Ex vivo expansion and colony-forming potential of peripheral blood CD34⁺ cells after treatment with TAT-NF-Ya. Human peripheral blood CD34⁺ cells were treated with TAT-NF-Ya (or not treated) for 1.5 hours and then cultured for 30 days in serum-free media supplemented with Flt-3/Flk-2L, SCF, thrombopoietin (100 ng/mL each), and IL-3 and IL-6 (20 ng/mL each). Total mononuclear cells (A) were counted; the number of colony-forming erythroid (ER indicates BFU-E), CFU-GM, and CFU-GEMM were measured by methylcellulose assays (B), and the relative contribution to the progenitor cell pool of each class of progenitors calculated (C).