The effect of miR-17 modulation in FBMOB-hTERT cells on CB CD34⁺ cells.

A: The effect of miR-17 modulation in FBMOB-hTERT cells on long-term culture initiating cells activity of CB CD34⁺ cells. 1.0×10⁴ CD34⁺ CB cells were co-cultured with FBMOB-hTERT cells after transduced with vectors for miR-17 overexpression (17/OE), miR-17 knockdown (17/KD), or control (CTRL) for 5-8 weeks and then subject to colony-forming-unit (CFU) assay. After 14-16 days of culture, the colonies, including CFU-Mixs, CFU-E, and BFU-E with greater than 50 cells were counted. The results are expressed as mean ± SD (n = 6). *p<0.05, compared between 17/OE or 17/KD, and CTRL group (Student’s t-test). B: Effect of miR-17 modulation in FBMOB-hTERT cells on repopulation of CB CD34⁺ cells in non-obese diabetic/severe combined immunodeficient disease (NOD/SCID) mice. 5.0×10⁴ CB CD34⁺ cells were co-cultured with 17/OE, 17/KD or CTRL, harvested at 4 weeks of culture and then injected intravenously into the sublethally irradiated NOD/SCID mice (n = 6 per group). The mice were sacrificed 12 weeks after transplantation and the mononuclear cells from bone marrow were analyzed for human cells composed of CD45⁺, CD45^–CD36⁺ and CD36^–GPA⁺ cells and CD45⁺CD34⁺ population by flow cytometry. The level of total human cell engraftment was shown in the left panel. P = 0.031 or 0.046, compared between the NOD/SCID mice injected with CD34⁺ cells co-cultured with 17/OE or 17/KD and those injected with CD34⁺ cells co-cultured with CTRL (Student’s t-test). The fraction of CD45⁺, erythroid (CD45⁻CD36⁺ and CD36⁻GPA⁺) and CD45⁺CD34⁺ population among the engrafted human cells was shown in right panel. *p<0.05, compared between the NOD/SCID mice injected with CD34⁺ cells co-cultured with 17/OE and those injected with CD34⁺ cells co-cultured with CTRL (Student’s t-test). The significant difference was only analyzed between the mice injected with CD34⁺ cells co-cultured with 17/OE or 17/KD and those injected with CD34⁺ cells co-cultured with CTRL.