Review and comparison of culture-techniques for articular chondrocytes

Aim: In-vitro techniques for articular chondrocytes allow the analysis of their metabolism in the presence and absence of mediators or drugs against osteoarthritis or rheumatoid arthritis, as well as the synthesis of de-novo cartilage tissue for implantation into articular defects in vivo. This review aims to give an overview about the basics of different methods of cultivation of articular chondrocytes and about several specific demands (e.g., phenotypical stability with synthesis of aggrecan and type-II collagen, no cell-to-cell contact, low proliferation rates, low matrix molecule turn-over) to such methods. Method: Current techniques for the cultivation of articular chondrocytes and their development were identified via medline. Their evaluation was based on our own experience and on data from the literature. Results: Two- and three-dimensional culture systems are employed to maintain articular chondrocytes in vitro. Two-dimensional cultures (monolayer) support the proliferation of articular chondrocytes, but lead to a de-differentiation to fibroblast-like cells. Three-dimensional set-ups (e.g., organ, alginate, agarose cultures) not only maintain the articular cartilage phenotype, but they also support the re-differentiation of dedifferentiated chondrocytes. Conclusion: The choice of a culture system for in-vitro studies with articular chondrocytes should be adapted to the question asked.