Synergistic signal of an anti-hamster T cell monoclonal antibody on antigen-induced T cell proliferation.
1. The use of monoclonal antibodies (mAb) has permitted the identification of T cell surface antigens and the classification of these antigens based upon phenotype and function. Some of these monoclonal antibodies can identify antigens specifically involved in T lymphocyte activation and are also able to induce, under certain conditions, T cell proliferation. 2. We describe a new mAb raised against hamster T cells which binds to a 45-kDa cell surface antigen expressed on 45% of thymic cells and 90% of mature T lymphocytes. This mAb, designated X2VA, alone does not cause T cell proliferation, but increases in a synergistic manner T cell proliferation when these cells are cultured in the presence of specific antigens, or used in mixed lymphocyte reactions. 3. When the X2VA mAb is used as a single signal for the T cells it induces the production of a T cell growth factor, suggesting that the synergist effect observed during antigen-induced T cell proliferation is mediated by one or more cytokines. 4. Our results indicate that the X2VA mAb recognizes an antigen which is expressed during T cell ontogenesis and which is involved in hamster T cell activation.
Rodrigues-Júnior
V
V
Departamento de Parasitologia, Microbiologia e Immunologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brasil.
Fortes
F M
FM
Bongertz
V
V
Campos-Neto
A
A
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology*; D000954:Antigens, Surface / Q000302:isolation & purification*; D015153:Blotting, Western; D002450:Cell Communication; D006224:Cricetinae; D007376:Interleukin-2 / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D008213:Lymphocyte Activation / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000276:immunology*
D000911:Antibodies, Monoclonal; D000954:Antigens, Surface; D007376:Interleukin-2; D015847:Interleukin-4