title: Mechanisms controlling TCGF production by cloned sublines of EL-4 azgr in response to stimulation by anti-Thy-1 antibody.
abstract: The effect of xenogeneic anti-Thy-1 antibody on T cell growth factor (TCGF) production by T lymphoma cell lines has been examined as a model system for T cell activation. EL-4 G12 (a cloned subline of the producer EL-4 azgr cell line) produced TCGF when stimulated by a high concentration of anti-Thy-1, but none was induced by low concentrations of anti-Thy-1. Large amounts of TCGF were produced when these cells were cultured with Fc-receptor positive (FcR+) accessory cells. TCGF production by EL-4 G12 showed dose response kinetics similar to TCGF production by anti-Thy-1-stimulated, purified normal spleen T cells. Goat anti-rabbit IgG (GaRIG) and protein A substituted for this accessory helper effect, but neither FcR+ cells nor Protein A worked when (Fab')2 anti-Thy-1 was used instead of IgG anti-Thy-1. Anti-T-200 monoclonal antibody inhibited anti-Thy-1-induced TCGF production by EL-4 G12 and accessory cells. Phorbol myristic acetate and lymphocyte-activating factor also substituted in part for the accessory cell help. The data suggest there are at least 2 different accessory cell help mechanisms in anti-Thy-1-induced TCGF production, anti-Thy-1-bound membrane aggregation either by GaRIG, Protein A or FcR, and a LAF-dependent mechanism.
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology*; D000954:Antigens, Surface / Q000276:immunology*; D002460:Cell Line; D002999:Clone Cells / Q000276:immunology; D006023:Glycoproteins / Q000276:immunology; D007376:Interleukin-2 / Q000096:biosynthesis*; D008222:Lymphokines / Q000096:biosynthesis*; D008223:Lymphoma / Q000276:immunology*; D008565:Membrane Proteins / Q000276:immunology*; D011817:Rabbits; D011961:Receptors, Fc / Q000276:immunology; D012995:Solubility; D013601:T-Lymphocytes / Q000276:immunology; D018800:Thy-1 Antigens
chemical_list: D000906:Antibodies; D000954:Antigens, Surface; D006023:Glycoproteins; D007376:Interleukin-2; D008222:Lymphokines; D008565:Membrane Proteins; D011961:Receptors, Fc; D018800:Thy-1 Antigens