Cell-based therapy options for osteochondral defects. Autologous mesenchymal stem cells compared to autologous chondrocytes

Cartilage defects are multifactorial and site-specific and therefore need a clear analysis of the underlying pathology as well as an individualized therapy so that cartilage repair lacks a one-for-all therapy. The results of comparative clinical studies using cultured chondrocytes in autologous chondrocyte implantation (ACI) have shown some superiority over conventional microfracturing under defined conditions, especially for medium or large defects and in long-term durability. Adult mesenchymal stem cells can be isolated from bone marrow, have the potency to proliferate in culture and are capable of differentiating into the chondrogenic pathway. They represent a promising versatile cell source for cartilage repair but the ideal conditions for cultivation and application in cartilage repair are not yet known or have not yet been characterized. Adding a scaffold offers mechanical stability and advances chondrogenic differentiation for both possible cell sources.