. Physiol. 2005;289:459-468.

    Not in our library10.1152/ajprenal.00040.2005

  154. 154.

    Lewis SA, Diamond JM. Active sodium transport by mammalian urinary bladder. Nature. 1975;253:747-748.

    Not in our library10.1038/253747a0

  155. 155.

    Burton TJ, Elneil S, Nelson CP, Ferguson DR. Activation of epithelial Na+ channel activity in the rabbit urinary bladder by cAMP. Eur. J. Pharmacol. 2000;404:273-280.

    Not in our library10.1016/s0014-2999(00)00597-5

  156. 156.

    Ferguson DR, Kennedy I, Burton TJ. ATP is released from rabbit urinary bladder epithelial cells by hydrostatic pressure changes - A possible sensory mechanism? J. Physiol. 1997;505:503-511.

    Not in our library10.1111/j.1469-7793.1997.503bb.x

  157. 157.

    Wang ECYY, et al. Hydrostatic pressure-regulated ion transport in bladder uroepithelium. Am. J. Physiol. - Ren. Physiol. 2003;285:651-663.

    Not in our library10.1152/ajprenal.00403.2002

  158. 158.

    Hille B. Ionic channels in excitable membranes. Biophys. J. 1978;22:283-294.

    Not in our library10.1016/s0006-3495(78)85489-7

  159. 159.

    Ferguson DR. Urothelial function. BJU Int. 1999;84:235-242.

    Not in our library10.1046/j.1464-410x.1999.00187.x

  160. 160.
  161. 161.

    Kozono D, Yasui M, King LS, Agre P. Aquaporin water channels: atomic structure molecular dynamics meet clinical medicine. J. Clin. Investig. 2002;109:1395-1399.

    Not in our library10.1172/jci0215851

  162. 162.

    Fu D, Lu M. The structural basis of water permeation and proton exclusion in aquaporins (Review). Mol. Membr. Biol. 2007;24:366-374.

    Not in our library10.1080/09687680701446965

  163. 163.

    Rubenwolf PC, et al. Expression and Localisation of Aquaporin Water Channels in Human Urothelium In Situ and In Vitro. Eur. Urol. 2009;56:1013-1024.

    Not in our library10.1016/j.eururo.2008.08.013

  164. 164.

    Spector DA, Wade JB, Dillow R, Steplock DA, Weinman EJ. Expression, localization, and regulation of aquaporin-1 to -3 in rat urothelia. Am. J. Physiol. - Ren. Physiol. 2002;282:1034-1042.

    Not in our library10.1152/ajprenal.00136.2001

  165. 165.

    Sugiyama Y, Ota Y, Hara M, Inoue S. Osmotic stress up-regulates aquaporin-3 gene expression in cultured human keratinocytes. Biochim. Biophys. Acta. 2001;1522:82-88.

    Not in our library10.1016/s0167-4781(01)00320-7

  166. 166.

    Lucien N, et al. UT-B1 urea transporter is expressed along the urinary and gastrointestinal tracts of the mouse. Am. J. Physiol. - Regul. Integr. Comp. Physiol. 2005;288:1046-1056.

    Not in our library10.1152/ajpregu.00286.2004

  167. 167.

    Spector DA, Deng J, Stewart KJ. Hydration status affects urea transport across rat urothelia. Am. J. Physiol. - Ren. Physiol. 2011;301:1208-1217.

    Not in our library10.1152/ajprenal.00386.2011

  168. 168.

    Spector DA, Yang Q, Liu J, Wade JB. Expression, localization, and regulation of urea transporter B in rat urothelia. Am. J. Physiol. - Ren. Physiol. 2004;287:102-108.

    Not in our library10.1152/ajprenal.00442.2003

  169. 169.

    Spector DA, Yang Q, Wade JB. High urea and creatinine concentrations and urea transporter B in mammalian urinary tract tissues. Am. J. Physiol. - Ren. Physiol. 2007;292:467-474.

    Not in our library10.1152/ajprenal.00181.2006

  170. 170.

    Walser BL, Yagil Y, Jamison RL. Urea flux in the ureter. Am. J. Physiol. - Ren. Fluid Electrolyte Physiol. 1988;255:F244-F249.

    Not in our library10.1152/ajprenal.1988.255.2.f244

  171. 171.

    Rubenwolf PC, Georgopoulos NT, Kirkwood LA, Baker SC, Southgate J. Aquaporin Expression Contributes to Human Transurothelial Permeability In Vitro and Is Modulated by NaCl. PLoS ONE. 2012;7:e45339.

    Not in our library10.1371/journal.pone.0045339

  172. 172.

    Spector DA, Deng J, Stewart KJ. Hydration status affects sodium, potassium, and chloride transport across rat urothelia. Am. J. Physiol. - Ren. Physiol. 2013;305:1669-1679.

    Not in our library10.1152/ajprenal.00353.2013

  173. 173.

    Sugaya K, Ogawa Y, Nishizawa O, Groat WC. De Decrease in intravesical saline volume during isovolumetric cystometry in the rat. Neurourol. Urodyn. 1997;16:125-132.

    Not in our library10.1002/(sici)1520-6777(1997)16:2<125::aid-nau6>3.0.co;2-g

  174. 174.

    Morizawa Y, et al. Aquaporin-2 plays an important role in water transportation through the bladder wall in rats. Neurourol. Urodyn. 2018;37:2434-2440.

    Not in our library10.1002/nau.23715

  175. 175.

    Chen Y, et al. Rab27b is associated with fusiform vesicles and may be involved in targeting uroplakins to urothelial apical membranes. Proc. Natl Acad. Sci. USA. 2003;100:14012-14017.

    Not in our library10.1073/pnas.2436350100

  176. 176.

    Wankel B, et al. Sequential and compartmentalized action of Rabs, SNAREs, and MAL in the apical delivery of fusiform vesicles in urothelial umbrella cells. Mol. Biol. Cell. 2016;27:1621-1634.

    Not in our library10.1091/mbc.e15-04-0230

  177. 177.

    Gallo LI, et al. RAB27B requirement for stretch-induced exocytosis in bladder umbrella cells. Am. J. Physiol. - Cell Physiol. 2018;314:C349-C365.

    Not in our library10.1152/ajpcell.00218.2017

  178. 178.

