Sensitivity to injected (exogenous) antigens was determined at various intervals after primary and challenging infections with Trichinella spiralis. Infected mice showed marked reactions (including congestion of the small intestine) after intravenous injections of homologous but not heterologous antigens. Sensitivity to specific antigen was demonstrated before the immune elimination of intestinal worms (from both primary and challenging infections) began and reached its peak after most of these adult worms had been eliminated. Injections of cortisone inhibited both immunity to infection and reactivity to exogenous antigen.
Host sensitivity to exogenous antigens has been associated with the interval of immune elimination of intestinal worms. It is suggested that some of the intestinal pathology associated with worm elimination may represent host allergic responses to endogenous worm antigens, antigens naturally released during the course of infection.
Present address: Department of Medical Zoology, Walter Reed Army Institute of Research, Walter Reed Army Medical Center, Washington, D. C. 20012.
This work was supported in part by Research Grant AI-05304 from the National Institutes of Health, U. S. Public Health Service. A contribution from the Laboratory of Parasitology, Department of Biology, Wayne State University.