Specific knockdown of Ledgf/p75 affects CFU activity of HSC. (A) qRT-PCR measuring Ledgf/p75 and Ledgf/p52 mRNA expression levels in lin⁻ cells harvested from 8-week-old C57BL/6J mice after transduction with lentiviral vector expressing a Ledgf/p75-specific miRNA (Ledgf/p75 KD) or eGFP-miRNA as a control. Expression levels were normalized to Gapdh. (B) CFU assay per 10⁴ cells after Ledgf/p75 knockdown. (C) HoxA9 expression levels (normalized to Gapdh) as measured by qRT-PCR in Ledgf/p75 knockdown cells. (D) qRT-PCR measuring Ledgf/p75 and Ledgf/p52 expression levels and serial plating of a myeloid CFU assay (E) after Ledgf/p52 knockdown (KD). Expression levels in panel D were normalized to Gapdh. (F) qRT-PCR measuring HoxA9 expression levels (normalized to Gapdh) in Ledgf/p52 knockdown cells after first plating in the CFU assay (E). (G) Peripheral WBCs measured after BM transplantation in lethally irradiated recipients transplanted with a total of 1 × 10⁶ lin− cells harvested from 8- to 10-week-old Psip^Fl/Fl and Psip^Vav/Vav mice. WBC was monitored 4, 8, 12, and 16 weeks posttransplantation. Mean values and SEM are indicated. Error bars (panels A-F) represent standard deviation of triplicate measurements. Differences in panels A-G were determined using Student t test; *P < .05, **P < .01, ***P < .001.