Fig. 2

Characterization of hMSCs, hiPSCs, and hiPSC-RPE cells in vitro. A Expression of CD34 (a human hematopoietic progenitor marker, negative control) (i), CD44 (a hMSC marker) (ii), CD73 (a hMSC marker) (iii), and CD105 (a hMSC marker) (iv) on (a) hAFSCs, (b) hADSCs, (c) hDPSCs, and (d) hBMSCs using flow cytometry. B The expression of the human pluripotent stem cell markers Nanog (i), OCT4 (iv), and SSEA4 (vii) on hiPSCs with nuclear staining of DAPI (ii, v, viii), detected using immunofluorescence. (iii), (vi), and (ix) were generated by merging (I, ii), (iv, v) and (vii, viii), respectively. Scale bar: 20 μm. C The timeline of differentiation of hiPSCs into RPE cells. D0: Day 0; DM differentiation medium, NIC nicotinamide, CTM chetomin. D The differentiation of hiPSCs into RPE cells. Pigmented cells were observed by the naked eye on day 45 (i) and day 56 (ii). Pigmented cell pellets were observed on day 56 (iii). The morphology of hiPSC-RPE cells (iv). Scale bar: 50 μm. E The highly expression of the RPE-related markers MITF (i), PAX6 (ii), RPE65 (iii), and ZO-1 (iv) in hiPSC-RPE cells was analyzed using flow cytometry. F Expression of the RPE-related markers MITF (i), ZO-1 (iv), PAX6 (vii), and RPE65 (x) on hiPSC-RPE cells with nuclear staining of DAPI (ii, v, viii, xi), analyzed by immunofluorescence. (iii), (vi), (ix), and (xii) were generated by merging (i, ii), (iv, v), (vii, viii), and (x, xi), respectively. Scale bar: 20 μm. G Secretion of the trophic factors GDNF, TGF-β, BDNF, PEDF, VEGF, HGF, and FGF2 by hADSCs, hBMSCs, hAFSCs, hDPSCs, hiPSCs, and hiPSC-RPE cells, expressed as the amount secreted per million cells after two days of culture, as detected by enzyme-linked immunosorbent assay (ELISA). GDNF glial cell line-derived neurotrophic factor, TGFβ transforming growth factor-β, BDNF brain-derived neurotrophic factor, PEDF pigment epithelium-derived factor, VEGF vascular endothelial growth factor, HGF hepatocyte growth factor, FGF2 fibroblast growth factor 2, ND not detected. *p < 0.05