An enteroaggregative Escherichia coli strain of serotype O111 : H12 damages and invades cultured T84 cells and human colonic mucosa

The pathogenic mechanisms of enteroaggregative Escherichia coh (EAEC) are not well defined. We investigated the interaction of EAEC strain 236 (serotype O111:H12) with polarised Caco-2 and T84 human intestinal epithelia] cells lines, and,vith human jejunal and colonic mucosa. Strain 236 adhered to both polarised cell lines and to both intestinal tissue types, but caused severe damage and was invasive only in T84 cells and colonic mucosa. In contrast, prototype EAEC strain 042, which also adhered to the Cultured intestinal cell lines, did not adhere to or invade jejunal or colonic tissue. These observations suggest a heterogeneity of virulence properties within the EAEC category of diarrhoea-causing E. coli. (C) 2001 Federation of European Microbiological Societies. Published by Elsevier Science BN. All rights reserved.