Kinetic and Immunophenotypic Heterogeneity in Acute Myeloid Leukemia Subpopulations

Bone marrow samples of 27 cases of acute myeloid leukemia were studied by double staining with 3H-Thymidine and monoclonal antibodies (APAAP method). 3H autoradiography labels the nucleus of S-phase cells and immunocytochemistry (APAAP) detects cytoplasmic antigens. Different myeloid subsets were characterized with the monoclonal antibodies My7 (CD13), My9 (CD33), My4 (CD14), IOM11c (CD11c), Ber Mac3 and anti-HLA-DR. We have shown that there are different myeloid subsets with different proliferative patterns. The most notable finding was that in M4 acute leukemia only myeloid subsets were in the S-phase, while in M5 acute leukemia the highest percentage of proliferating cells was in the monocytic subsets.