Fig. 6

In vivo subcutaneous angiogenesis and osteogenic differentiation in HUVECs after OCT4-30Kc19 and BMP4 treatment. (A) Schematics of procedure of in vivo experiments, both for subcutaneous model and cranial defect model. HUVECs treated with OCT4-30Kc19 and BMP4 were seeded into gelatin-heparin scaffold. After cell-seeded scaffold were delivered into subcutaneous tissue, angiogenesis and osteogenic differentiation capacity was analyzed. Also, cell-seeded scaffolds were put in the defect area of sagittal crest of mice, bone regeneration capacity was analyzed. (B) Masson’s trichrome staining (MTC) of cell seeded gelatin-heparin scaffolds. Cells without treatment, only OCT4-30Kc19 treatment, only BMP4 treatment, both OCT4-30Kc19 and BMP4 treatment were each seeded on the scaffold and delivered into mouse subcutaneous tissue. After 6 weeks, MTC staining was performed. The sample treated with OCT4-30Kc19 and BMP4 showed the highest accumulation of collagen. Collagen is stained in blue. Scale bar, 200 μm. (C) Immunofluorescence staining of angiogenesis marker, TIE-2. TIE-2 was detected by anti-TIE 2-antibody (1:400). Both treatments of OCT4-30Kc19 and BMP4 on HUVECs elevated the expression of TIE-2, which indicates angiogenesis. Blue, green represent the nucleus and TIE-2 protein, respectively. Scale bar, 100 μm