Enhanced hepatic differentiation in the subpopulation of human amniotic stem cells under 3D multicellular microenvironment

Figure 1 Characteristics of human amniotic membrane and amniotic epithelial cells. A: H and E staining of amniotic membrane. Bar, 50 µm; B: AP staining of amniotic membrane. Positive cells are indicated with arrows. Bar, 100 µm. In A and B, the amniotic membrane was rolled before embedding. Therefore, many layers can be seen in one picture; C: Immunofluorescent staining of frozen section of amniotic membrane. Anti-SSEA4 antibody (green), E-cadherin antibody (red), and DAPI were used; D: Same as C. Anti-TRA-1-81 antibody (green), anti-EPCAM antibody (red), and DAPI were used; E: Direct tissue staining of amniotic membrane. Anti-TRA-1-60 antibody (green) and DAPI were used. Bars in C, D, and E represent 100 µm; F: Colonies formed from cultured amniotic epithelial cells (AECs) and observed by phase-contrast microscopy. Bar to left of F represents 200 µm. Bar to right of F represents 500 µm; G: Frequency of colony formation from primary AECs and adherent AECs. Cells which did not attach to the well surface were removed to purify the amniotic stem cells; H: Gene expression of primary AECs, mesenchymal stem cells(MSCs), and induced pluripotent stem cells(iPSCs) detected by qRT-PCR; I: surface markers of primary AECs verified by flow cytometry.