Decellularized Cartilage as a Bioactive Biomaterial for Cartilage Tissue Engineering

Abstract

Damage to articular cartilage is a particularly perplexing clinical problem because cartilage has a limited ability to repair itself. Currently, clinical techniques to treat articular cartilage regeneration fail at regenerating fully functional articular cartilage and in extreme cases the cartilage regeneration may lead to the need for a total joint replacement. Recently, tissue engineering approaches to articular cartilage repair have explored the use of extracellular matrix (ECM) based materials for enhanced regeneration of cartilage. ECM-based materials are of interest in the tissue engineering field because in all tissues the ECM plays an important role in cell function by affecting cell communication, migration, and differentiation. Tissues can be decellularized to remove any immunogenic remains of cells to obtain an acellular ECM material to be used as a tissue engineering scaffold. The objective of this thesis was to evaluate a chemical and physical method for decellularizing articular cartilage and characterizing the cellular response to both the un-modified material and the material incorporated into microsphere-based scaffolds. Cells cultured in the presence of decellularized cartilage (DCC) alone exhibited increased expression of chondrogenic gene markers including collagen II, Sox9, and aggrecan relative to negative controls and TGF-β. Additionally, encapsulation of DCC in poly(lactic-co-glycolic acid) (PLGA) microspheres had comparable effect on cells in vitro compared to the encapsulation of TGF-β. These results indicate that DCC is a promising material for future use in cartilage tissue engineering and is worthy of additional future investigation.