    Khandelwal P, Ruiz WG, Apodaca G. Compensatory endocytosis in bladder umbrella cells occurs through an integrin-regulated and RhoA-and dynamin-dependent pathway. EMBO J. 2010;29:1961-1975.

    Not in our library10.1038/emboj.2010.91

  179. 179.

    Cavanaugh J, Oswari J, Margulies SS. Role of stretch on tight junction structure in alveolar epithelial cells. Am. J. Respir. Cell Mol. Biol. 2001;25:584-591.

    Not in our library10.1165/ajrcmb.25.5.4486

  180. 180.

    Thi MM, Tarbell JM, Weinbaum S, Spray DC. The role of the glycocalyx in reorganization of the actin cytoskeleton under fluid shear stress: A ‘bumper-car’ model. Proc. Natl Acad. Sci. USA. 2004;101:16483-16488.

    Not in our library10.1073/pnas.0407474101

  181. 181.

    Tzima E, et al. A mechanosensory complex that mediates the endothelial cell response to fluid shear stress. Nature. 2005;437:426-431.

    Not in our library10.1038/nature03952

  182. 182.

    Duan Y, et al. Shear-induced reorganization of renal proximal tubule cell actin cytoskeleton and apical junctional complexes. Proc. Natl Acad. Sci. USA. 2008;105:11418-11423.

    Not in our library10.1073/pnas.0804954105

  183. 183.

    Cohen TS, Lawrence GG, Khasgiwala A, Margulies SS. MAPk activation modulates permeability of isolated rat alveolar epithelial cell monolayers following cyclic stretch. PLoS ONE. 2010;5:e10385.

    Not in our library10.1371/journal.pone.0010385

  184. 184.

    Samak G, et al. Cyclic stretch disrupts apical junctional complexes in Caco-2 cell monolayers by a JNK-2-, c-Src-, and MLCK-dependent mechanism. Am. J. Physiol. - Gastrointest. Liver Physiol. 2014;306:947-958.

    Not in our library10.1152/ajpgi.00396.2013

  185. 185.

    Song MJ, Davidovich N, Lawrence GG, Margulies SS. Superoxide mediates tight junction complex dissociation in cyclically stretched lung slices. J. Biomech. 2016;49:1330-1335.

    Not in our library10.1016/j.jbiomech.2015.10.032

  186. 186.

    Pitelka DR, Hamamoto ST, Duafala JG, Nemanic MK. Cell contacts in the mouse mammary gland: i. Normal gland in postnatal development and the secretory cycle. 1973. J. Mammary Gland Biol. Neoplasia. 2009;14:295-316.

    Not in our library10.1007/s10911-009-9131-y

  187. 187.

    Pitelka DR, Taggart BN. Mechanical tension induces lateral movement of intramembrane components of the tight junction: studies on mouse mammary cells in culture. J. Cell Biol. 1983;96:606-612.

    Not in our library10.1083/jcb.96.3.606

  188. 188.

    Koga A, Todo S. Morphological and functional changes in the tight junctions of the bile canaliculi induced by bile duct ligation. Cell Tissue Res. 1978;195:267-276.

    Not in our library10.1007/bf00236724

  189. 189.

    Akao S, Oya M, Akiyama H, Ishikawa H. The tight junction of pancreatic exocrine cells is a morphometrically dynamic structure altered by intraductal hypertension. J. Gastroenterol. 2000;35:758-767.

    Not in our library10.1007/s005350070035

  190. 190.

    Apodaca G, Balestreire E, Birder LA. The Uroepithelial-associated sensory web. Kidney Int. 2007;72:1057-1064.

    Not in our library10.1038/sj.ki.5002439

  191. 191.

    Birder LA, de Groat WC. Mechanisms of disease: involvement of the urothelium in bladder dysfunction. Nat. Clin. Pract. Urol. 2007;4:46-54.

    Not in our library10.1038/ncpuro0672

  192. 192.

    Olsen SM, Stover JD, Nagatomi J. Examining the role of mechanosensitive ion channels in pressure mechanotransduction in rat bladder urothelial cells. Ann. Biomed. Eng. 2011;39:688-697.

    Not in our library10.1007/s10439-010-0203-3

  193. 193.

    Birder L, Andersson KE. Urothelial signaling. Physiol. Rev. 2013;93:653-680.

    Not in our library10.1152/physrev.00030.2012

  194. 194.

    Gonzalez EJ, Merrill L, Vizzard MA. Bladder sensory physiology: Neuroactive compounds and receptors, sensory transducers, and target-derived growth factors as targets to improve function. Am. J. Physiol. - Regul. Integr. Comp. Physiol. 2014;306:R869-R878.

    Not in our library10.1152/ajpregu.00030.2014

  195. 195.

    Arms L, Vizzard MA. Neuropeptides in lower urinary tract function. Handb. Exp. Pharm. 2011;202:395-423.

    Not in our library10.1007/978-3-642-16499-6_19

  196. 196.

    Hanna-Mitchell K-EALABAJKAT, Fry CH. Urothelial mucosal signaling and the overactive bladder. Neurourol. Urodyn. 2013;32:215-223.

    Not in our library10.1002/nau.22604

  197. 197.

    Li Y, et al. Expression and electrophysiological characteristics of P2X3 receptors in interstitial cells of Cajal in rats with partial bladder outlet obstruction. BJU Int. 2013;111:843-851.

    Not in our library10.1111/j.1464-410x.2012.11408.x

  198. 198.

    Michel MC, Vrydag W. Α 1-, Α 2- and Β-Adrenoceptors in the Urinary Bladder, Urethra and Prostate. Br. J. Pharmacol. 2006;147:88-119.

    Not in our library10.1038/sj.bjp.0706619

  199. 199.

    Mukerji G, et al. Localization of M2 and M3 Muscarinic Receptors in Human Bladder Disorders and Their Clinical Correlations. J. Urol. 2006;176:367-373.

    Not in our library10.1016/s0022-5347(06)00563-5

  200. 200.

    Beckel JM, Kanai A, Lee SJ, Groat WCDe, Birder LA. Expression of functional nicotinic acetylcholine receptors in rat urinary bladder epithelial cells. Am. J. Physiol. - Ren. Physiol. 2006;290:103-110.

    Not in our library10.1152/ajprenal.00098.2005

  201. 201.

    Dattilio A, Vizzard MA. Up-regulation of protease activated receptors in bladder after cyclophosphamide induced cystitis and colocalization with capsaicin receptor (VR1) in bladder nerve fibers. J. Urol. 2005;173:635-639.

