Figure 4.

Effects of insulin on the immunophenotype and differentiation capacity of UCM-MSC. (a) UCM-MSC grown in conventional 10% FBS-containing media (SCM) and serum-deficient media supplemented with 10 μM insulin (SFM + insulin) for one passage were analyzed for surface expression of CD34, CD45, CD31, CD90, and CD105 by flow cytometry. Histograms show the data of a representative experiment from three independent studies with similar results (black line: samples; gray filled: corresponding isotype controls). (b) UCM-MSC grown in different conditions over one passage (as described in (a)) were reseeded into 12-well plates. The cells were then left uninduced in SCM (control) or were induced to differentiate into either adipocytes (adipogenic induction) or osteoblasts (osteogenic induction) in appropriate differentiation media for 21 days. After staining the cultures with oil red O or alizarin red S, the cells were photographed under identical brightness and contrast conditions (left), and then the deposited oil red O and alizarin red S were eluted, followed by absorbance measurement at 450 and 560 nm, respectively (right). Scale bar, 500 μm. For both bar graphs, data are shown as mean ± SD, and error bars indicate SD (n = 3). ^∗p < 0.05 versus control by one-way ANOVA with Fisher's test (ns: not significant between indicated groups).