Modulation of T-cell antigen receptor on lymphocyte membrane.

A mouse monoclonal antibody, Mo. Ab. 108.45, detecting cell-surface determinants associated with the T-cell receptor for alloantigen was produced by immunizing mice with an alloreactive human T-cell clone and fusing the splenocytes with the NS1 plasmocytoma. This Mo. Ab. reacts with the immunizing T-cell clone but not with autologous or allogeneic lymphocytes, lymphoblasts or monocytes; stimulates the proliferation of the immunizing T cells in the absence of the alloantigen; inhibits the response to the specific stimulator; and precipitates a disulfied linked heterodimer composed of two distinct glycoproteins of molecular weights 40000 and 46000. The receptor molecule detected by Mo. Ab. 108.45 modulates on the surface of the cells, reaching the highest levels 5 days following exposure to the specific stimulator. The receptor-associated molecule detected by Mo. Ab. 108.45 was expressed by T-cell clones obtained independently in two different mixed lymphocyte cultures between the same responder and stimulator.