Characteristics of tissue-engineered cartilage on macroporous biodegradable PLGA scaffold

Background: The purpose of this study was to establish in vivo culture of chondrocytes on biodegradable, poly-D,L-lactic-co-glycolic acid (PLGA) scaffolds and to analyze the characteristics of the reconstructed cartilage. Methods: In vitro cultured chondrocytes that were grown on a polyhydroxyethyl methacrylate (poly-HEMA) coated dish were seeded onto the PLGA scaffolds to make a cell-polymer construct before implantation. One cell scaffold construct was carefully implanted in the subcutaneous pocket of a nude mouse and another cell-free scaffold was implanted in the opposite side of the same nude mouse as the control. Morphologic, biochemical, and immunohistochemical. characteristics of cells cultured within the PLGA constructs were examined after 8 weeks and 16 weeks of harvesting in the nude mouse. Results: New cartilage began to be generated in the period of 8 weeks and the neocartilage formation was accomplished in 4 months with the exact dimensions of the original scaffold in this in vivo study. All the explants showed the irregular shape of viable chondrocytes within normal lacunae and a mature cartilaginous matrix, and they positively immunostained for collagen type II. Conclusion: The new tissue-engineered cartilage in vivo on PLGA scaffolds displayed the biochemical characteristics of cartilage tissue, and it showed chondrocyte-specific phenotypes and morphology that were similar to the native cartilage.