We describe the production of mouse monoclonal antibodies specific for the human TcR using as the immunogen transfected murine T-cell hybridoma cells coexpressing mouse CD3 with human Jurkat TcR alpha and beta chains. The shortage of monoclonal antibodies (mAbs) specific for the human TcR-V alpha and V beta families reflects the difficulties in their production by conventional methods using whole human T cells or purified soluble receptors as immunogens. As an alternative strategy to circumvent these difficulties, we have generated a transfected mouse T-cell line expressing a human (Jurkat) TcR alpha beta dimer in a complex with mouse CD3. The parental mouse T-cell line, TG40, is a cell surface TcR-negative, cytoplasmic CD3-positive variant of the mouse T-cell hybridoma 2B4. The human-TcR alpha beta expressing mouse transfectant was used to immunize mice with the same genetic background as the parent mouse T-cell line, and a human TcR-specific response was successfully achieved. MAb-producing hybridomas were generated by fusing spleen cells from the immunized mice with the mouse myeloma cell line NSO. Of 124 hybridoma supernatants screens, 72 showed reactivity to the human T-cell line Jurkat. Twenty-four of the hybridomas producing human (Jurkat) TcR-specific antibodies were cloned and screened for reactivity to Jurkat TcR. Several IgG2b and IgM mAbs specific for the Jurkat T cell line were selected on the basis of their ability to modulate surface CD3 expression on Jurkat cells. Most of the antibodies do not stain other TcR-expressing human T cell leukemia cell lines, implying specificity for the variable domains of the Jurkat TcR.(ABSTRACT TRUNCATED AT 250 WORDS)