Clostridium difficile Toxin B Induces Apoptosis in Intestinal Cultured Cells
AUTOR(ES)
Fiorentini, Carla
FONTE
American Society for Microbiology
RESUMO
Toxigenic strains of the anaerobic bacterium Clostridium difficile produce at least two large, single-chain protein exotoxins involved in the pathogenesis of antibiotic-associated diarrhea and colitis. Toxin A (CdA) is a cytotoxic enterotoxin, while toxin B (CdB) is a more potent cytotoxin lacking enterotoxic activity. This study dealt with CdB, providing the first evidence that intestinal cells exposed to this toxin exhibit typical features of apoptosis in that a significant proportion of the treated cells displayed nuclear fragmentation and chromatin condensation. In keeping with ultrastructural data, CdB-treated cells showed the typical flow cytometric hallmark of apoptosis consisting of a distinct sub-G1 peak. The CdB-induced apoptotic response was dose and time dependent and not simply due to the actin-disrupting effect of the toxin or to the subsequent impairment of cell anchorage. Rather, the inhibition of proteins belonging to the Rho family due to CdB seems to play a role in the induction of apoptosis in intestinal cells. The origin of cells and the growth rate may also be cofactors relevant to such a response.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=108253Documentos Relacionados
- Clostridium difficile Toxin B Induces Apoptosis in Intestinal Cultured Cells
- Clostridium difficile toxin A elicits Ca(2+)-independent cytotoxic effects in cultured normal rat intestinal crypt cells.
- Neutralizing Activity Against Clostridium difficile Toxin in the Supernatants of Cultured Colostral Cells
- Interaction of Clostridium difficile toxin A with cultured cells: cytoskeletal changes and nuclear polarization.
- Clostridium difficile toxin A perturbs cytoskeletal structure and tight junction permeability of cultured human intestinal epithelial monolayers.