Fig. 1

The hematopoietic supportive function of iPS-MSCs. a CD34⁺ cells were stained with CFSE and cultured with or without feeder cells for 5 days. Co-culture of HPCs with either MSCs or iPS-MSCs enhanced the number of cell divisions significantly (**P < 0.01; ***P < 0.001; n = 5—each with three biological replicates for MSCs and iPS-MSCs; MFI = mean fluorescence intensity). b Dot plots show CD34 expression in relation to the number of cell divisions (as a reference we used additional measurements at day 0; the number of cell divisions in different CFSE-gates is indicated). c We gated for specific cell division numbers and analyzed the signal intensity of CD34, CD133, CD45, and CD38 as compared to culture without feeder layer (gray). Co-culture with MSCs (red) or iPS-MSCs (blue) led to an increase of CD34 and CD133 expression and a decrease of CD45 expression in proliferating cells (without feeder vs. MSCs: *P < 0.05, **P < 0.01; without feeder vs. iPS-MSCs: ^# P < 0.05, ^## P < 0.01; MSCs vs. iPS-MSCs : ^§ P < 0.05; n = 5—each with three biological replicates for MSCs and iPS-MSCs). d CFU frequency was significantly increased by co-culture with either MSCs or iPS-MSCs (**P < 0.01, n = 3—each with three biological replicates for MSCs and iPS-MSCs). There was no significant bias for specific types of colonies. BFU-E = burst-forming-unit erythroid; CFU-E = colony-forming-unit erythroid; CFU-G = colony-forming-unit granulocyte; CFU-M = colony-forming-unit macrophage; CFU-GM = colony-forming-unit granulocyte, macrophage; CFU-GEMM = colony-forming-unit granulocyte, erythrocyte, macrophage, megakaryocyte. e Frequency of long-term culture initiating cells (LTC-IC) was significantly higher in co-culture with primary bone marrow-derived MSCs as compared to iPS-MSCs or without stromal support (*P < 0.05, **P < 0.01, ***P < 0.001, n = 3—each with three biological replicates for MSCs and iPS-MSCs). Mean ± S.D. is depicted