    Not in our library10.1097/01.ju.0000143191.55468.1d

  202. 202.

    Corrow K, Girard BM, Vizzard MA. Expression and response of acid-sensing ion channels in urinary bladder to cyclophosphamide-induced cystitis. Am. J. Physiol. - Ren. Physiol. 2010;298:1130-1139.

    Not in our library10.1152/ajprenal.00618.2009

  203. 203.

    LaBerge J, Malley SE, Zvarova K, Vizzard MA. Expression of corticotropin-releasing factor and CRF receptors in micturition pathways after cyclophosphamide-induced cystitis. Am. J. Physiol. - Regul. Integr. Comp. Physiol. 2006;291:692-703.

    Not in our library10.1152/ajpregu.00086.2006

  204. 204.

    Qiao LY, Vizzard MA. Spinal cord injury-induced expression of TrkA, TrkB, phosphorylated CREB, and c-Jun in rat lumbosacral dorsal root ganglia. J. Comp. Neurol. 2005;482:142-154.

    Not in our library10.1002/cne.20394

  205. 205.

    Qiao LY, Vizzard MA. Cystitis-induced upregulation of tyrosine kinase (TrkA, TrkB) receptor expression and phosphorylation in rat micturition pathways. J. Comp. Neurol. 2002;454:200-211.

    Not in our library10.1002/cne.10447

  206. 206.

    Murray E, Malley SE, Qiao LY, Hu VY, Vizzard MA. Cyclophosphamide induced cystitis alters neurotrophin and receptor tyrosine kinase expression in pelvic ganglia and bladder. J. Urol. 2004;172:2434-2439.

    Not in our library10.1097/01.ju.0000143549.29867.4e

  207. 207.

    Deruyver Y, et al. Transient receptor potential channel modulators as pharmacological treatments for lower urinary tract symptoms (LUTS): Myth or reality? BJU Int. 2015;115:686-697.

    Not in our library10.1111/bju.12876

  208. 208.

    Skryma R, Prevarskaya N, Gkika D, Shuba Y. From urgency to frequency: facts and controversies of TRPs in the lower urinary tract. Nat. Rev. Urol. 2011;8:617-630.

    Not in our library10.1038/nrurol.2011.142

  209. 209.

    Merrill L, Girard BM, May V, Vizzard MA. Transcriptional and translational plasticity in rodent urinary bladder TRP channels with urinary bladder inflammation, bladder dysfunction, or postnatal maturation. J. Mol. Neurosci. 2012;48:744-756.

    Not in our library10.1007/s12031-012-9867-5

  210. 210.

    Charrua A, Cruz CD, Cruz F, Avelino A. Transient Receptor Potential Vanilloid Subfamily 1 is Essential for the Generation of Noxious Bladder Input and Bladder Overactivity in Cystitis. J. Urol. 2007;177:1537-1541.

    Not in our library10.1016/j.juro.2006.11.046

  211. 211.

    Charrua A, et al. Functional Transient Receptor Potential Vanilloid 1 is Expressed in Human Urothelial Cells. J. Urol. 2009;182:2944-2950.

    Not in our library10.1016/j.juro.2009.08.022

  212. 212.

    Gonzalez EJ, Arms L, Vizzard MA. The role(s) of cytokines/chemokines in urinary bladder inflammation and dysfunction. Biomed. Res. Int. 2014;2014:120525.

    Not in our library10.1155/2014/120525

  213. 213.

    Zarghooni S, et al. Expression of muscarinic and nicotinic acetylcholine receptors in the mouse urothelium. Life Sci. 2007;80:2308-2313.

    Not in our library10.1016/j.lfs.2007.01.046

  214. 214.

    Arms L, Girard BM, Vizzard MA. Expression and function of CXCL12/CXCR4 in rat urinary bladder with cyclophosphamide-induced cystitis. Am. J. Physiol. - Ren. Physiol. 2010;298:F589-F600.

    Not in our library10.1152/ajprenal.00628.2009

  215. 215.

    Arms L, Girard BM, Malley SE, Vizzard MA. Expression and function of CCL2/CCR2 in rat micturition reflexes and somatic sensitivity with urinary bladder inflammation. Am. J. Physiol. - Ren. Physiol. 2013;305:F111-F122.

    Not in our library10.1152/ajprenal.00139.2013

  216. 216.

    Birder LA. More than just a barrier: Urothelium as a drug target for urinary bladder pain. Am. J. Physiol. - Ren. Physiol. 2005;289:489-495.

    Not in our library10.1152/ajprenal.00467.2004

  217. 217.

    Birder, L.A. & Klumpp, D.J. Host responses to urinary tract infections and emerging therapeutics: Sensation and pain within the urinary tract. Urin. Tract Infect. Mol. Pathog. Clin. Manag. 565–588 (2016). 10.1128/9781555817404.ch23

    Not in our library10.1128/microbiolspec.uti-0023-2016

  218. 218.

    Burnstock G. Purinergic signalling in the lower urinary tract. Acta Physiol. 2013;207:40-52.

    Not in our library10.1111/apha.12012

  219. 219.

    Cockayne DA, et al. Urinary bladder hyporeflexia and reduced pain-related behaviour in P2X3-deficient mice. Nature. 2000;407:1011-1015.

    Not in our library10.1038/35039519

  220. 220.

    Clapham DE, Julius D, Montell C, Schultz G. International Union of Pharmacology. XLIX. Nomenclature and structure-function relationships of transient receptor potential channels. Pharmacol. Rev. 2005;57:427-450.

    Not in our library10.1124/pr.57.4.6

  221. 221.

    Merrill L, Gonzalez EJ, Girard BM, Vizzard MA. Receptors, channels, and signalling in the urothelial sensory system in the bladder. Nat. Rev. Urol. 2016;13:193-204.

    Not in our library10.1038/nrurol.2016.13

  222. 222.

    Igawa NATMY, Wyndaele J-J. The role of transient receptor potential ankyrin 1 (TRPA1) channel in activation of single unit mechanosensitive bladder afferent activities in the rat. Neurourol. Urodyn. 2013;32:215-223.

    Not in our library10.1002/nau.22449

  223. 223.

    Andersson KE, Gratzke C, Hedlund P. The role of the transient receptor potential (TRP) superfamily of cation-selective channels in the management of the overactive bladder. BJU Int. 2010;106:1114-1127.

