CMML patients accumulate abnormal MO1s at the expense of MO3s. (A) Lack of significant correlation between the percentage of MO1s and peripheral blood monocyte count in reactive monocytosis (black circles) and in CMML (red circles). Reactive monocytoses and CMML samples from the learning and validation cohorts were pooled. (B) Absolute number of MO1s and MO3s in the peripheral blood of CMML patients as compared to age-matched healthy donors (Aged-Co), non-CMML patients, and patients with reactive monocytosis. The learning and validation cohorts were pooled (***P < .0001; Student t test). (C) Component principal analysis of gene expression after RNA sequencing (DESSeq2 analysis) in MO1s sorted from the blood of healthy donors (green) and patients with reactive monocytosis (blue) or CMML (red). (D) Heatmap established by using Cytobank software to summarize the flow cytometry analysis of 8 markers at the surface of MO1s from 6 age-matched healthy donors and 17 CMML patients.