Interaction between Clostridium difficile toxin A and mammalian cells
Chang, T.W.
Zhongguo Yao Li Xue Bao 4(3): 210-214
1983
ISSN/ISBN: 0253-9756 PMID: 6228124 Document Number: 215153
The interaction between C. difficile toxin A and human cells was studied using WI-38 ghosts. Adsorption to cultured cells was rapid during the first 10 min of exposure. There was a late increase in adsorption at higher temperatures. Toxin binding to RBC ghosts was temperature-dependent, higher at 37 than at 22 or O.degree. C. Adsorption to WI-38 cells and RBC ghosts was not influenced by pH changes ranging from 6.4 - 7.8. The release of bound toxin from WI-38 cells was minimal from intact cells, but greatly accelerated after the cells were fractured by repeated freezing and thawing. The release of toxin from RBC ghosts was not detected until 28 h after incubation, regardless of the incubation temperature. Only ghosts of human RBC bound toxin. RBC ghosts of rhesus monkeys, dogs, rabbits, sheep, rats, hamsters, guinea pigs, and chickens were inactive in toxin binding. Treatment with 2-mercaptoethanol or N-ethyl maleimide caused inactivation of toxin, suggesting that disulfide and SH bonds are essential for toxicity.