    Not in our library10.1111/j.1464-410x.2010.09650.x

  224. 224.

    Yu W, Hill WG, Apodaca G, Zeidel ML. Expression and distribution of transient receptor potential (TRP) channels in bladder epithelium. Am. J. Physiol. - Ren. Physiol. 2011;300:49-59.

    Not in our library10.1152/ajprenal.00349.2010

  225. 225.

    Nilius TGWEB, et al. On the origin of bladder sensing: Tr(i)ps in urology. Neurourol. Urodyn. 2013;32:215-223.

    Not in our library10.1002/nau.20511

  226. 226.

    Nilius B, Owsianik G, Voets T, Peters JA. Transient receptor potential cation channels in disease. Physiol. Rev. 2007;87:165-217.

    Not in our library10.1152/physrev.00021.2006

  227. 227.

    Everaerts W, et al. Functional characterization of transient receptor potential channels in mouse urothelial cells. Am. J. Physiol. - Ren. Physiol. 2010;298:692-701.

    Not in our library10.1152/ajprenal.00599.2009

  228. 228.

    Birder LA, et al. Vanilloid receptor expression suggests a sensory role for urinary bladder epithelial cells. Proc. Natl Acad. Sci. 2001;98:13396-13401.

    Not in our library10.1073/pnas.231243698

  229. 229.

    Gevaert T, et al. Deletion of the transient receptor potential cation channel TRPV4 impairs murine bladder voiding. J. Clin. Investig. 2007;117:3453-3462.

    Not in our library10.1172/jci31766

  230. 230.

    Kullmann FA, et al. De Functional TRP and ASIC-like channels in cultured urothelial cells from the rat. Am. J. Physiol. - Ren. Physiol. 2009;296:892-901.

    Not in our library10.1152/ajprenal.90718.2008

  231. 231.

    Yamada T, et al. Differential localizations of the transient receptor potential channels TRPV4 and TRPV1 in the mouse urinary bladder. J. Histochem. Cytochem. 2009;57:277-287.

    Not in our library10.1369/jhc.2008.951962

  232. 232.

    Birder LA, et al. Activation of urothelial transient receptor potential vanilloid 4 by 4α-phorbol 12,13-didecanoate contributes to altered bladder reflexes in the rat. J. Pharmacol. Exp. Ther. 2007;323:227-235.

    Not in our library10.1124/jpet.107.125435

  233. 233.

    Mochizuki T, et al. The TRPV4 cation channel mediates stretch-evoked Ca2+ influx and ATP release in primary urothelial cell cultures. J. Biol. Chem. 2009;284:21257-21264.

    Not in our library10.1074/jbc.m109.020206

  234. 234.

    Streng T, et al. Distribution and Function of the Hydrogen Sulfide-Sensitive TRPA1 Ion Channel in Rat Urinary Bladder. Eur. Urol. 2008;53:391-400.

    Not in our library10.1016/j.eururo.2007.10.024

  235. 235.

    Stein RJ, et al. Cool (TRPM8) and hot (TRPV1) receptors in the bladder and male genital tract. J. Urol. 2004;172:1175-1178.

    Not in our library10.1097/01.ju.0000134880.55119.cf

  236. 236.

    Li, X., Hu, J., Zhao, X., Li, J. & Chen, Y. Piezo channels in the urinary system. Exp. Mol. Med. 18–20 (2022). 10.1038/s12276-022-00777-1

    Not in our library10.1038/s12276-022-00777-1

  237. 237.

    Marshall KL, et al. PIEZO2 in sensory neurons and urothelial cells coordinates urination. Nature. 2020;588:290-295.

    Not in our library10.1038/s41586-020-2830-7

  238. 238.

    Brierley SM, et al. Innate immune response to bacterial urinary tract infection sensitises high-threshold bladder afferents and recruits silent nociceptors. Pain. 2020;161:202-210.

    Not in our library10.1097/j.pain.0000000000001692

  239. 239.

    Coolen MJLL, Post E, Davis CC, Forney LJ. Characterization of microbial communities found in the human vagina by analysis of terminal restriction fragment length polymorphisms of 16S rRNA genes. Appl. Environ. Microbiol. 2005;71:8729-8737.

    Not in our library10.1128/aem.71.12.8729-8737.2005

  240. 240.

    Ravel J, et al. Vaginal microbiome of reproductive-age women. Proc. Natl Acad. Sci. USA. 2011;108:4680-4687.

    Not in our library10.1073/pnas.1002611107

  241. 241.

    Pfau A, Sacks T. The bacterial flora of the vaginal vestibule, urethra and vagina in the normal premenopausal woman. J. Urol. 1977;118:292-295.

    Not in our library10.1016/s0022-5347(17)57976-8

  242. 242.

    Foxman B. Epidemiology ofUrinary Tract Infections: Incidence, Morbidity, and Economic Costs. Nieren-.- und Hochdruckkrankheiten. 2007;36:252-257.

    Not in our library

  243. 243.

    Anderson GG, Dodson KW, Hooton TM, Hultgren SJ. Intracellular bacterial communities of uropathogenic Escherichia coli in urinary tract pathogenesis. Trends Microbiol. 2004;12:424-430.

    Not in our library10.1016/j.tim.2004.07.005

  244. 244.

    Litwin MS, et al. Urologic diseases in America project: Analytical methods and principal findings. J. Urol. 2005;173:933-937.

    Not in our library10.1097/01.ju.0000152365.43125.3b

  245. 245.

    Dielubanza EJ, Schaeffer AJ. Urinary tract infections in women. Med. Clin. North Am. 2011;95:27-41.

    Not in our library10.1016/j.mcna.2010.08.023

  246. 246.

    Ronald A. The etiology of urinary tract infection: Traditional and emerging pathogens. Dis.-a-Mon. 2003;49:71-82.

    Not in our library10.1067/mda.2003.8

  247. 247.

    Larue H, Ayari C, Bergeron A, Fradet Y. Toll-like receptors in urothelial cells - Targets for cancer immunotherapy. Nat. Rev. Urol. 2013;10:537-545.

    Not in our library10.1038/nrurol.2013.153

  248. 248.

    Becknell B, Schwaderer A, Hains DS, Spencer JD. Amplifying renal immunity: the role of antimicrobial peptides in pyelonephritis. Nat. Rev. Nephrol. 2015;11:642-655.

