Single-cell map of peripheral blood across 6 patients with Sézary syndrome. (A) UMAP projection of the flow-sorted CD45⁺ immune cells (n = 54 994) across 6 patients: T cells/CTCL cells (Cluster 1, 2, 3, 4, 6, 7, 8, 9, 10, 12, and 15), myeloid cells (Cluster 5, 11, and 14), and B cells (Cluster 13). (B) Percent of cells expressing selected lineage markers for T cells (CD2 and CD3G), myeloid cells (ITGAM [CD11b] and ITGAX [CD11c]), and B cells (CD19 and CD79A). (C) Normalized correlation values across rows ranging from 0 to 1 for predicted immune cell phenotypes from the Human Primary Cell Atlas¹⁸ based on the SingleR R package¹⁷ for each cluster. (D) Percentage of total cells for each patient by cell type. (E) Cell distribution by patient sample both as contour graphs and summarized in the accompanying bar chart by patient and cluster. Clusters representing >15% of total patient cells are labeled.