Resistance to Taenia pisiformis larvae in rabbits: Immunization against infection using non-living antigens from in vitro culture

Abstract

Heath D. D. 1976. Resistance to Taenia pisiformis larvae in rabbits: Immunization against infection using non-living antigens from in vitro culture. International Journal for Parasitology 6: 19–24. A 97 % protection of rabbits against infection with Taenia pisiformis larvae was stimulated by subcutaneous injections of killed larvae cultured in vitro for 6 or 9 days, combined with the concentrated culture media in which the larvae grew. Larvae cultured in vitro for 3 days or less stimulated only 60% protective immunity. Exogenous antigens produced by 10-day old larvae in vitro were collected free of contaminating macromolecules, and were partially characterized. There appeared to be 6 exogenous antigens. Rabbits were immunized with either frozen larvae, or the exogenous complex, or both, using one subcutaneous injection of antigens adsorbed on aluminium phosphate. Exogenous antigens stimulated an 88% protection against challenge infection 14 days later, while only 52% protection was stimulated by somatic antigens from frozen larvae. The effects of the two antigen complexes were not additive. The protective ability of exogenous antigens was destroyed by exposure to air.