title: Accessory molecules in T lymphocyte activation.
abstract: The currently accepted hypothesis used to explain the role of Lyt-2 and L3T4 in T cell activation proposes how these molecules interact with class I and II major histocompatibility complex molecules, respectively, on the antigen-presenting or target cell, to increase the avidity of binding of the antigen-specific T cell receptor. This has been tested using two antigen-specific, class II-restricted T cell clones expressing both Lyt- and L3T4. Inhibition of function was observed only with monoclonal antibody against L3T4, not Lyt-2. One interpretation of these results is that L3T4 and the class II-restricted T cell receptor can physically associate during T cell activation to form a multi-molecular complex from which Lyt-2 is excluded.
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000938:Antigen-Presenting Cells / Q000276:immunology; D000941:Antigens / Q000378:metabolism; D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology*; D006801:Humans; D008213:Lymphocyte Activation; D051379:Mice; D008954:Models, Biological; D011485:Protein Binding; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000941:Antigens; D000945:Antigens, Differentiation, T-Lymphocyte; D000950:Antigens, Ly; D000954:Antigens, Surface; D011948:Receptors, Antigen, T-Cell