    Not in our library10.1038/nrneph.2015.105

  249. 249.

    Akira S, Uematsu S, Takeuchi O. Pathogen recognition and innate immunity. Cell. 2006;124:783-801.

    Not in our library10.1016/j.cell.2006.02.015

  250. 250.

    Zhang Z, Schluesener HJ. Mammalian toll-like receptors: from endogenous ligands to tissue regeneration. Cell. Mol. Life Sci. 2006;63:2901-2907.

    Not in our library10.1007/s00018-006-6189-1

  251. 251.

    Kawai T, Akira S. The role of pattern-recognition receptors in innate immunity: update on toll-like receptors. Nat. Immunol. 2010;11:373-384.

    Not in our library10.1038/ni.1863

  252. 252.

    Li X, Jiang S, Tapping RI. Toll‑like receptor signalling in cell proliferation and survival. Gerontology. 2015;61:515-525.

    Not in our library10.1016/j.cyto.2009.08.010

  253. 253.

    Song J, Abraham SN. Innate and adaptive immune responses in the urinary tract. Eur. J. Clin. Investig. 2008;38:21-28.

    Not in our library10.1111/j.1365-2362.2008.02005.x

  254. 254.

    Ayari C, Bergeron A, Larue H, Mnard C, Fradet Y. Toll-like receptors in normal and malignant human bladders. J. Urol. 2011;185:1915-1921.

    Not in our library10.1016/j.juro.2010.12.097

  255. 255.

    Zhou G, et al. Uroplakin Ia is the urothelial receptor for uropathogenic FimH binding. J. Cell Sci. 2001;22:4095-4103.

    Not in our library10.1242/jcs.114.22.4095

  256. 256.
  257. 257.

    Wang H, Min G, Glockshuber R, Sun TT, Kong XP. Uropathogenic E. coli Adhesin-Induced Host Cell Receptor Conformational Changes: Implications in Transmembrane Signaling Transduction. J. Mol. Biol. 2009;392:352-361.

    Not in our library10.1016/j.jmb.2009.06.077

  258. 258.

    Xie B, et al. Distinct glycan structures of uroplakins Ia and Ib: structural basis for the selective binding of FimH adhesin to uroplakin Ia. J. Biol. Chem. 2006;281:14644-14653.

    Not in our library10.1074/jbc.m600877200

  259. 259.

    Schembri MA, Kjaergaard K, Sokurenko EV, Klemm P. Molecular characterization of the Escherichia coli FimH adhesin. J. Infect. Dis. 2001;183:S28-S31.

    Not in our library10.1086/318847

  260. 260.

    Justice SS, et al. Differentiation and developmental pathways of uropathogenic Escherichia coli in urinary tract pathogenesis. Proc. Natl Acad. Sci. USA. 2004;101:1333-1338.

    Not in our library10.1073/pnas.0308125100

  261. 261.

    Elliott TS, Reed L, Slack RC, Bishop MC. Bacteriology and ultrastructure of the bladder in patients with urinary tract infections. J. Infect. 1985;11:191-9.

    Not in our library10.1016/s0163-4453(85)92997-4

  262. 262.

    Cheng Y, et al. Detection of intracellular bacteria in exfoliated urothelial cells from women with urge incontinence. Pathog. Dis. 2016;74:1-7.

    Not in our library10.1093/femspd/ftw067

  263. 263.

    Bäckhed F, Söderhäll M, Ekman P, Normark S, Richter-Dahlfors A. Induction of innate immune responses by Escherichia coli and purified lipopolysaccharide correlate with organ- and cell-specific expression of Toll-like receptors within the human urinary tract. Cell. Microbiol. 2001;3:153-158.

    Not in our library10.1046/j.1462-5822.2001.00101.x

  264. 264.

    Giglio D, et al. Downregulation of toll-like receptor 4 and IL-6 following irradiation of the rat urinary bladder. Clin. Exp. Pharmacol. Physiol. 2016;43:698-705.

    Not in our library10.1111/1440-1681.12583

  265. 265.

    Samuelsson P, Hang L, Wullt B, Irjala H, Svanborg C. Toll-like receptor 4 expression and cytokine responses in the human urinary tract mucosa. Infect. Immun. 2004;72:3179-3186.

    Not in our library10.1128/iai.72.6.3179-3186.2004

  266. 266.

    Song J, Bishop BL, Li G, Duncan MJ, Abraham SN. TLR4-Initiated and cAMP-Mediated Abrogation of Bacterial Invasion of the Bladder. Cell Host Microbe. 2007;1:287-298.

    Not in our library10.1016/j.chom.2007.05.007

  267. 267.

    Ashkar AA, Mossman KL, Coombes BK, Gyles CL, Mackenzie R. FimH adhesin of type 1 fimbriae is a potent inducer of innate antimicrobial responses which requires TLR4 and type 1 interferon signalling. PLoS Pathog. 2008;4:e1000233.

    Not in our library10.1371/journal.ppat.1000233

  268. 268.

    Ragnarsdóttir B, et al. Reduced toll-like receptor 4 expression in children with asymptomatic bacteriuria. J. Infect. Dis. 2007;196:475-484.

    Not in our library10.1086/518893

  269. 269.
  270. 270.

    Nagamatsu K, et al. Dysregulation of Escherichia coli α-hemolysin expression alters the course of acute and persistent urinary tract infection. Proc. Natl Acad. Sci. 2015;112:E871-E880.

    Not in our library10.1073/pnas.1500374112

  271. 271.

    Chromek M, et al. The antimicrobial peptide cathelicidin protects the urinary tract against invasive bacterial infection. Nat. Med. 2006;12:636-641.

    Not in our library10.1038/nm1407

  272. 272.

    Valore EV, et al. Human β-defensin-1: An antimicrobial peptide of urogenital tissues. J. Clin. Investig. 1998;101:1633-1642.

    Not in our library10.1172/jci1861

  273. 273.

    Danka ES, Hunstad DA. Cathelicidin augments epithelial receptivity and pathogenesis in experimental escherichia coli cystitis. J. Infect. Dis. 2015;211:1164-1173.

    Not in our library10.1093/infdis/jiu577

  274. 274.

    Spencer JD, et al. Ribonuclease 7, an antimicrobial peptide upregulated during infection, contributes to microbial defense of the human urinary tract. Kidney Int. 2013;83:615-625.

