Fig. 1: Lack of embryonic myeloid cells results in decreased numbers of functional HSCs.

a Dot plots depict bone marrow cells of indicated mice at 3 weeks (18–32-day-old) of age resolved for the expression of indicated antigens. dapi-negative singlets were gated on lineage negative cells (Lin = CD3 CD19 NK1.1 Ter119 CD11b Gr1 B220) followed by Kit⁺ Sca1⁺ (KSL) gating. KSL cells were further subdivided into CD48^- CD150⁺ KSL SLAM cells. b Quantification of leukocytes (CD45), HSPCs (KSL), and HSCs (KSL Slam) as gated in a from mice of indicated genotypes in the bone marrow of 3-week-old mice (left). A two-sided unpaired Student’s t-test was used. (n = 51, 11 biological replicates for Rank^cre/+;Csf1r^fl/−, n = 72, 16 biological replicates for Csf1r^−/−, n = 37, 6 biological replicates for Vav^cre/+;Csf1r^fl/−). Fold-change comparisons between indicated populations in Rank^cre/+;Csf1r^fl/− mice compared to controls (right). Fold-changes were calculated by dividing the indicated cell types from Rank^cre/+;Csf1r^fl/− mice to the experimental average of the wildtype numbers For fold-change comparisons (right), a Mann–Whitney U test was performed to assess statistical significance between individual groups with an expected normal distribution. c Plot shows biological processes that are enriched in genes up-regulated in HSCs (KSL Slam) from Rank^cre/+;Csf1r^fl/− mice compared to wildtype controls (19–21-day-old). Over-representation analysis with a p-adjusted cutoff of 0.05 and subsequent semantic clustering was performed for 515 up-regulated genes using the gene ontology for biological processes from MSigDB. Colors indicate the p-adjusted value. A one-sided hypergeometric test was performed, with significance adjusted for multiple testing using the Benjamini-Hochberg method. d Plot depicts frequencies of KSL in the blood of 3-week-old (18–23-day-old-mice) Rank^cre/+;Csf1r^fl/− mice and controls. A two-sided unpaired Student’s t-test was conducted for statistical analysis. (n = 17, 3 biological replicates) e Fold-change of leukocytes (CD45), HSPCs (KSL), and HSCs (KSL Slam) from the spleen of 3-week-old Rank^cre/+;Csf1r^fl/− mice compared to wildtype mice is shown (left). A Mann–Whitney U test was performed for statistical analysis. (n = 14, 6 biological replicates) Colony formation from splenocyte suspension from indicated genotypes are depicted (right). A Mann–Whitney U test was performed. (n = 12, 2 biological replicates) f Plot shows donor cell contribution by HSPCs (KSL) from Rank^cre/+;Csf1r^fl/− mice and control donors (21–25-day-old) to blood neutrophils (PMN) at indicated time points after transplantation into non-conditioned recipient mice (Rag2^−/−;Il2rg^−/−;Kit^W41/W41, RgW41, modified from³⁴, left). A two-sided unpaired Student’s t-test was conducted for statistical analysis. (n = 24, 2 biological replicates). Donor cell contribution to HSCs (right). Each dot represents the value for one mouse in b, d-f. Source data are provided as a Source Data file.