Single-cell transcriptomic landscape of human adult HSPCs across medullary and extramedullary hematopoietic tissues. Analysis of 10X Genomics scRNA-seq and CITE-seq data from 117 200 CD19^–CD34⁺ HSPCs isolated from BM, nonmobilized PB, and spleen of adult donors. (A) Uniform Manifold Approximation and Projection (UMAP) of the multisite HSPC landscape after exclusion of mature cells (see Methods). Clusters were annotated by using known lineage and stem cell marker genes found among the most differentially expressed genes in each cluster (supplemental Table 2a). Clusters with similar cell identity are shown as HSPC groups using different cluster colors. Detailed cluster composition is shown in supplemental Figure 1F, and HSCP grouping is summarized in supplemental Table 2c. (B-C) Three-dimensional plots (B) and violin plots (C) of lineage- and HSC-scores calculated for each cell by using published gene sets enriched in prospectively isolated HSPC subsets³⁹ (see Methods). (D) CITE-seq data from 2 BMs (OD3, 9 477 cells; OD4, 12 500 cells) and 1 spleen (OD4, 11 822 cells). UMAPs highlighting selected surface protein expression across the HSPC landscape. HSC/MPP, hematopoietic stem cell/multipotent progenitor; EryP, Ery progenitor; GMP, granulocyte-monocyte progenitor; LyP, lymphoid progenitor; MDP, monocyte/dendritic cell progenitor; MEMBP, megakaryocyte/erythroid/mast cell/basophil progenitor; MEP, megakaryocyte/erythroid progenitor; MyP, My progenitor; ND/LQ, cluster of lower quality which identity could not be defined using known marker genes; GMP, granulocyte-monocyte progenitor; MEP, megakaryocyte/erythroid progentitor; MLP, multilymphoid progenitor.