Characterization of lymphocyte subpopulations in human cord blood using the immunogold staining technique

Lymphocyte subpopulations in human cord blood have been examined using monoclonal antibodies, visualized with immunogold. The proportions of T11, T4, T8, and B1 cells in cord blood are very similar to values in adult peripheral blood. Some evidence of lymphocyte immaturity in cord blood is suggested by the presence of 12% CALLA-positive cells and the sum of T4 and T8 cells significantly exceeding the number of T11 cells; however, there were no TdT-positive cells. The presence of CALLA-positive lymphocytes in normal cord blood should be borne in mind when investigating blood smears from neonates for congenital leukemia.