Lack of reactivity of sera from Theileria parva-infected and recovered cattle against cell membrane antigens of Theileria parva transformed cell lines.
Sera from Theileria parva infected, recovered and rechallenged cattle were tested in complement-dependent cytotoxicity, membrane immunofluorescence and antibody-dependent cellular cytotoxicity assays for the presence of antibodies against cell membrane antigens of T. parva transformed cell lines. In the complement-dependent antibody-mediated cytotoxicity assay, sera from lethally infected animals were negative. Some recovered cattle showed a positive reaction, but such reactions were also observed when an eland cell line infected with T. taurotragi, and bovine lymphoblastoid cells were used as targets. Reaction was less against Ig-negative peripheral blood lymphocytes. Evidence is presented that these reactions could be evoked by attachment of immune complexes to Fc-receptors. It is concluded that cattle exposed to T. parva infection do not develop antibodies against specific T. parva (or T. parva-induced) cell surface antigens.
D000818:Animals; D000920:Antibody-Dependent Cell Cytotoxicity; D000941:Antigens / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology*; D016782:Apicomplexa / Q000276:immunology*; D002417:Cattle; D002460:Cell Line; D003429:Cross Reactions; D003601:Cytotoxicity Tests, Immunologic; D005260:Female; D005455:Fluorescent Antibody Technique; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D051381:Rats; D011919:Rats, Inbred Strains; D013801:Theileriasis / Q000469:parasitology*
D000941:Antigens; D000954:Antigens, Surface