This small business Innovation Research Phase I project proposes to define methodology to facilitate the growth of engineered cartilage tissue. Recent studies have demonstrated that the alginate recovered chondrocyte (ARC) method can be used to stimulate isolated adult articular chondrocytes in vitro to form viable cartilaginous tissue with good physiochemical properties. The purpose of this proposal is to define ARC culture conditions for the in vitro formation of pig cartilage tissue. ARC tissue produced in vitro will first be analyzed to determine the biochemical composition, histological appearance and functional properties. Then, the tissue will then be transplanted into full-thickness defects in articular cartilage of adult pigs. At a single time point after transplantation the biochemical composition, histological appearance and functional properties will again be assessed and related to a control defect and initial values. The data will be utilized to determine the feasibility of using the ARC method for the repair of injured or diseased cartilage tissue. Feasibility will be determined by pre-defined criteria related to the assessment of integration, maturation and functional properties after implantation. The proposed research will ideally lead to a commercial method of production of engineered tissue for surgical implantation to repair defects of articular cartilage in humans.