Fig. 8From: Hierarchical porous ECM scaffolds incorporating GDF-5 fabricated by cryogenic 3D printing to promote articular cartilage regenerationHistomorphological evaluation of repaired tissue at 6 weeks. Histological (H&E, safranin O, and Sirius red staining) and immunohistochemical staining (collagen II) of the defect area. Solid arrows indicate the repair interface. (N: normal cartilage; R: repaired cartilage). Scale bars are 500 μmBack to article page