Effects of Corynebacterium parvum on Escherichia coli Infection in Mice

Publisher Website
Google Scholar
Abstract
The contribution of activated macrophages to protection against E. coli was studied in mice. Mice treated i.p. with killed C. parvum 1 day prior to challenge showed an increased resistance to i.p. infection with E. coli; the predominant leukocytes in the peritoneal cavity of these animals were polymorphonuclear cells. Treatment with C. parvum 4 day prior to challenge induced mainly activated macrophages in the peritoneal cavity; host resistance to the infection was not increased. Activated macrophages from such mice showed both enhanced phagocytic activity in vivo and a high degree of intracellular killing of E. coli in vitro. These cells became more susceptible to the cytotoxic effect of endotoxin. After challenge with E. coli there was a marked decrease in the number of peritoneal macrophages in mice that were treated with C. parvum 4 day prior to challenge. Increased susceptibility of activated macrophages to the cytotoxic effect of endotoxin could explain the absence of enhanced resistance to E. coli infection in such animals.

This publication has 2 references indexed in Scilit: