Mesenchymal Stem Cells in Oriented PLGA/ACECM Composite Scaffolds Enhance Structure-Specific Regeneration of Hyaline Cartilage in a Rabbit Model

Figure 7

Toluidine blue, safranin O, and immunohistochemical staining of the collagen type II content of repaired cartilage at 24 weeks postimplantation (a–o). (a) and (e) The defect in the untreated group was filled with fibrotic tissue but did not stain for cartilage-specific matrix. (f) and (j) The defect region was filled with repaired cartilage, with light staining for cartilage-specific matrix. (k) and (o) The cartilage defect was filled with regenerated cartilage, and the deep regenerated area stained strongly for cartilage-specific matrix. (p–r) The histological grading, cartilage thickness, and Young’s modulus, respectively, of repaired cartilage at 12 and 24 weeks postsurgery (bars: 50 μm). .