Proliferation potential of L3MBTL1-KD human hematopoietic progenitor cells. (A) The maintenance of CD34 expression was evaluated in L3MBTL1-KD CB cells by flow cytometry. GFP+CD34+ CB cells were cultured with SCF, FLT-3, IL-6, and TPO. *P < .005. (B) Cell counts of L3MBTL1-KD CB cells were monitored at different time points in liquid culture with SCF, FLT-3, IL-6, and TPO. (C) Seventy-two hours after lentiviral infection, sorted GFP+CD34+ HPCs were placed in CFU assays and the number of CFUs quantified. (D) p57 mRNA expression was assessed by quantitative RT-PCR in L3MBTL1-KD HPCs, with and without exposure to 200pM TGF-β1 for 2 hours (n = 2).