MAC (MORPHOLOGY, ANTIBODY, CHROMOSOMES) METHOD FOR STUDY OF CELL-PROLIFERATION IN UNFRACTIONATED HUMAN HEMATOPOIETIC-CELL CULTURES

The MAC (Morphology, Antibody, Chromosomes) method allows analysis of the karyotype of morphologically and immunologically classified interphase and mitotic cells. Its combination with harlequin staining procedures offers also a direct method for analyzing cellular kinetics. Our studies with mononuclear leukocyte cultures demonstrated that phytohemagglutinin (PHA) is as efficient as pokeweed mitogen (PWM) in inducing B cell proliferation when heterogeneous lymphocyte populations are used and that the combination of human heat-inactivated AB serum and interleukin-2 stimulates CD8 lymphocytes to proliferate almost exclusively. By combining MAC and the differential sister-chromatid staining procedure, we have also shown that human lymphocytes proliferate faster in cultures stimulated by PWM than in those stimulated by PHA. The MAC methodology, thus, appears very useful in studies of the effects of different growth factors and lymphokines on hematopoietic cells and in the recognition of neoplastic and non-neoplastic cells.