Preparation of anti-T idiotype monoclonal antibody reacting with human T leukaemic cell lines and with a small percentage of peripheral T lymphocytes.

Monoclonal antibody (MoAb) KT38 raised against a human T leukaemic cell line TALL-1, reacted with another T leukaemic cell line Jurkat, but not with any other cell lines tested. The co-modulation of CD3 and KT38 antigen was observed with stimulations of either MoAb T3 or KT38 on both TALL-1 and Jurkat. Upon radioimmunoprecipitation and SDS-PAGE analysis, MoAb KT38 precipitated the heterodimer of 40-60 kD from Jurkat and TALL-1 under reducing conditions. Thus, MoAb KT38 is considered to be an anti-T idiotype (Ti) antibody to TALL-1 and Jurkat cells. MoAb KT38 was also shown to react with a minor population of peripheral blood lymphocytes (PBL) and with very few cells (0.5-2.0%) in the paracortical area of the lymph node. When PBL were stimulated in a KT38-coated culture flask for 5 days, the percentage of KT38-positive PBL was markedly increased. The CD3 antigen on these cultured PBL in the flask was modulated by the stimulation with MoAb KT38. Thus, it is suggested that a common idiotope exists on the T cell receptor of Jurkat, TALL-1 and a small percentage (1.9-6.1%) of PBL.