A Fish Skin Collagen/SWNT-COOHs Scaffold With TGF-β1 For Osteochondral Tissue Engineering

Articular cartilage injury caused by trauma and disease is a common problem in department of orthopedics, while it is difficult for clinical treatment, the developing tissue engineering provides a new treatment option. Aiming at repairing the injury of cartilage and subchondral bone, a composite scaffold was fabricated by simulating the orientation of collagen fiber in natural cartilage. In this study, collagen/SWNT-COOHs scaffold with TGF-β1 composed of regenerated fish skin collagen and SWNT-COOHs (0,0.5,1.0 and 2.0 weight percent) were prepared by mixing solubilized pepsin-soluble collagen with solutions of SWNT-COOHs. And the physicochemical properties, cytocompatibility of these composite scaffolds were determined.1. Initial collagen/SWNT-COOHs spongy were prepared using pepsin-soluble fish skin collagen and various fractions of SWNT-COOHs. After crosslinking, collagen/SWNT-COOHs nanocomposite films with TGF-β1 were made by being soaked in the TGF-β1solution. The composite scaffolds were analyzed using FTIR, SEM, CD techniques,et al, and the results showed that:(1)The fish skin collagen in the scaffold retained the typical three helix structure, didn’t occur denaturation and degradation, and were crosslinked with D-ribose; (2) The composite scaffold had a porous structure, all scaffolds had a prosity above 90%.2. The proliferation rate and GAG content of SD rat chondrocytes cultured on the scaffolds with and without TGF-β1in vitro were determined in the 1,3,5,7 day. The results showed that:(1) The chondrocytes had a good adhesion and proliferation in all composite scaffold, even had a adhesion rate above 90% in 2.0 wt% group, proved that the prepared composite scaffolds have good biocompatibility; (2) Compared with the scaffolds without TGF-β1, composite scaffolds with TGF-β1had a higher proliferation rate; (3) As the extension of culture time, GAG content in each composite scaffolds increased, especially in 0.5 wt% group and 1.0 wt% group.3. The scaffold’s effects on the proliferation and differentiation of SD rat mesenchymal stem cell preparation (BMSCs) were tested by MTT method, fluorescence staining, cell total protein content assay and GAG content assay. The results showed that:the composite scaffolds were good to the proliferation and metabolism of BMSCs, can promote BMSCs differentiating into chondrocytes. All the results showed that the 0.5 wt% group composite scaffold was superior to other composite scaffold which may serve as a good scaffold for cartilage tissue engineering.In conclusion, the prepared collagen/SWNT-COOHs scaffold with TGF-β1 were good to the proliferation and differentiation of BMSCs.After further study, the scaffolds may have promising applications for repair of osteochondral defect.