ENDOTOXIN-INDUCED TOLERANCE TO TOXIC MANIFESTATIONS OFCANDIDA ALBICANS

Abstract

Mice exposed to 425 r total body irradiation failed to become tolerant to Candida albicans toxicity after injection with lipopolysaccharide. Mice injected with lipoplysaccharide and then X- rayed did not demonstrate the tolerant state. An injection of thorium dioxide in mice that had previously received tolerance inducing amounts of lipopolysaccharide rendered them as susceptible to acute C. albicans toxicity as control mice. A bimodal manifestation of tolerance was noted. Groups of mice given single injections of lipopolysaccharide at 6 or 1 days before challenge demonstrated high levels of tolerance, whereas the tolerance in mice given a single dose at 3 days was negligible. The bimodal effect was not observed in tolerant mice challenged with lipopolysaccharide. Injections of viable or nonviable pathogenic fungi known to produce tolerance to the toxicity of C. albicans in recipient mice did not produce tolerance to lipopolysaccharide. Serum from mice injected with lipopolysaccharide showed in vitro inhibitory activity for C. albicans.