HLA-DR antigens and mitogenic factors released by PWM-stimulated T lymphocytes share the framework determinant recognized by the monoclonal antibody Q5/13

Human T lymphocytes release factors which enhance the mitogenic response of B lymphocytes to PWM. These mitogenic factors share with HLA-DR antigens the framework determinant recognized by the monoclonal antibody Q5/13 (MoAb Q5/13) since adsorption of T-cell medium with an excess of insolubilized MoAb Q5/13 significantly reduces the enhancing activity of the T-cell supernatant on the proliferative response of B cells to PWM. On the other hand, incubation of the T-cell supernatant with an excess of insolubilized anti-HLA-A,B MoAb Q1/28 did not effect the activity of the T-cell supernatant in the proliferative assay.