Background The pathophysiology of interstitial cystitis (IC) is unknown. Deficits in urothelial cell layers and autoimmune mechanisms may play a role. Objective To examine whether immunization of mice with recombinant mouse uroplakin II (rmUPK2), a bladder-specific protein, would provoke an autoimmune response sufficient to create an IC phenotype. Design, setting, and participants RmUPK2 complementary DNA was generated, transferred into a bacterial expression vector, and the generated protein was purified. Eight-week-old SWXJ female mice were immunized with rmUPK2 protein via subcutaneous injection of 200 µg of rmUPK2 protein in 200 µl of an emulsion. Measurements Mice were euthanized 5 wk after immunization. Axillary and inguinal lymph node cells were tested for antigen-specific responsiveness and cytokine production, serum isotype antibody titers against rmUPK2 were determined, and gene expression of inflammatory mediators was measured in the bladder and other organs. For functional analysis, mice were placed in urodynamic chambers for 24-h micturition frequency and total voided urine measurements. Results and limitations Immunization with rmUPK2 resulted in T-cell infiltration of the bladder urothelium and increased rmUPK2-specific serum antibody responses in the experimental autoimmune cystitis (EAC) mice models compared with controls. The ratio of bladder to body weight was increased in EAC mice. Quantitative reverse transcriptase polymerase chain reaction analysis showed elevated gene expression of tumor necrosis factor α, interferon γ, interleukin (IL)-17A, and IL-1β in bladder urothelium but not in other organs. Evaluation of 24-h micturition habits of EAC mice showed significantly increased urinary frequency (p < 0.02) and significantly decreased urine output per void (p < 0.021) when compared with control mice. Conclusions Our study showed that a bladder-specific autoimmune response sufficient to induce inflammation and EAC occurs in mice following immunization with rmUPK2. EAC mice displayed significant evidence of urinary frequency and decreased urine output per void. Further phenotype characterization of EAC mice should include evidence for pain and/or afferent hypersensitivity, and evidence of urothelial cell layer damage.

OBJECTIVE To examine bladder function in a newly developed experimental autoimmune cystitis (EAC) model in female SWXJ strain mice, as a potential animal model for interstitial cystitis (IC). MATERIALS AND METHODS In all, 20 SWXJ female mice were divided into two groups: an EAC group immunized with mouse bladder homogenate in complete Freund’s adjuvant (CFA) and a control group immunized with CFA alone. At 4 months after injection, the bladder function of some mice (six) was studied with 24‐h micturition habits using metabolic cages and conscious cystometrography (CMG). The bladder and lung were harvested for histological examination and to assess interferon‐γ (IFN‐γ) mRNA expression. RESULTS Histology examination showed obviously thickened lamina propria, infiltration of lymphocytes, giant cells, and increased mast cells in the detrusor muscle of the EAC mice. The lungs of EAC mice showed normal histology. The IFN‐γ mRNA expression increased significantly in the bladder, but not in the lung of the EAC mice. The 24‐h micturition habits measurements showed increased frequency of urination in the EAC mice compared with the controls. Similarly, CMG showed decreased intercontraction intervals and voided volumes per micturition in the EAC mice compared with the controls. However, there were no significant differences in peak voiding pressure or total voiding volume between the EAC and control mice. CONCLUSIONS Our murine EAC model has comparable functional and histological alterations to those seen in human IC, and may provide a useful model for the study of the pathogenesis and treatment of IC.

