Nfix is required for the survival of HSPCs posttransplant . (A) CD45.1 LSK cells transduced with either control- or Nfix-shRNAs were transplanted into CD45.1/CD45.2 recipients and the marrow was harvested 10 days posttransplant. Cells were stained for lineage markers, Sca-1, c-Kit, Ki-67, and DAPI, and were analyzed via flow cytometry for cell cycle distribution in mCherry⁺ LSK cells. Data represent mean ± standard deviation from 1 experiment with five recipients in each group. (B) Flow analysis of cells harvested at the same time point as previously described and stained for lineage markers, Sca-1, c-Kit, annexin V, and DAPI for the analysis of apoptosis in mCherry⁺ WBM compartments. Data represent mean ± standard deviation from 3 independent experiments. P values were considered statistically significant when *P < .05, **P < .01, and ***P < .001.