Host pathogenesis in urinary tract infections.

Urinary tract infections (UTIs) are the result of an interaction between bacterial virulence and host defense factors that compete to invade or protect the host, respectively. Research over the past 30 years has demonstrated that vaginal colonization with uropathogens precedes most UTIs. Receptivity of the vaginal mucosa for uropathogens is an essential initial step in vaginal mucosa colonization. When vaginal and buccal epithelial cells were collected from patients susceptible to reinfection and compared with such cells obtained from controls resistant to UTIs, the strains that caused cystitis adhered much more avidly to the epithelial cells from susceptible women. These genotypic traits for epithelial cell receptivity may be a major susceptibility factor in UTIs. The presence or absence of blood group determinants on the surface of uroepithelial cells may influence an individual's susceptibility to UTIs. The protective effect in women with the secretor phenotype may be due to fucosylated structures at the cell surface which decrease the availability of putative receptors for Escherichia coli. Susceptibility among women who do not secrete blood group antigens may be due to specific E. coli-binding glycolipids that are absent in women who secrete blood group antigens. Recent studies have shown that the vaginal fluid, which forms an interface between uropathogens and epithelial cells, also influences vaginal colonizations.

IL-1beta and TNF-alpha in prostatic secretions are indicators in the evaluation of men with chronic prostatitis.

PURPOSE: Chronic Prostatitis, or Chronic Pelvic Pain Syndrome [CPPS], is a common disorder characterized by pelvic pain and varying degrees of inflammation in expressed prostatic secretions (EPS). In search of markers to more clearly define CPPS, we compared proinflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) levels in EPS from men with CPPS, to healthy men and men with Benign Prostatic Hyperplasia (BPH). METHODS: 78 men: controls (n = 16), BPH (n = 14), CPPS IIIA [>/=10 white blood cells per high power field (WBC/hpf) in EPS] (n = 18), CPPS IIIB [<10 WBC/hpf in EPS] (n = 20), and asymptomatic inflammatory prostatitis (AIP) (n = 10) were evaluated for EPS WBC, and IL-1beta and TNF-alpha by ELISA. RESULTS: IL-1beta and TNF-alpha levels in EPS were usually detectable in men with CPPS IIIA (89% and 45%, respectively) or AIP (90%; 100%), but less often in controls (31%; 17%), BPH (57%; 15%), and CPPS IIIB (35%; 15%) respectively. IL-1beta and TNF-alpha levels were higher in CPPS IIIA versus CPPS IIIB, and in AIP versus controls or BPH (p's <0.001). Cut-points for IL-1beta and TNF-alpha discriminated AIP from controls (predictive values = 94% and 83%, respectively) and CPPS IIIA from CPPS IIIB (predictive values 84% and 100%). Overall, there was a correlation between IL-1beta and TNF-alpha (p <0.003), but no correlation between WBC and IL-1beta (p <0.1) or TNF-alpha (p <0.50). CONCLUSIONS: Cytokines are frequently present and elevated in the EPS from men with CPPS IIIA and AIP and provide a novel means for identification, characterization and potential management of men with CPPS that differs from traditional methods based on WBC.

Characterization of an immortalized human vaginal epithelial cell line.

PURPOSE: Adherence of type 1 piliated Escherichia coli to vaginal mucosa plays a major role in the pathogenesis of ascending urinary tract infections (UTIs) in women. Progress in understanding the mechanism of adherence to the vaginal surface could be enhanced by the utilization of well-characterized vaginal epithelial cells. The objective of this study was to immortalize vaginal epithelial cells and study their bacterial adherence properties. MATERIALS AND METHODS: Primary vaginal cells were obtained from a normal post-menopausal woman, immortalized by infection with E6/E7 genes from human papillomavirus 16 (HPV 16) and cultured in serum free keratinocyte growth factor medium. RESULTS: Positive immunostaining with a pool of antibodies to cytokeratins 1, 5, 10 and 14 (K1, K5, K10 and K14) and to K13 confirmed the epithelial origin of these cells. The immortalized cells showed binding of type 1 piliated E. coli in a pili specific and mannose sensitive manner. CONCLUSION: This model system should facilitate studies on the interaction of pathogens with vaginal mucosal cells, an essential step in the progression of ascending UTIs in women.

Roles of glycoproteins and oligosaccharides found in human vaginal fluid in bacterial adherence.

Adherence of type 1-piliated Escherichia coli to carbohydrate structures of vaginal mucosa plays a major role in the pathogenesis of ascending urinary tract infections in women. Colonization of the vaginal introitus is influenced by interactions between pathogens, vaginal fluid, and vaginal epithelium. In this study, the type and amount of carbohydrates and glycoproteins present in vaginal fluid were determined. Free and protein-bound oligosaccharides in vaginal fluid specimens were analyzed by fluorophore-assisted carbohydrate electrophoresis (FACE) and high-pressure liquid chromatography (HPLC). Two-dimensional electrophoretic separations of vaginal fluid glycoproteins were performed together with bacterial overlay assays. The results of FACE showed that the majority of the oligosaccharides are in the free state and the bound oligosaccharides are undetectable. HPLC analysis of free sugars revealed glucose as the major sugar (3.3 +/- 0.3 mM), and the concentrations of mannose and glucosamine were 0.065 +/- 0.04 and 0.02 +/- 0.001 mM, respectively. Radiolabeled E. coli bound three vaginal fluid glycoproteins with the following molecular masses and pIs: 82 kDa and pI 5.5, 55 kDa and pI 4.5, and 55 kDa and pI 6.5. The binding was inhibited by mannose and by deglycosylation of the proteins prior to the overlay assay. One of these putative receptors was identified to be the heavy chain of secretory IgA (S-IgA). These data suggest that the free mannose in the fluid is less than that required to affect E. coli-epithelial cell binding interactions and that S-IgA may bind E. coli in the vaginal introitus.