Thioglycolate medium decreases resistance to bacterial infection in mice

Brewer thioglycolate medium, a bacterial culture medium which is widely used as a nonspecific in vivo macrophage stimulant, was tested for its effect on mouse resistance to bacterial infection. Mice which did or did not receive thioglycolate medium were challenged with Listeria monocytogenes. Injection of thioglycolate medium significantly decreased the ability of the host to resist infection. This decreased resistance occurred whether thioglycolate medium was injected 0 to 9 days before, or 1 to 2 h after Listeria challenge. Bacteria grew considerably better in washed adherent peritoneal cells from thioglycolate medium-injected mice than in washed adherent peritoneal cells from normal mice. Thus, thioglycolate medium may ultimately cause a decrease in macrophage function.