Chondroid Expression by Lapine Articular Chondrocytes in Spinner Culture Following Monolayer Growth

Abstract

When articular chondrocytes from rabbits 2 to 3 months old were transferred from confluent monolayer to spinner culture, they ceased to proliferate but deposited large quantities of metachromatic extracellular material. Return of the suspended cells to monolayer conditions resulted in renewal of DNA and marked depression of sulfated glycosaminoglycan (GAG) synthesis. The GAG of rabbit articular cartilage were heterogeneous and included 4.9% hyaluronate, 11.6% unsulfated chondroitin, 18.7%, disulfated chondroitin and 2.4% dermatan sulfate in addition to chondroitin sulfates 4 and 6. Monolayer cultured chondrocytes produced higher levels of sulfated GAG but much smaller quantities of hyaluronate than did dermal fibrocytes. The GAG synthesized by chondrocytes in spinner culture closely resembled those of whole cartilage or synthesized by whole cartilage in organ culture.