The landscape of developmental arrest states across acute leukemia subtypes. (A) Patient cohort across leukemia subtypes. (B-C) Overall UMAPs of all scRNA-seq cells (B) and scATAC-seq cells (C) from 96 leukemia samples, colored by major cell types. (D) Bubble plot of manually curated marker genes for leukemic blasts and healthy cells. Color represents scRNA-seq z score. Bubble size represents the percentage of cells expressing a marker in a given population. (E) UMAPs of healthy human hematopoiesis based on scRNA-seq (left) and scATAC-seq (right) data from healthy donor (HD) samples of pediatric bone marrow¹³ and thymus.¹⁴ Cell type annotation for scATAC-seq data was label-transferred from scRNA-seq data. (F) Fractions of leukemic blasts projected onto stem/progenitor, T-lineage, B-lineage, and myeloid-lineage trajectories using healthy reference data. Clinical information of each patient is shown at the bottom. B-M, B-myeloid; CLP, common lymphoid progenitor; DP, double positive T cells; GMP, granulocyte monocyte progenitor; iB-ALL, infant B-ALL; LMPP, lympho-myeloid primed progenitor; MEP, megakaryocyte erythroid progenitor; MPP, multipotent progenitor; pB-ALL, pediatric B-ALL; pDC, plasmacytoid dendritic cells; T-M, T-myeloid; T/NK, T/natural killer cells; UMAP, Uniform Manifold Approximation and Projection.