Selective in-vitro activation of BALB/c T suppressor lymphocytes specific for syngeneic ADJ-PC-5 plasmacytoma cells

T suppressor (Ts) lymphocyte activation is the first reaction of the immune system under conditions which simulate early stages of tumourigenesis. There is evidence that the Ts cell inducing antigen on ADJ-PC-5 plasmacytoma cells of BALB/c origin is a self antigen, which is also expressed on normal BALB/c spleen cells. In order to study this Ts cell inducing determinant in more detail we have developed an in vitro system which allows the selective activation of ADJ-PC-5 specific Ts cells in the absence of activation of cytotoxic T (Tc) cells. The system now allows us to study the modulation of Ts cell induction and function.