Fig. 7: Expression of extracellular matrix proteins in the cartilage defect 6 and 12 weeks after the injection of the hydrogels.

a Toluidine blue staining of the cartilage. b Immunochemistry for aggrecan expression in the defect area (Scale bar = 500 μm). c Immunochemistry for collagen II expression in the defect area. Scale bar = 500 μm. d Immunochemistry for collagen I expression in the defect area. Scale bar = 500 μm.