Re-Definition of Human T Cells by Monoclonal Antibodies

Analysis of sheep red cell (E) rosette forming human lymphocytes by indirect immunofluorescence shows that the majority 90%) stain with the monoclonal antibody UCHT1. E+UCHT1+ cells function as classical T cells. The remaining E+ cells (10%) are not active in T cell functional assays but do have high natural killer activity. Studies of patients with haemopoietic disorders or infectious mononucleosis using panels of monoclonal antibodies suggest that OKT1-like sera, previously considered to be markers for all peripheral T cells, identify heterogeneity within the suppressor/cytotoxic subset. Two major subsets differing in expression of OKT1-like antigen, Fc receptors for IgG and function have been identified.