Fig. 5.

Immunohistochemistry for type 2 collagen (green) in ADSC-SS cultured on medium with 10% FBS (negative control), 10% PRP, and StemPro (positive control) on days 7 (a–c), 14 (d–f), and 21 (g–i); cell nucleus (oval shape) in blue colour (DAPI) is shown by yellow arrows; the silk fibroin scaffold was also stained blue. Type 2 collagen in the cytoplasm is shown by a red arrow; type 2 collagen was outside the cells is shown by white arrows. Cells were observed at × 200 magnification on an Olympus Fv1200 confocal microscope (yellow scale bar = 100 μm)