HINDERANCE OF APOPTOSIS AND PHAGOCYTIC BEHAVIOR INDUCED BY ESCHERICHIA-COLI CYTOTOXIC NECROTIZING FACTOR-1 - 2 RELATED ACTIVITIES IN EPITHELIAL-CELLS

Several microbial factors are recognized able to modulate apoptosis. I n this work, we analyze the activity of a toxin from pathogenic strain s of Escherichia coli, the Cytotoxic Necrotizing Factor 1 (CNF1), whic h influences epithelial cell structure and function. This toxin activa tes the Rho GTP-binding protein leading to actin filament reorganizati on, membrane ruffling and multinucleation. Functionally, CNF1 induces a phagocytic activity in non-professional phagocytes. Surprisingly, we found that the increase of phagocytic activity induced by CNF1 corres ponds to a decrease of apoptotic cell death. We therefore hypothesize that the two activities together might have a finalistic role in the p athogenesis of bacterial infection. (C) 1997 Academic Press.