    Not in our library10.1038/ki.2012.410

  275. 275.

    Song J, et al. TLR4-mediated expulsion of bacteria from infected bladder epithelial cells. Proc. Natl Acad. Sci. USA. 2009;106:14966-14971.

    Not in our library10.1073/pnas.0900527106

  276. 276.

    Jaillon S, et al. The humoral pattern recognition molecule PTX3 is a key component of innate immunity against urinary tract infection. Immunity. 2014;40:621-632.

    Not in our library10.1016/j.immuni.2014.02.015

  277. 277.

    Bishop BL, et al. Cyclic AMP-regulated exocytosis of Escherichia coli from infected bladder epithelial cells. Nat. Med. 2007;13:625-630.

    Not in our library10.1038/nm1572

  278. 278.

    Pang Y, et al. Bladder epithelial cell phosphate transporter inhibition protects mice against uropathogenic Escherichia coli infection. Cell Rep. 2022;39:110698.

    Not in our library10.1016/j.celrep.2022.110698

  279. 279.

    Wang C, et al. A non-canonical autophagy-dependent role of the ATG16L1 T300A variant in urothelial vesicular trafficking and uropathogenic Escherichia coli persistence. Autophagy. 2019;15:527-542.

    Not in our library10.1080/15548627.2018.1535290

  280. 280.

    Bauckman KA, Mysorekar IU. Ferritinophagy drives uropathogenic Escherichia coli persistence in bladder epithelial cells. Autophagy. 2016;12:850-863.

    Not in our library10.1080/15548627.2016.1160176

  281. 281.

    Miao Y, Li G, Zhang X, Xu H, Abraham SN. A TRP channel senses lysosome neutralization by pathogens to trigger their expulsion. Cell. 2015;161:1306-1319.

    Not in our library10.1016/j.cell.2015.05.009

  282. 282.

    Joshi CS, Mora A, Felder PA, Mysorekar IU. NRF2 promotes urothelial cell response to bacterial infection by regulating reactive oxygen species and RAB27B expression. Cell Rep. 2021;37:109856.

    Not in our library10.1016/j.celrep.2021.109856

  283. 283.

    Sathiananthamoorthy S, et al. Reassessment of routine midstream culture in diagnosis of urinary tract infection. J. Clin. Microbiol. 2019;57:e01452-18.

    Not in our library10.1128/jcm.01452-18

  284. 284.

    Scott VCS, Haake DA, Churchill BM, Justice SS, Kim JH. Intracellular Bacterial Communities: A Potential Etiology for Chronic Lower Urinary Tract Symptoms. Urology. 2015;86:425-431.

    Not in our library10.1016/j.urology.2015.04.002

  285. 285.

    Daniels AM, Schulte AR, Herndon CM. Interstitial Cystitis: An Update on the Disease Process and Treatment. J. Pain. Palliat. Care Pharmacother. 2018;32:49-58.

    Not in our library10.1080/15360288.2018.1476433

  286. 286.

    Patnaik SS, et al. Etiology, pathophysiology and biomarkers of interstitial cystitis/painful bladder syndrome. Arch. Gynecol. Obstet. 2017;295:1341-1359.

    Not in our library10.1007/s00404-017-4364-2

  287. 287.

    Altuntas CZ, et al. Autoimmunity to uroplakin II causes cystitis in mice: A novel model of interstitial cystitis. Eur. Urol. 2012;61:193-200.

    Not in our library10.1016/j.eururo.2011.06.028

  288. 288.

    Keay S, et al. A mouse model for interstitial cystitis/painful bladder syndrome based on APF inhibition of bladder epithelial repair: A pilot study. BMC Urol. 2012;12:17.

    Not in our library10.1186/1471-2490-12-17

  289. 289.

    Hauser PJ, et al. Abnormal Expression of Differentiation-Related Proteins and Proteoglycan Core Proteins in the Urothelium of Interstitial Cystitis Patients. Laser Med Sci. 2009;24:777-786.

    Not in our library10.1016/j.juro.2007.09.022

  290. 290.

    Lv YS, et al. Intravesical hyaluronidase causes chronic cystitis in a rat model: A potential model of bladder pain syndrome/interstitial cystitis. Int. J. Urol. 2014;21:601-607.

    Not in our library10.1111/iju.12358

  291. 291.

    Funahashi Y, et al. Intravesical application of rebamipide promotes urothelial healing in a rat cystitis model. J. Urol. 2014;192:1864-1870.

    Not in our library10.1016/j.juro.2014.06.081

  292. 292.

    Zeng Y, et al. Uroplakin III-Delta4 Messenger RNA as a Promising Marker to Identify Nonulcerative Interstitial Cystitis. J. Urol. 2007;178:1322-1327.

    Not in our library10.1016/j.juro.2007.05.125

  293. 293.

    Golding H, Khurana S, Zaitseva M. What is the predictive value of animal models for vaccine efficacy in humans? The importance of bridging studies and species-independent correlates of protection. Cold Spring Harb. Perspect. Biol. 2018;10:a028902.

    Not in our library10.1101/cshperspect.a028902

  294. 294.
  295. 295.

    Birgersdotter A, Sandberg R, Ernberg I. Gene expression perturbation in vitro - A growing case for three-dimensional (3D) culture systems. Semin. Cancer Biol. 2005;15:405-412.

    Not in our library10.1016/j.semcancer.2005.06.009

  296. 296.

    Weaver VM, et al. Reversion of the malignant phenotype of human breast cells in three- dimensional culture and in vivo by integrin blocking antibodies. J. Cell Biol. 1997;137:231-245.

    Not in our library10.1083/jcb.137.1.231

  297. 297.

    Bhadriraju K, Chen CS. Engineering cellular microenvironments to improve cell-based drug testing. Drug Discov. Today. 2002;7:612-620.

    Not in our library10.1016/s1359-6446(02)02273-0

  298. 298.

    Baharvand H, Hashemi SM, Ashtiani SK, Farrokhi A. Differentiation of human embryonic stem cells into hepatocytes in 2D and 3D culture systems in vitro. Int. J. Dev. Biol. 2006;50:645-652.

    Not in our library10.1387/ijdb.052072hb

  299. 299.

    Benya PD, Shaffer JD. Dedifferentiated chondrocytes reexpress the differentiated collagen phenotype when cultured in agarose gels. Cell. 1982;30:215-224.

