Protection of mice againstBabesiaspp. andplasmodiumspp. with killedCorynebacterium parvum

Abstract
Mice which had been pre-treated with killedCorynebacterium parvumgiven intravenously or intraperitoneally, but not subcutaneously, were completely resistant ot infection withBabesia microtiorB. rodhaini, and protected from death caused byPlasmodium vinckeiorP. chabaudiinfection. There is evidence that the parasites died within circulating erythrocytes. This occurred much too soon for a specific antibody response to be evoked, and no antibody could be detected by the indirect fluorescent-anitbody technique. Thus it is suggested that a non-secific soluble mediator may play an important role in the protection observed.