Figure 3

Negative control and Dll4 mRNA tracking of hMSCs during osteogenesis. Representative bright field and fluorescence images of hMSCs after 3 d, 5 d, and 7 d of osteogenic induction. (A) Green fluorescence indicates the signal of negative control of random probe. (B) Dll4 mRNA expression tracking of hMSCs during osteogenic induction after 3 d, 5 d, and 7 d of osteogenic induction. Green fluorescence indicates Dll4 mRNA expression. Yellow arrows indicate the differentiated cells expressing Dll4 mRNA. (C) Mean fluorescent intensity of random probe in hMSCs at different time points under control and induction group. (D) Mean fluorescent intensity of Dll4 mRNA expression in hMSCs at different time points under control and induction group. Control group: cells were cultured and maintained in basal medium. Induction group: Cells were cultured in basal medium and induced by osteogenic induction medium after 2 days of cell seeding. Images are representative of at least three independent experiments. Scale bar: 50 μm. Data represent over 100 cells in each group and are expressed as mean ± s.e.m. (n = 3). p-values were calculated using a two-sample t-test with respect to day 2. *p < 0.05; **p < 0.01; ***p < 0.005.