    Not in our library10.1016/0092-8674(82)90027-7

  300. 300.

    Nelson CM, Bissell MJ. Modeling dynamic reciprocity: Engineering three-dimensional culture models of breast architecture, function, and neoplastic transformation. Semin. Cancer Biol. 2005;15:342-352.

    Not in our library10.1016/j.semcancer.2005.05.001

  301. 301.

    Shield K, Ackland ML, Ahmed N, Rice GE. Multicellular spheroids in ovarian cancer metastases: Biology and pathology. Gynecol. Oncol. 2009;113:143-148.

    Not in our library10.1016/j.ygyno.2008.11.032

  302. 302.

    Zietarska AMagdalena, et al. Molecular Description of a 3D In Vitro Model for the Study of Epithelial Ovarian Cancer (EOC). Mol. Carcinog. 2006;967:957-967.

    Not in our library10.1002/mc.20315

  303. 303.

    Lee J, Cuddihy MJ, Kotov NA. Three-dimensional cell culture matrices: State of the art. Tissue Eng. - Part B Rev. 2008;14:61-86.

    Not in our library10.1089/teb.2007.0150

  304. 304.

    Georgopoulos NT, et al. Immortalisation of normal human urothelial cells compromises differentiation capacity. Eur. Urol. 2011;60:141-149.

    Not in our library10.1016/j.eururo.2011.02.022

  305. 305.

    Flieger A, Golka K, Schulze H, Föllmann W. Primary cultures of human urothelial cells for genotoxicity testing. J. Toxicol. Environ. Heal. - Part A Curr. Issues. 2008;71:930-935.

    Not in our library10.1080/15287390801988939

  306. 306.

    Dörrenhaus A, et al. Induction of unscheduled DNA synthesis in primary human urothelial cells by the mycotoxin ochratoxin A. Toxicol. Sci. 2000;53:271-277.

    Not in our library10.1093/toxsci/53.2.271

  307. 307.

    Southgate J, Hutton KAR, Thomas DFM, Trejdosiewicz LK. Normal human urothelial cells in vitro: Proliferation and induction of stratification. Lab. Investig. 1994;71:583-594.

    Not in our library

  308. 308.

    Lobban ED, et al. Uroplakin gene expression by normal and neoplastic human urothelium. Am. J. Pathol. 1998;153:1957-1967.

    Not in our library10.1016/s0002-9440(10)65709-4

  309. 309.

    Varley C, et al. Autocrine regulation of human urothelial cell proliferation and migration during regenerative responses in vitro. Exp. Cell Res. 2005;306:216-229.

    Not in our library10.1016/j.yexcr.2005.02.004

  310. 310.

    Scriven SD, Booth C, Thomas DFM, Trejdosiewicz LK, Southgate J. Discussion: Reconstitution of human urothelium from monolayer cultures. J. Urol. 1997;158:1153.

    Not in our library10.1016/s0022-5347(01)64408-2

  311. 311.

    Knowles MA, Finesilver A, Harvey AE, Berry RJH, M R. Long-Term Organ Culture of Normal Human Bladder. Cancer Res. 1983;43:374-385.

    Not in our library

  312. 312.

    Reznikoff CA, Johnson MD, Norback DH, Bryan GT. Growth and characterization of normal human urothelium in vitro. Vitro. 1983;19:326-343.

    Not in our library10.1007/bf02619511

  313. 313.

    Garthwaite M, et al. Use of donor bladder tissues for in vitro research. BJU Int. 2014;113:160-166.

    Not in our library10.1111/bju.12285

  314. 314.

    Southgate J, Masters JRW, Trejdosiewicz LK. Culture of Human Urothelium. Cult. Epithel. Cells. 2003;8:381-399.

    Not in our library

  315. 315.

    Baker SC, Shabir S, Southgate J. Biomimetic urothelial tissue models for the in vitro evaluation of barrier physiology and bladder drug efficacy. Mol. Pharm. 2014;11:1964-1970.

    Not in our library10.1021/mp500065m

  316. 316.

    Bolland F, Southgate J. Bio-engineering urothelial cells for bladder tissue transplant. Expert Opin. Biol. Ther. 2008;8:1039-1049.

    Not in our library10.1517/14712598.8.8.1039

  317. 317.

    Chapman EJ, et al. Expression of hTERT immortalises normal human urothelial cells without inactivation of the p16/Rb pathway. Oncogene. 2006;25:5037-5045.

    Not in our library10.1038/sj.onc.1209513

  318. 318.

    Shay JW. Telomerase therapeutics: Telomeres recognized as a DNA damage signal. Clin. Cancer Res. 2003;9:3521-3525.

    Not in our library

  319. 319.

    Horsley H, Dharmasena D, Malone-Lee J, Rohn JL. A urine-dependent human urothelial organoid offers a potential alternative to rodent models of infection. Sci. Rep. 2018;8:1-14.

    Not in our library10.1038/s41598-018-19690-7

  320. 320.

    Jafari, N. V & Rohn, J. L. An immunoresponsive three-dimensional urine-tolerant human urothelial (3D-UHU) model to study urinary tract infection. bioRxiv (2022). 10.1101/2022.07.22.501108

    Not in our library10.3389/fcimb.2023.1128132

  321. 321.

    Sutherland G, Bain A. Culture of Cells from the Urine of Newborn Children. Nature. 1972;239:231.

    Not in our library10.1038/239231a0

  322. 322.
  323. 323.

    Nagele U, et al. In Vitro Investigations of Tissue-Engineered Multilayered Urothelium Established from Bladder Washings. Eur. Urol. 2008;54:1414-1422.

    Not in our library10.1016/j.eururo.2008.01.072

  324. 324.

    Fossum M, Skikuniene J, Orrego A, Nordenskjöld A. Prepubertal follow-up after hypospadias repair with autologous in vitro cultured urothelial cells. Acta Paediatr. Int. J. Paediatr. 2012;101:755-760.

    Not in our library10.1111/j.1651-2227.2012.02659.x

  325. 325.

    Detrisac CJ, Mayfield RK, Colwell JA, Garvin AJ, Sens DA. In vitro culture of cells exfoliated in the urine by patents with diabetes mellitus. J. Clin. Investig. 1983;71:170-173.

    Not in our library10.1172/jci110747

  326. 326.

