Extended Data Fig. 7: Evi1extreme hi cells preferentially generate HSCs.
From: Independent origins of fetal liver haematopoietic stem and progenitor cells
a, Gene set enrichment analysis (GSEA) of an Evi1+ subset (Hlf+c-Kit+CD45− cells from caudal half region) compared with an Evi1lo/− subset (Hlf+c-Kit+CD45− cells from yolk sac) for HSC, MPP, and HSPC signatures. NES, normalized enrichment score; FDR, false discovery rate. b, Experimental design to trace the fate of Evi1extreme hi cells and Evi1hi cells within the same mouse (Evi1CreERT2ROSAtdTomato/YFP dual-reporter embryo). Given that the recombination rate of the ROSA26 locus is correlated with the expression level of Evi1 (Extended Data Fig. 6d), it can be inferred that tdTomato+YFP+ cells (recombination of two ROSA26 loci) originate from extreme Evi1 expressors. c, Lineage tracing of Evi1extreme hi (tdTomato+YFP+) and Evi1hi (tdTomato+YFP− or tdTomato−YFP+) cells. Evi1CreERT2ROSAtdTomato/YFP embryos were administered with tamoxifen at E10.5 and were analyzed at E14.5. Top, Representative flow cytometry plots of E14.5 Evi1CreERT2ROSAtdTomato/YFP fetal liver. Bottom, Comparison of cell labeling between tdTomato+YFP+ cells (Evi1extreme hi-derived) and tdTomato+YFP− or tdTomato−YFP+ cells (Evi1hi-derived). n = 7. d, Models and expected outputs of tracing experiments. In the standard model, label frequencies of progenitors would be similar to that of HSCs. In the HSC-independent model, label frequencies of progenitors would be significantly lower than that of HSCs. e, Number of Hlf+c-Kit+ cells in E10.5 (32–36 sp) HlftdTomato embryos (AGM, n = 3; yolk sac, n = 4). Number was calculated from flow cytometry data. f, Number of KSL (HSCs, ST-HSCs, MPPs) cells and KL (CMPs, GMPs, MEPs) cells in E14.5 fetal liver. n = 8. Number was calculated from flow cytometry data. g, Heterogeneity of Hlf+ hematopoietic clusters in the embryo. Whole-mount immunostaining analysis of E10.5 (32 sp) Evi1GFPHlftdTomato embryo for tdTomato (red), GFP (green) and CD31 (white). Scale bar, 50 μm. All error bars represent means ± SD. Statistical analysis was performed two-sided unpaired Student’s t-test (c).
