Proliferative dynamics, DNA damage and transcriptional programs of human HSPCs in low-cell dose transplantation assay. (A) Composition of human BM HSPCs compartment in low-, middle-, and high-engrafted mice at both 6 and 20 wk after transplantation. (B and C) Correlation between the percentage of total proliferating HSPCs (BrdU⁺EdU⁻; BrdU⁺EdU⁺; BrdU⁻EdU⁺) with human engraftment in murine BM at 6 and 20 wk after transplantation. Statistical test: Spearman r; 6 wk, P = 0.041; 20 wk, P = 0.0115. (D) Correlation between the percentage of T cells that entered S phase per hour (BrdU⁺EdU⁻) with human engraftment in PB at 20 wk after transplantation. Statistical test: Spearman r; P = 0.0002. (E–G) Relative mRNA expression of inflammatory genes IL1α, MCP1, and TNFα in human CD34⁺ cells isolated from low- and high-engrafted mice at 20 wk. Statistical test: Mann–Whitney; IL1α, P = 0.051; MCP1, P = 0.0571; and TNFα, P = 0.0571. (H and I) Representative images and Olive Tail Moment average values of neutral (H) or alkaline (I) comet assays conducted on CD34⁺ isolated from low- or high-engrafted mice at 20 wk after transplantation. White lines indicate the length of 100 µm. Statistical test: Mann–Whitney; alkaline: L vs. H, P = 0.0159. (J) Correlation between the frequency of pRPA⁺ cells within HSPCs with human engraftment in murine BM at 20 wk after transplantation. Statistical test: Spearman r; P = 0.0003. (K) List of top 20 TFs associated to enriched binding sites unique for high-engrafted (open in high) and low-engrafted (open in low) mice. Each TF is colored according to its biological function in HSCs. * < 0.05.