Fig. 5.

In vitroosteogenic differentiation of UCSCs and infant BMSCs

The expression levels of osteocyte-related genes, including alkaline phosphatase (ALP) (A) and osteocalcin (OCN) (B) in UCSCs and infant BMSCs after treatment with the osteogenic factor-induced medium (OIM) for 21 days were detected using RT-qPCR. The expression values of each gene were normalized to the expression of glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The gene expression of undifferentiated cells served as the control group for comparison with the UCSC- and infant ADSC-differentiated osteocyte-like cells, and the relative fold changes were presented. Statistical differences were analyzed using the Mann-Whitney U test for the following groups: differences between UCSCs in the control and OIM groups, differences between infant BMSCs in the control and OIM groups, differences between UCSCs and infant BMSCs in the control groups, and differences between UCSCs and infant BMSCs in the OIM groups. (C) Undifferentiated UCSCs and infant BMSCs were used as controls and stained with Alizarin Red S (ARS). The 21-day osteogenic differentiated UCSCs and infant BMSCs were confirmed with ARS staining and observed using a Nikon Eclipse TS100 microscope (magnification × 200, scale bar = 25 μm). (D) The OD of the ARS staining was measured at a wavelength of 550 nm. The OD of differentiated cells was normalized with that of controls, and the relative fold changes were presented. Mean ± SEM with three experimental replicates were expressed. Statistical significance in comparing the UCSC- and infant BMSC-differentiated osteogenic cells was determined using the Mann-Whitney U test. “ ∗" represented p < 0.05.