ARTICULAR-CARTILAGE EXPLANT CULTURE - AN APPROPRIATE IN-VITRO SYSTEM TO COMPARE OSTEOARTHRITIC AND NORMAL HUMAN CARTILAGE

Proteoglycan metabolism of normal and histologically mild to moderate osteoarthritic cartilage explants were studied. Explants were obtained from the human knee of donors aged over 40 years. Proteoglycan conten t, synthesis and release were very similar in normal cartilage obtaine d from donors with focal osteoarthritis and cartilage obtained from do nors without any sign of osteoarthritis. This suggests that cartilage obtained from donors with focal osteoarthritis indeed can be considere d as ''normal''. The relatively large surface area -compared to their natural setting in the joint- of cartilage explants in culture did not affect the parameters measured, as there was a strong linear correlat ion between these parameters and the weight of the explants. From our results, we conclude that the use of full depth cartilage tissue expla nts is a reliable way to assess and compare proteoglycan content, synt hesis and release in normal and osteoarthritic cartilage from the same donor.