Characterization ofV.choleraeT3SS-dependent cytotoxicity in cultured intestinal epithelial cells

• DOI: 10.1111/cmi.12629
• Publication Date: 2016-06-15T14:20:30Z
• Authors: Kelly A. Miller; Mudit Chaand; Stacy Gregoire; Takeshi Yoshida; Lisa A. Beck; Andrei I. Ivanov; Michelle Dziejman
• Keywords: 0301 basic medicine; Cell Death; Virulence; Gene Expression Regulation, Bacterial; 3. Good health; Bile Acids and Salts; 03 medical and health sciences; Bacterial Proteins; Osmotic Pressure; Host-Pathogen Interactions; Type III Secretion Systems; Bile; Humans; Caco-2 Cells; Vibrio cholerae; Gene Deletion; Signal Transduction

AM-19226 is a pathogenic, non-O1/non-O139 serogroup strain of Vibrio cholerae that uses Type 3 Secretion System (T3SS) mediated mechanism to colonize host tissues and disrupt homeostasis, causing cholera. Co-culturing the Caco2-BBE human intestinal epithelial cell line with in presence bile results rapid mammalian death requires functional T3SS. We examined role bile, sought identify mechanism, evaluated contributions T3SS translocated effectors vitro death. Our suggest cytotoxicity does not proceed by apoptotic or necrotic mechanisms, but rather displays characteristics consistent osmotic lysis. Cell was preceded disassembly junctions reorganization cortical membrane skeleton, although neither nor cell-cell disruption required VopM VopF, two known alter actin dynamics. Using deletion strains, we identified subset Vops are for death, which were previously assigned roles protein translocation colonization, suggesting they function other than promote cytotoxicity. The collective therefore cooperative Vop activities achieve vitro, alternatively, translocon pores destabilize dependent manner.