Linkage of chondroitin-sulfate to type I collagen scaffolds stimulates the bioactivity of seeded chondrocytes in vitro

An increasing amount of interest is focused on the potential use of tissue-engineered articular cartilage implants, for repair of defects in the joint surface. In this perspective, various biodegradable scaffolds have been evaluated as a vehicle to deliver chondrocytes into a cartilage defect. This cell–matrix implant should eventually promote regeneration of the traumatized articular joint surface with hyaline cartilage. Successful regeneration can only be achieved with such a tissue-engineered cartilage implant if the seeded cells reveal an appropriate proliferation rate in the biodegradable scaffold together with the production of a new cartilage-specific extracellular matrix. These metabolic parameters can be influenced by the biochemical composition of a cell-delivery scaffold. Further elucidation of specific cell–matrix interactions is important to define the optimal biochemical composition of a cell-delivery vehicle for cartilage repair. In this in vitro study, we investigated the effect of the presence of cartilage-specific glycosaminoglycans in a type I collagen scaffold on the metabolic activity of seeded chondrocytes. Isolated bovine chondrocytes were cultured in porous type I collagen matrices in the presence and absence of covalently attached chondroitin sulfate (CS) up to 14 days. CS did indeed influence the bioactivity of the seeded chondrocytes. Cell proliferation and the total amount of proteoglycans retained in the matrix, were significantly higher ( p