title: Studies of a human T lymphocyte antigen recognized by a monoclonal antibody.
abstract: A monoclonal antibody (designated L17F12) detects an antigen present on 95-100% of human peripheral T lymphocytes, the majority of thymocytes, and acute lymphocytic leukemia T cells but not B cells, B-cell lines, or monocytes. Examination of frozen tissue sections by the immunoperoxidase method revealed that the cells expressing this antigen were found predominantly in the medulla of thymus and in T-cell zones of lymph node and spleen. The antigen recognized by L17F12 was associated with a cell-surface glycoprotein of 67,000 daltons. L17F12 was used to isolate this molecule from human thymocytes, normal peripheral T cells, leukemic T cells, and T-cell lines. Expression of this antigen on normal T cells was not diminished by prolonged exposure in vitro to various T-cell stimuli. In the absence of complement, L17F12 bound to T cells without altering proliferative functions, thus enabling rapid purification of functionally intact T cells. In the presence of complement, L17F12 was cytolytic for T cells, providing the basis for depletion of T cells from heterogeneous populations. These data suggest that the monoclonal antibody L17F12 recognizes a specific T-cell differentiation protein. This antibody will be useful in studies of the human immune system.
mesh_terms: D000818:Animals; D000906:Antibodies; D000936:Antigen-Antibody Complex; D000941:Antigens / Q000032:analysis*; D001402:B-Lymphocytes / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007124:Immunoenzyme Techniques; D007945:Leukemia, Lymphoid / Q000276:immunology; D008198:Lymph Nodes / Q000276:immunology; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008970:Molecular Weight; D012397:Rosette Formation; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000906:Antibodies; D000936:Antigen-Antibody Complex; D000941:Antigens