A monoclonal antibody against altered LFA‐1 induces proliferation and lymphokine release of cloned T cells

Abstract

A murine monoclonal antibody (I‐17, IgM) has the following functional effects on murine long‐term T cell clones: inhibition of cell‐mediated lysis, induction of proliferation, release of lymphokines and change of the cell morphology. The determinant detected by I‐17 is expressed on long‐term T lines but not on thymocytes, lymph node cells and spleen cells. I‐17 precipitated proteins with apparent molecular mass of 220 kDa, 170 kDa, 150 kDa and 100 kDa. Biochemical studies indicate that the determinant recognized by I‐17 is tunicamycin sensitive and that I‐17 binds to the a chain of the lymphocyte function‐associated antigen (LFA‐1).