Conditional deletion of Cited2 results in decreased numbers of LT-HSCs. (A) pI-pC treatment induces efficient deletion of Cited2, as determined by relative expression of Cited2 mRNA normalized to 18S RNA in LSK cells (mean ± SEM, n = 8). (B-D) Approximately 2-3 weeks after pI-pC treatment, no significant difference was found between wild-type (WT) and Cited2^Δ/Δ mice in WBC number (B), BM cellularity (C), and LSK cell number (D). Data shown are means ± SEM (n = 6). (E) Flow cytometric analysis shows that, compared with wild-type controls (top panel), Cited2^Δ/Δ LSK cells (bottom panel) display a significantly decreased Flt3⁻CD34⁻ or CD48⁻CD150⁺ fraction, which corresponds to LT-HSCs. WT and mutant mice were from the same litter and experiments were performed independently at least twice. The numbers in the Lin⁻-gated plots indicate the percentage of total BM mononuclear cells, whereas the numbers in the LSK-gated plots indicate the percentage within the gated population. (F) The percentage of LT-HSCs (CD48⁻CD150⁺ or Flt3⁻CD34⁻), short-term HSCs (Flt3⁻CD34⁺), and multipotent progenitors (Flt3⁺CD34⁺) in LSK cells are shown as means ± SEM (n = 4).