Functional and biochemical characterizations of avian T lymphocyte antigens identified by monoclonal antibodies.
Seven monoclonal antibodies (mAb) were used to characterize antigens present on chicken T lymphocytes and on natural killer cells by flow cytometry, radioimmunoprecipitation and by effects on cell-mediated cytotoxicity and mitogen-induced proliferation. mAb CTLA8 and 5 stained 73% of thymus, 44% of spleen and 51% of peripheral blood lymphocytes (PBL), respectively, and immunoprecipitated 65- and 45-kDa proteins from detergent extracts of 125I surface-labeled thymocytes. Pretreatment of splenic lymphocytes with mAb CTLA5 and 8 in the presence of rabbit complement (C) eliminated the concanavalin A (Con A)-induced T cell proliferative responses. mAb CTLA3, 4 and 9 stained 43% of thymus, 36% of spleen and 18% of PBL, and immunoprecipitated 33-35-kDa proteins. Pretreatment of spleen cells with mAb 4 or 9 plus C reduced, but did not eliminate, the Con A-induced proliferative response and significantly reduced both major histocompatibility complex (MHC)-restricted and non-MHC-restricted cellular cytotoxicity. mAb CTLA1 and 6 stained 58% of thymus, 13% of spleen and 19% of PBL. mAb CTLA1 and 6 immunoprecipitated a 65-kDa protein. mAb CTLA1 and 6 had no effect on the Con A-induced blastogenesis and CTLA6 caused no decrease in virus-specific cytotoxic T lymphocyte and natural killer activity. These results indicate that (a) mAb CTLA5 and 8 identify antigens on mature T lymphocytes that are similar in tissue distribution, molecular mass and function to the mammalian CD5 antigen; (b) mAb CTLA3, 4 and 9 detect the avian homologue of CD8 antigen; and (c) mAb CTLA1 and 6 identify the avian homologue of CD4 antigen.
Lillehoj
H S
HS
Protozoan Diseases Laboratory, U.S. Department of Agriculture-ARS, Beltsville, MD 20705.
Lillehoj
E P
EP
Weinstock
D
D
Schat
K A
KA
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000945:Antigens, Differentiation, T-Lymphocyte / Q000276:immunology*; D002460:Cell Line; D002645:Chickens / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D005434:Flow Cytometry; D007113:Immunity, Innate; D007694:Killer Cells, Natural / Q000276:immunology; D008213:Lymphocyte Activation; D008970:Molecular Weight; D013601:T-Lymphocytes / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000945:Antigens, Differentiation, T-Lymphocyte