    RHEINWALD JG, O’CONNELL TM. Intermediate Filament Proteins as Distinguishing Markers of Cell Type and Differentiated State in Cultured Human Urinary Tract Epithelia. Ann. N. Y. Acad. Sci. 1985;455:259-267.

    Not in our library10.1111/j.1749-6632.1985.tb50416.x

  327. 327.

    Bharadwaj S, et al. Characterization of urine-derived stem cells obtained from upper urinary tract for use in cell-based urological tissue engineering. Tissue Eng. - Part A. 2011;17:2123-2132.

    Not in our library10.1089/ten.tea.2010.0637

  328. 328.

    Bharadwaj S, et al. Multipotential differentiation of human urine-derived stem cells: Potential for therapeutic applications in urology. Stem Cells. 2013;31:1840-1856.

    Not in our library10.1002/stem.1424

  329. 329.

    Ho PL, Kurtova A, Chan KS. Normal and neoplastic urothelial stem cells: Getting to the root of the problem. Nat. Rev. Urol. 2012;9:583-594.

    Not in our library10.1038/nrurol.2012.142

  330. 330.

    Zhang Y, et al. Urine Derived Cells are a Potential Source for Urological Tissue Reconstruction. J. Urol. 2008;180:2226-2233.

    Not in our library10.1016/j.juro.2008.07.023

  331. 331.

    Zhang M, et al. The differentiation of human adipose-derived stem cells towards a urothelium-like phenotype in vitro and the dynamic temporal changes of related cytokines by both paracrine and autocrine signal regulation. PLoS ONE. 2014;9:e95583.

    Not in our library10.1371/journal.pone.0095583

  332. 332.

    Ning J, Li C, Li H, Chang J. Bone marrow mesenchymal stem cells differentiate into urothelial cells and the implications for reconstructing urinary bladder mucosa. Cytotechnology. 2011;63:531-539.

    Not in our library10.1007/s10616-011-9376-3

  333. 333.

    Kang HH, Kang JJ, Kang HG, Chung SS. Urothelial differentiation of human amniotic fluid stem cells by urothelium specific conditioned medium. Cell Biol. Int. 2014;38:531-537.

    Not in our library10.1002/cbin.10232

  334. 334.

    Chung SS, Koh CJ. Bladder cancer cell in co-culture induces human stem cell differentiation to urothelial cells through paracrine FGF10 signaling. Vitr. Cell. Dev. Biol. - Anim. 2013;49:746-751.

    Not in our library10.1007/s11626-013-9662-9

  335. 335.

    Wu S, et al. Urothelial Differentiation of Human Umbilical Cord-Derived Mesenchymal Stromal Cells In Vitro. Anal. Cell. Pathol. 2013;36:63-69.

    Not in our library10.1155/2013/274640

  336. 336.

    Kang M, Kim HH, Han YM. Generation of bladder urothelium from human pluripotent stem cells under chemically defined serum- and feeder-free system. Int. J. Mol. Sci. 2014;15:7139-7157.

    Not in our library10.3390/ijms15057139

  337. 337.

    Kim E, et al. Creation of bladder assembloids mimicking tissue regeneration and cancer. Nature. 2020;588:664-669.

    Not in our library10.1038/s41586-020-3034-x

  338. 338.
  339. 339.

    Andersen TE, et al. Escherichia coli uropathogenesis In vitro: Invasion, cellular escape, and secondary infection analyzed in a human bladder cell infection model. Infect. Immun. 2012;80:1858-1867.

    Not in our library10.1128/iai.06075-11

  340. 340.

    Iosifidis G, Duggin IG. Distinct morphological fates of uropathogenic Escherichia coli intracellular bacterial communities: Dependency on urine composition and pH. Infect. Immun. 2020;88:1-16.

    Not in our library10.1128/iai.00884-19

  341. 341.

    Tan CK, et al. Genome-wide mapping of cystitis due to Streptococcus agalactiae and Escherichia coli in mice identifies a unique bladder transcriptome that signifies pathogen-specific antimicrobial defense against urinary tract infection. Infect. Immun. 2012;80:3145-3160.

    Not in our library10.1128/iai.00023-12

  342. 342.

    Martínez-Figueroa C, Cortés-Sarabia K. Carmen Alarcón-Romero, L. Del, Catalán-Nájera, H. G., Martínez-Alarcón, M. & Vences-Velázquez, A. Observation of intracellular bacterial communities in urinary sediment using brightfield microscopy; A case report. BMC Urol. 2020;20:1-5.

    Not in our library10.1186/s12894-020-00661-y

  343. 343.
  344. 344.

    Reitzer L, Zimmern P. Rapid growth and metabolism of uropathogenic escherichia coli in relation to urine composition. Clin. Microbiol. Rev. 2020;33:e00101-19.

    Not in our library10.1128/cmr.00101-19

  345. 345.

    Vasyutin I, Zerihun L, Ivan C, Atala A. Bladder organoids and spheroids: Potential tools for normal and diseased tissue modelling. Anticancer Res. 2019;39:1105-1118.

    Not in our library10.21873/anticanres.13219

  346. 346.

    Mullenders J, et al. Mouse and human urothelial cancer organoids: A tool for bladder cancer research. Proc. Natl Acad. Sci. USA. 2019;116:4567-4574.

    Not in our library10.1073/pnas.1803595116

  347. 347.

    Justice BA, Badr NA, Felder RA. 3D cell culture opens new dimensions in cell-based assays. Drug Discov. Today. 2009;14:102-107.

    Not in our library10.1016/j.drudis.2008.11.006

  348. 348.

    Reininger-mack A, Thielecke H, Robitzki AA. 3D-biohybrid systems: applications in drug screening. Trends Biotechnol. 2002;20:56-61.

    Not in our library10.1016/s0167-7799(01)01880-7

  349. 349.

    Sun T, Jackson S, Haycock JW, MacNeil S. Culture of skin cells in 3D rather than 2D improves their ability to survive exposure to cytotoxic agents. J. Biotechnol. 2006;122:372-381.

    Not in our library10.1016/j.jbiotec.2005.12.021

  350. 350.
  351. 351.

    Sharma K, et al. Dynamic persistence of intracellular bacterial communities of uropathogenic escherichia coli in a human bladder-chip model of urinary tract infections. Elife. 2021;10:1-30.

    Not in our library10.7554/elife.66481

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