Animals were immunized with the cloned cytotoxic T lymphocyte lines V4 and 243/2.5; Spleen cells were fused with Sp2/0-Ag14 myeloma cells; L3T4 is expressed on mouse helper/induce T cells and is analogous to the human Leu-3/T4 molecule; The antibody profoundly blocks antigen specific murine class II MHC antigen reactive helper I lymphocyte lines; Tested and found negative for ectromelia virus （mousepox）Tumorigenecity： Isoenzyme： IgG2bHistopathology： hybridoma; Mouse（myeloma）Subculture： Split ratio： Media change： Reverse transcritase： Productionimmunoglobulin; Monoclonal antibody; Against mouse helper, inducer T cells （L3T4 antigen, CD4）.
