Association of adherence and motility in interleukin 8 induction in human intestinal epithelial cells by Vibrio cholerae.
Interleukin 8 (IL-8) mRNA expression in Vibrio cholerae-infected human intestinal epithelial cells Int407 was determined by quantitative real-time RT-PCR and secretion measured by ELISA. Incubation of Int407 with V. cholerae O395 resulted in increased IL-8 mRNA expression as early as within 2 h of infection. Kinetics of IL-8 secretion reached a peak at about 8 h (780 pg/ml) and decreased thereafter. Induction of IL-8 was significantly high among various toxin-producing strains of V. cholerae belonging to serovar O1, O139 and non-O1 compared to non-toxinogenic strains. Induction of IL-8 was maximum in V. cholerae O395, required live cells and was dependent on de novo protein synthesis. The bacterial culture supernatant and crude cell envelope showed IL-8 stimulating activity. Infection of the monolayer with V. cholerae O395 cheY4 null mutant (O395YN), defective in adherence and motility, resulted in highly reduced levels of IL-8 expression, while hyperadherent and hypermotile mutant (O395Y) with the cheY4 gene duplicated also showed very high IL-8 expression. Another hyperadherent icmF insertion mutant (O395F) with reduced motility showed almost half the amount of IL-8 expression compared to O395Y. These results clearly indicate that both motility and adherence to intestinal epithelial cells are possible triggering factors contributing to IL-8 mRNA expression by V. cholerae.
Sarkar
Madhubanti
M
Human Genetics & Genomics Group, Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Calcutta 700032, India.
Chaudhuri
Keya
K
D001422:Bacterial Adhesion; D002460:Cell Line; D004847:Epithelial Cells / Q000382:microbiology; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D007413:Intestinal Mucosa / Q000166:cytology / Q000276:immunology / Q000382:microbiology; D009068:Movement; D014734:Vibrio cholerae / Q000276:immunology / Q000472:pathogenicity* / Q000502:physiology
D016209:Interleukin-8