Abbreviations & Acronyms CMG = cystometrogram Con 3w = 3 weeks agematched controls Con 11w = 11 weeks agematched controls DBD = diabetic bladder dysfunction DIU = 5% sucrose-induced diuresis DIU 3w = 3 weeks after 5% sucrose-induced diuresis DIU 3 + 8w = 3 weeks after 5% sucrose-induced diuresis followed by 5% sucrose removal for 8 weeks DIU 11w = 11 weeks after 5% sucrose-induced diuresis DM = diabetes mellitus DM 3w = 3 weeks after streptozotocin-induced diabetes mellitus DM 3 + 8w = 3 weeks after streptozotocin-induced diabetes mellitus followed by insulin replacement treatment for 8 weeks DM 11w = 11 weeks after streptozotocin-induced diabetes mellitus HbA1c = glycated hemoglobin A1c STZ = streptozotocin Objectives: To determine whether diabetes mellitus-and diuresis-induced alterations in the bladder can be reversed in rats. Methods: Male Sprague-Dawley rats were randomly distributed into eight groups (n = 16 per group): 3 weeks and 11 weeks age-matched controls, 3 weeks and 11 weeks after streptozotocin-induced diabetes mellitus, 3 weeks after diabetes mellitus induction then treated with insulin for 8 weeks, 3 weeks and 11 weeks after 5% sucrose-induced diuresis, and 3 weeks after 5% sucrose-induced diuresis followed by removal of 5% sucrose for 8 weeks. Bodyweight, blood glucose and glycated hemoglobin A1c were monitored. At the designated time-points, 24-h urinary habits were examined, and cystometry was carried out in half of the animals. The bladders from the remaining animals were harvested for histological examination, and quantification of smooth muscle, urothelium and collagen components. Results: Insulin treatment reversed hyperglycemia and polyuria in diabetic animals successfully, which was shown by normalization of blood glucose, glycated hemoglobin A1c and 24-h urinary habits. Subsequently, bodyweight, bladder weight and percentage change of bladder components (smooth muscle, collagen, urothelium) in total bladder crosssectional area were reversed to almost normal levels, and the bladder dysfunction was mostly reversed by 8 weeks of glycemic control, seen in the cystometry study. Similar alterations and reversed effects were seen in diuretic rats without and with 5% sucrose removal, respectively. Conclusions: Short-term (3-week induction) diabetes-and polyuria-induced functional and morphological alterations of the bladder can mostly be reversed in rats.Key words: bladder, diabetes, insulin, morphology, smooth muscle. IntroductionDBD, a collective description of clinical symptoms, including decreased sensation, increased capacity, poor emptying 1 and detrusor overactivity, 2 is among the most common and costly complications of DM.3 It is estimated that DBD occurs in approximately 87% of individuals diagnosed with DM, a higher rate than that of widely recognized complications such as neuropathy (60%) and nephropathy (50%).1,3 Although DBD is not life threatening, it substantially affects quality of life. 4The classic symptoms of untreated DM are loss of weight, polyuria, polydipsia and polypha...

The cause of chronic pelvic pain in interstitial cystitis/painful bladder syndrome (IC/PBS) remains unclear; autoimmunity is a possible etiology. We have recently shown that injection of a single immunogenic peptide of uroplakin 3A (UPK3A 65-84) induces experimental autoimmune cystitis (EAC) in female BALB/cJ mice that is unique among experimental models in accurately reflecting both the urinary symptoms and pelvic pain of IC/PBS. The aim of this project was to identify the roles of mast cells and mast cell chemoattractant/activator monocyte chemoattractant protein-1 [chemokine (C-C motif) ligand 2 (CCL2)] in the allodynia in this model. We immunized 6- to 8-wk-old female BALB/cJ mice with UPK3A 65-84 peptide and, 5–40 days later, observed increased responses to stimulation of the suprapubic abdominal and hindpaw surfaces with von Frey monofilaments compared with mice injected with adjuvant alone. Suprapubic and hindpaw tactile allodynia responses by EAC mice were blocked by instillation of lidocaine into the bladder but not by lidocaine in the uterus, confirming the bladder as the source of the hypersensitivity. Markedly increased numbers of activated mast cells and expression of CCL2 were found in the bladder after immunization with UPK3A 65-84. Hypersensitive responses were inhibited by mast cell stabilizer cromolyn sodium and antagonists of histamine receptors 1 and 2. Furthermore, BALB/cJ mice with deletion of the Ccl2 or chemokine (C-C motif) receptor 2 gene exhibited markedly reduced allodynia and accumulation of mast cells after UPK3A 65-84 immunization. These results show that UPK3A 65-84 immunization causes chronic visceral allodynia and suggest that it is mediated by CCL2-driven mast cell accumulation in the bladder.