Hepatic differentiation of rat induced pluripotent stem cells in vitro

Figure 1 Morphological changes of rat induced pluripotent stem cells at different stages of differentiation. A: Undifferentiated induced pluripotent stem cells; B: Differentiated cells on day 5; C: Differentiated cells on day 15; D: Differentiated cells on day 20. Scale bar = 100 μm.

Figure 2 Protein expression in differentiated induced pluripotent stem cells on days 5 and 20 as indicated by immunofluorescence staining. A, B, C: FOXA2; D, E, F: SOX17; G, H, I: AFP; J, K, L: ALB; M, N, O: CYP1A2; P, Q, R: CYP3A4; S, T, U: AAT; V, W, X: CK18. Nuclei were stained blue with DAPI. Scale bar = 100 μm. FOXA2: Forkhead box protein A2; SOX17: SRY-box containing gene 17; AFP: α-fetoprotein; ALB: Albumin; CYP1A2: Cytochrome P450 1A2; AAT: α1-antitrypsin.

Figure 3 RT-PCR analysis of differentiated induced pluripotent stem cells on days 5 and 20. Differentiated cells expressed endodermal markers FOXA2 and SOX17 after 5 d of endoderm induction. Liver associated genes AFP, ALB, CK8, CK18, CK19, and HNF-4α mRNA were expressed on day 20. H2O served as a negative control. FOXA2: Forkhead box protein A2; SOX17: SRY-box containing gene 17; AFP: α-fetoprotein; ALB: Albumin; iPSCs: Induced pluripotent stem cells.

Figure 4 Functional analysis of differentiated induced pluripotent stem cells. A: Urea production of differentiated induced pluripotent stem cells (iPSCs); B: Albumin secretion of differentiated iPSCs; C: Glycogen synthesis of differentiated iPSCs as indicated by PAS staining on day 20; D: ICG uptake test of differentiated iPSCs; E: LDL uptake test of differentiated iPSCs. Scale bar = 100 μm. ^bP < 0.01 vs undifferentiated cells; ^dP < 0.01 vs differentiated cells on day 15.