Uropathogenic E coli infection of the male urogenital tract in wild type and TLR4KO mice

OLIVERA CAROLINA; GLORIA JANET GODOY; FLORENCIA CELESTE SALAZAR; LEONARDO RODOLFO SÁNCHEZ; RUBÉN DARÍO MOTRICH; VIRGINIA ELENA RIVERO

Mar del Plata

Congreso; LXIV REUNIÓNANUAL DE SAI; 2016

Sociedad Argentina de Inmunologia

Uropathogenic Escherichia coli infection of male genitourinary tract in wild type and TLR4-/- mice Carolina Olivera1, Gloria Janet Godoy1, Florencia Salazar1, Leonardo Rodolfo Sanchez, Ruben Dario Motrich1, Virginia Elena Rivero1CIBICI-CONICET. Facultad de Ciencias Químicas. Universidad Nacional de Córdoba. ArgentinaUrinary tract infections are among the most common infections in men being the uropathogenic Escherichia coli bacteria the microorganisms most frequently isolated. Male lower and upper genitourinary tract could be affected being the reflux of urine into the intra-prostatic ducts a potential route of access for the uropathogenic bacteria. In the present study we analyzed the development of pain, bacterial spread and inflammation after transurethral instillation of saline or 1x 108 E. coli 1677 into adult C57BL/6 and TLR4-/- mice. Pain was assayed as tactile allodynia using Von Frey filaments at different time points after infection. In addition, urethra and prostate tissues were harvested from saline or E-coli-infected mice and the presence of the bacteria and leukocyte infiltration analyzed by bacterial count and immune staining followed by flow cytometry respectively. Pelvic pain development was evidenced by increased allodynia responses in the pelvic region of E coli infected mice. Bacterial inoculation resulted in an ascending infection of the male genital tract in both strains: C57BL/6 and TLR4-/- mice. Urethral bacterial loads were similar between strains, while higher counts were detected in prostate tissue from TLR4-/-mice when compared to C57BL/6 (p<0.05). The analysis of leukocyte infiltration revealed the presence of CD45+ cells in urethra and prostate from both strains being GR1+, F480+ and CD11b+ cells the main infiltrating populations detected, with only low proportions of CD3+ and CD19+ cells. Our results show that transurethral inoculation of uropathogenic E. coli 1677 reliably infects the lower and upper male genital tract showing an ascendant pattern that is accompanied by local inflammation and pelvic pain development. In addition, our results suggest that immune mechanisms triggered by TLR4 are important for an efficient bacterial clearance.