Monoclonal Antibodies Defining Distinctive Human T Cell Surface Antigens

Three novel monoclonal antibodies (designated OKT1, OKT3, and OKT4) were generated against surface determinants of human peripheral T cells. Both OKT1 and OKT3 reacted with all human peripheral T cells and 5 to 10 percent of thymocytes but differed in their reactivities with T cell lines. By contrast, OKT4 reacted with 55 percent of human peripheral T cells and 80 percent of thymocytes. All three antibodies were selective for T cells in the peripheral blood in that they did not react with normal B cells, null cells, monocytes, or granulocytes.