Human Cartilage Tissue Engineering Using Type I Collagen/Heparan Sulfate Scaffolds

Abstract

Human Cartilage Tissue Engineering Using Type I Collagen/Heparan Sulfate Scaffolds Introduction: Cartilage engineering may provide a promising alternative solution to current methods of cartilage repair. The aim of this study was to evaluate the suitability of type I collagen (Col I) scaffolds with and without heparan sulfate (HS) to support attachment, proliferation and chondrogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). Materials and Methods: hBMSCs were cultured in Col I, Col I+1%HS, Col I+2%HS and Col I+3%HS scaffolds in both chondrogenic and non-differentiation media for 15 and 30 days. The resulting neo-tissues were analyzed using histochemistry, immunohistochemistry, electron microscopy (EM) and molecular biology. Collagen released into the media by the constructs was also measured by dye-binding assays. Results: Our results showed successful growth and proliferation of hBMSCs on all scaffolds analyzed. Better results were obtained in chondrogenic cultures after 30 days, in which we observed oval/ rounded cells along the scaffolds, and extracellular matrix (ECM) by EM; this ECM was strongly positive for proteoglycan (PG) safranin O staining and staining for type II (Col II). Greater total collagen release was found in supernatants of chondrogenic cultures than in controls. The best results for all analyses were found in scaffolds including HS. Conclusions: We conclude that the Col I and HS scaffolds used in this study are suitable supports for hBMSCs to differentiate toward chondrocyte-like cells in chondrogenic medium. We observe that the addition of HS to Col I scaffolds improves the chondrogenic phenotype of the cells, with Col I+3%HS being the best scaffold.