Induction of apoptosis in HT29 human intestinal epithelial cells by the cytotoxic enterotoxin of Aeromonas hydrophila

• Published in: Biochemistry and cell biology Vol. 79; no. 4; pp. 525 - 531
• Main Authors: Falcón, R M, Carvalho, H F, Joazeiro, P P, Gatti, M S, Yano, T
• Format: Journal Article
• Language: English
• Published: Canada Canadian Science Publishing NRC Research Press 2001
• Subjects: Aeromonas hydrophila - metabolism; Aeromonas hydrophila - pathogenicity; Apoptosis; Apoptosis - drug effects; Bacteria; Bacterial Proteins; Cells; Cellular biology; Digestive system; Dose-Response Relationship, Drug; Enteritis; Enterotoxins - toxicity; Gastrointestinal diseases; HT29 Cells; Humans; Immune system; In Situ Nick-End Labeling; Infections; Intestinal Mucosa - microbiology; Intestinal Mucosa - pathology; Intestinal Mucosa - ultrastructure; Microscopy, Electron; Pathology; Toxins
• ISSN: 0829-8211; 1208-6002
• DOI: 10.1139/bcb-79-4-525

The cytotoxic enterotoxin produced by Aeromonas hydrophila is considered to be the main virulence factor in gastrointestinal infections mediated by this pathogen. In this study, we examined the morphological and apoptotic effects of this toxin on HT29 cells, using light and electron microscopy in situ, as well as agarose gel electrophoresis of cell DNA. Cells treated with the cytotoxic enterotoxin became round and lost their polarity as well as their adhesion to each other and to the substrate. Cytoplasmic blebbing and nuclear condensation also occurred. DNA fragmentation was detected by TUNEL labelling and agarose gel electrophoresis. These results show that the cytotoxic enterotoxin of A. hydrophila can induce apoptosis in human intestinal cells in culture.