914 IN VIVO ROLE OF RAB27B IN UROTHELIAL ADHESION AND INVASION BY UROPATHOGENIC E.COLI

Abstract

You have accessJournal of UrologyInfections/Inflammation of the Genitourinary Tract: Kidney & Bladder1 Apr 2012914 IN VIVO ROLE OF RAB27B IN UROTHELIAL ADHESION AND INVASION BY UROPATHOGENIC E.COLI Duane Hickling, Yan Liu, Victor Nitti, Herbert Lepor, Tung-Tien Sun, Gert Kreibich, and Xue-Ru Wu Duane HicklingDuane Hickling New York, NY More articles by this author , Yan LiuYan Liu New York, NY More articles by this author , Victor NittiVictor Nitti New York, NY More articles by this author , Herbert LeporHerbert Lepor New York, NY More articles by this author , Tung-Tien SunTung-Tien Sun New York, NY More articles by this author , Gert KreibichGert Kreibich New York, NY More articles by this author , and Xue-Ru WuXue-Ru Wu New York, NM More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2012.02.1010AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Uropathogenic E. coli (UPEC) can adhere to and invade urothelial cells. This process is critical to the formation of intracellular bacterial communities (IBCs) and quiescent intracellular reservoirs (QIRs), potentially important sources of recurrent urinary tract infection (UTI). Uroplakin Ia (UPIa) is the putative urothelial receptor for UPEC binding but the molecular bases underlying invasion remain poorly understood. Rab27b belongs to a family of membrane-associated GTPases that coordinate host cell signal transduction, cytoskeletal organization, and vesicular traffic. Rab27b is highly expressed in the urothelium and Bishop and colleagues recently showed that UPECs exist in urothelial cytoplasmic vesicles positive for Rab27b and UPIa. However, in vivo evidence is still lacking as to what exact roles Rab27b plays in the invasion of UPEC into the urothelial cell. METHODS Ascending UTI experiments were performed using Rab 27b knockout (KO) mice, lacking urothelial Rab27b expression, and wild-type (WT) control mice. 6-9 wk old females were inoculated, transurethrally, with a UPEC cystitis strain UTI89. Mice (5/genotype/time point) were sacrificed at 1, 12, 32 h post-infection and subject to antibody staining and Western blotting to identify and quantify UPEC, uroplakins and extent of apoptosis. RESULTS Rab27b KO mice had significantly fewer UPECs attached to the urothelial surface at 1 h post-inoculation when compared to WT mice. At 12 h post-inoculation, the superficial urothelial cells of WT mice harbored a large number of IBCs whereas Rab27b KO urothelial cells were almost devoid of IBCs. This trend held at 32 h post-inoculation, as there were considerably fewer QIRs in Rab27b KO versus WT mice. Additionally, urothelial cells of the Rab27b KO mice expressed significantly lower level of UPIa and sustained less apoptosis in response to UPEC. CONCLUSIONS Our data provide the first in vivo evidence implicating Rab27b as an important player in UTI pathogenesis. Rab27b affects the expression of urothelial receptors for UPECs and potentially alters UPEC invasion into and/or exit from the urothelium. Because intracellular vesicular trafficking mediated by molecules like Rab27b is affected in various human genetic diseases, it will be of interest to determine if patients with these conditions are more prone or resistant to UTI. © 2012 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 187Issue 4SApril 2012Page: e372-e373 Peer Review Report Advertisement Copyright & Permissions© 2012 by American Urological Association Education and Research, Inc.MetricsAuthor Information Duane Hickling New York, NY More articles by this author Yan Liu New York, NY More articles by this author Victor Nitti New York, NY More articles by this author Herbert Lepor New York, NY More articles by this author Tung-Tien Sun New York, NY More articles by this author Gert Kreibich New York, NY More articles by this author Xue-Ru Wu New York, NM More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...