Effect of pore size on in vitro cartilage formation using chitosan-based hyaluronic acid hybrid polymer fibers

In this study, we successfully developed three-dimensional scaffolds fabricated from the chitosan-based hyaluronic acid hybrid polymer fibers, which can control the porous structure. To determine the adequate pore size for enhancing the chondrogenesis of cultured cells, we compared the behaviors of rabbit chondrocytes in scaffolds comprising different pore sizes (100, 200, and 400 mu m pore size). Regarding the cell proliferation, there was no significant difference among the three groups. On the other hand, glycosaminoglycan contents in the 400 pm group significantly increased during the culture period, compared with those in the other groups. The ratio of type II to type I collagen mRNA level was also significantly higher in the 400 mu m group than in the other groups. These results indicate that our scaffold with 400 mu m pore size significantly enhances the extracellular matrix synthesis by chondrocytes. Additionally, the current scaffolds showed high mechanical properties, compared with liquid and gel materials. The data derived from this study suggest great promise for the future of a novel fabricated material with relatively large pore size as a scaffold for cartilage regeneration. The biological and mechanical advantages presented here will make it possible to apply our scaffold to relatively wide cartilaginous lesions. (C) 2006 Wiley Periodicals, Inc. J Biomed Mater Res 81A: 586-593, 2007.