Anti-T-cell idiotype activity in serum of mice injected with syngeneic hapten-specific T-cell lines.

T cells able to mediate specific delayed type hypersensitivity (DH) in mice in response to the haptens azobenzenearsonate (ABA), oxazolone (OX), and picryl chloride have been grown in continuous cultures. They were tested for their ability to react with the hapten in vitro and to induce anti-idiotype antibody in syngeneic mice. Incubation in vitro with OX-glycine blocked the ability of an anti-OX cell line to produce DH in vivo but had no effect on an anti-ABA cell line. However, this was inhibited by ABA conjugated to bovine serum albumin (ABA-alb) but not by irrelevant haptens such as OX-glycine or trinitrophenyl-alb. Antisera prepared by immunizing syngeneic mice with the anti-OX line blocked the inhibitory effect of OX-glycine on that line but did not reverse the effect of ABA-alb on the anti-ABA line. Neither normal mouse serum nor inappropriate anti-line antisera could influence the effect of OX-glycine on the anti-OX line. When given alone to naive mice, a specific anti-line antiserum induced DH specific for the antigen to which the line was responsive. Thus, for example, antiserum directed to an anti-OX line produced OX-specific DH. The results suggest that anti-T-cell idiotype antibodies can be induced by immunizing mice with syngeneic antigen-specific T-cell lines and that these antibodies can block the specific in vitro interaction of antigen with the corresponding antigen-specific T cells and induce specific DH in vivo.