Fig. 4

Co-culture with MSCs or iPSC-derived MSCs supports growth of iPSC-derived HPCs. a Schematic representation of co-culture experiments of iHPCs with syngenic MSCs and iMSCs (donors 1–3). b Phase contrast images of iHPCs upon expansion for 2 weeks on tissue culture plastic (TCP), MSCs, and iMSCs. Scale bar 100 μm. c Proliferation of iHPCs on TCP, MSCs, or iMSCs was estimated by residual CFSE stain after 5 days. The mean fluorescence intensities (MFI) were normalized to corresponding measurements at d0. Data represent the mean of three independent experiments ± SD (ANOVA was not significant). d Colony-forming unit (CFU) frequency of iHPCs at day 20 and after 14 days of co-culture expansion on TCP, MSCs, or iMSCs. Data represent mean of three independent experiments ± SD; ANOVA: **P < 0.01; ***P < 0.001. e Flow cytometry analysis of iHPCs on day 14 of co-culture as depicted in a. f Quantitative analysis of flow cytometric measurements. GlyA: glycophorin A. g Cytospins of iHPCs at day 34. Morphologies relate to hematopoietic progenitor cells (1), macrophages (2), monocytes (3), and neutrophils (4). Scale bar 20 μm