Antigenic Expression and Proliferative Status of Multilineage Myeloid Progenitor Cells (CFU‐GEMM) in Normal Individuals and Patients with Chronic Granulocytic Leukaemia

Abstract

The number of multilineage myeloid progenitor cells (CFU-GEMM) was assayed in the blood and marrow of patients with newly diagnosed chronic granulocytic leukemia (CGL). The mean number of CFU-GEMM in the blood was increased 600-fold and CFU-GEMM in the marrow was doubled in the CGL patients compared with normal. A complement-fixing monoclonal antibody with HLA-DR specificity inhibited the proliferation of CFU-GEMM from CGL blood to a greater extent than that of comparable cells in normal marrow. Using a hydroxyurea suicide method the proportion of CFU-GEMM in proliferative cycle was found to be higher in CGL blood than in normal marrow. CFU-GEMM numbers are greatly increased in the blood of patients with CGL, CFU-GEMM express HLA-DR antigens on their surface, and the apparently increased expression of the antigen on CFU-GEMM from CGL blood in comparison with CFU-GEMM from normal marrow may parallel the relatively higher proportion of CGL CFU-GEMM in cell cycle.