Homing and engraftment processes are independent of long-term residual damage induced by IR. (A) Schematic of the experiments. Wild-type (WT) and Ink4a/arf-deficient (KO) mice were sublethally irradiated (6 Gy) or not and injected 8 weeks later, before homing or engraftment were determined. (B) Representative flow cytometric profiles of hematopoietic cells found in the BM of flushed femurs 16 hours after BM transplantation or not of 5 × 10⁶ cells previously stained with CFSE. (C) Absolute number (average ± SEM) of CFSE⁺ cells present in femur whole BM (WBM) of WT or KO mice exposed (+) or not (−) to IR 8 weeks before being killed. n = 6-14 mice per group. (D) BM and peripheral blood (PB) engraftment 2 weeks after transplantation of 2 × 10⁶ CD45.1 unfractionated BM cells in WT or KO CD45.2 mice exposed (+) or not (−) to IR 8 weeks before transplantation. n = 4-5 mice per group. (E) Absolute number of donor-derived SLAM (Lin⁻, Sca-1⁺, c-Kit⁺, CD150⁺, CD48⁻) CD45.1⁺ in BM 2 weeks after transplantation in WT or KO CD45.2 mice exposed (+) or not (−) to IR 8 weeks before transplantation. n = 4-5 mice per group. *P < .05, **P < .01, and ***P < .001 by Student t test.