Capacity of Monocytes from Patients with Chronic Myelomonocytic Leukemia to Differentiate into Macrophages and Multinucleated Giant Cells

Monocytes from patients with chronic myelomonocytic leukemia (CMML-Mo) strongly expressed CD14 and CD2, but not CD16. Macrophages (MΦ) generated from CMML-Mo expressed CD32, but not CD16. The expression levels of CD64 were significantly reduced from normal MΦ. While CMML-Mo-derived MΦ phagocytosed sensitized SRBC, these cells exhibited a similar defect as CMML-Mo in the ability to produce O2-. CMML-Mo could generate dendritic cells (DC), but not multinucleated giant cells (MGC), suggesting that CMML-Mo are different from normal Mo in cell surface marker expression, O2- production, and the ability to differentiate into MΦ and MGC, but not DC.