Figure 1.

Identification of 9 clusters of circulating monocytes by single-cell RNA sequencing of healthy peripheral blood HLA-DR+ cells. (A) Dot-plot showing annotated immune cells by lineage signatures (genes belonging to each signature are listed in Table S3 ). ssGSEA score-based signature expression is colored-coded from blue (lower) to yellow (higher); circle size indicates the fraction of cells expressing the signature. CD14⁺ mono, classical CD14⁺ monocytes; CD16⁺ mono, non-classical CD16⁺ monocytes; DCs, dendritic cells; NK cells, natural killer cells. (B) UMAP projection of CD45⁺Lin^-HLA-DR⁺ cells (n = 26,474) showing 20 clusters belonging to 5 major immune cell subsets. Clusters are numbered according to their size, from the largest (cluster 0) to the smallest (cluster 19). Each dot represents an individual cell. (C) Feature plots showing the expression of key genes adopted for manual annotation of myeloid cell clusters. Gene expression is colored-coded from gray (lower) to red (higher). (D) Dot-plot showing the expression of key genes adopted for manual annotation of clusters 10A and 10B. Gene expression is colored coded from gray (lower) to blue (higher); circle size indicates the fraction of cells expressing the gene.