Hinderance of apoptosis and phagocytic behaviour induced by Escherichia coli cytotoxic necrotizing factor 1: two related activities in epithelial cells.
Several microbial factors are recognized able to modulate apoptosis. In this work, we analyze the activity of a toxin from pathogenic strains of Escherichia coli, the Cytotoxic Necrotizing Factor 1 (CNF1), which influences epithelial cell structure and function. This toxin activates the Rho GTP-binding protein leading to actin filament reorganization, 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 corresponds to a decrease of apoptotic cell death. We therefore hypothesize that the two activities together might have a finalistic role in the pathogenesis of bacterial infection.
Fiorentini
C
C
Department of Ultrastructures, Istituto Superiore di Sanità, Rome, Italy. fiorentini@ul.net.iss.it
Fabbri
A
A
Matarrese
P
P
Falzano
L
L
Boquet
P
P
Malorni
W
W
D000199:Actins / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D001427:Bacterial Toxins / Q000494:pharmacology*; D048429:Cell Size / Q000187:drug effects; D003603:Cytotoxins / Q000494:pharmacology*; D004847:Epithelial Cells / Q000187:drug effects* / Q000528:radiation effects / Q000648:ultrastructure; D004926:Escherichia coli / Q000472:pathogenicity; D029968:Escherichia coli Proteins; D010587:Phagocytosis / Q000187:drug effects*; D014466:Ultraviolet Rays
D000199:Actins; D001427:Bacterial Toxins; D003603:Cytotoxins; D029968:Escherichia coli Proteins; C060296:cytotoxic necrotizing factor type 1