title: The expression of Ia antigens on immunocompetent cells in the quinea pig. I the differential expression of Ia antigens on T cell subpopulations.
abstract: We have examined the effect of negative selection with anti-Ia serum and C on a number of T cell functions and have clearly defined two subpopulations of guinea pig T lymphocytes. One subpopulation is susceptible to the lytic effects on anti-Ia serum and C and includes the majority of the primed T cells which proliferate and which produce migration inhibition factor in response to specific antigen stimulation in vitro. The lytic effects of anti-Ia serum were directed against the antigen-specific T cell and not an accessory cell such as a macrophage or nonantigen-specific T cell. No evidence for allelic exclusion of the Ia antigens of the antigen-responsive cell could be demonstrated. The susceptibility of the mitogen-responsive T cell to lysis by anti-Ia serum and C varied with the mitogen used, anatomic origin of the T cell, and the strain of animals studied. A second subpopulation of T cells is completely resistant to the lytic effects of anti-Ia serum and C and includes the primed T helper cell and the T cell that proliferates in response to alloantigenic stimulation in the MLR.
mesh_terms: D000818:Animals; D000921:Antibody-Producing Cells; D003165:Complement System Proteins; D066298:In Vitro Techniques; D007518:Isoantibodies; D007519:Isoantigens; D008213:Lymphocyte Activation; D007959:Lymphocyte Culture Test, Mixed; D008263:Macrophage Migration-Inhibitory Factors / Q000096:biosynthesis; D008264:Macrophages / Q000276:immunology; D051379:Mice; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D007518:Isoantibodies; D007519:Isoantigens; D008263:Macrophage Migration-Inhibitory Factors; D003165:Complement System Proteins