title: Antibody-mediated in-vivo cytotoxicity to Trichinella spiralis newborn larvae in immune rats.
abstract: The antibody-dependent cell-mediated larvicidal response of AO rats against Trichinella spiralis newborn larvae was studied in vivo. Rats were immunized with 2000-3000 muscle larvae orally and then challenged 6-20 days later with 10,000-20,000 newborn larvae intraperitoneally. Newborn larvae recovery from the peritoneal cavity decreased significantly and was accompanied by cuticular cell adherence and killing of newborn larvae by day 9 of infection. Similar effects were observed when newborn larvae were incubated with blood obtained from immunized rats. The cell adherence and larvicidal responses reached their peak by day 16 of the primary infection. Passive transfer experiments demonstrated that newborn larvae infectivity was substantially impaired once cell adherence occurred. Cuticular adherence took place in vitro only when immune serum was added to the incubation medium. Complete destruction of newborn larvae in vivo after passive transfer, as measured by muscle larvae burden was only evident after exposure to both immune serum and immune cells, not to either alone. Non-specific stimulation of the peritoneal cavity with a sterile intestinal infection failed to induce cuticular adherence or larval killing in these rats. We conclude that a stage-specific antibody-dependent cell-mediated larvicidal response is rapidly generated in vivo after the host is exposed to newborn larvae. It is a systemic response which impairs the infectivity of newborn larvae and can destroy them before they reach muscle tissue.
authors.affiliation: James A. Baker Institute for Animal Health, New York State College of Veterinary Medicine, Cornell University, Ithaca 14853.
authors.forename: C H
authors.initials: CH
authors.lastname: Wang
authors.forename: R G
authors.initials: RG
authors.lastname: Bell
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000920:Antibody-Dependent Cell Cytotoxicity; D002448:Cell Adhesion; D003429:Cross Reactions; D005260:Female; D007106:Immune Sera / Q000276:immunology; D007111:Immunity, Cellular; D007116:Immunization, Passive; D007411:Intestinal Diseases, Parasitic / Q000276:immunology*; D007700:Kinetics; D007814:Larva / Q000276:immunology; D008297:Male; D011897:Random Allocation; D051381:Rats; D014234:Trichinella / Q000276:immunology*; D014235:Trichinellosis / Q000276:immunology*
chemical_list: D007106:Immune Sera