Both Fc receptors and lymphocyte‐function‐associated antigen 1 on human Tγ lymphocytes are required for antibody‐dependent cellular cytotoxicity (killer cell activity)

摘要

AbstractA monoclonal antibody, designated CLB‐LFA‐1/1, directed to the human lymphocyte‐function‐associated antigen 1 (LFA‐1) was raised by immunization of mice with the peripheral blood lymphocytes of a Tγ lymphocytosis patient. The monoclonal antibody was selected by inhibition of the natural killer cell and the antibody‐dependent killer cell activity of the patient's Tγ lymphocytes. In addition, the monoclonal antibody was shown to inhibit the cytotoxic activity of T cell clones specific for either class I or class II HLA molecules. The antigen recognized by CLB‐LFA‐1/1 consisted of three polypeptide chains with molecular weights of 180000 (α), 155000 and 94000 (β). The antibody reacted with T cells, B cells, monocytes and granulocytes, and stained normal Tγ cells and Tγ cells of patients with Tγ lymphocytosis two‐ to threefold stronger than normal T cells. It was shown that LFA‐1 and the Fc receptor on Tγ cells did not comodulate and it is therefore concluded that Fc receptors and LFA‐1 are independent membrane structures, both required for the kil