Participation of suppressor T cells in the immunosuppressive activity of a heteroantiserum to human Ia-like antigens (p23,30)

We studied the effects of an antiserum to human Ia-like antigens (p23,30) upon the polyclonal activation of normal B cells (cultured with various combination of irradiated and unirradiated T cells) to become immunoglobulin-secreting cells after stimulation with pokeweed mitogen in vitro. We found that the antiserum suppressed immunoglobulin production. The inhibitory effect did not appear to result from a simple interaction at the B-cell/monocyte level alone. Rather, the inhibitory effect required the presence of a radiosensitive subset of autologous suppressor T cells.