Mesenchymal stem cells as a potential pool for cartilage tissue engineering.

Osteoarthritis (OA) resulting from trauma, degenerative or age-related disease presents a major clinical challenge due to the limited repair capacity of articular cartilage. This poor self-repair capacity of osteochondral defects has resulted in the development of a wide variety of new treatment approaches. Although the use of chondrocytes in applications of cartilage tissue engineering is still prevalent, concerns associated with donor-site morbidity, cell de-differentiation and the limited lifespan of these cells have brought the use of mesenchymal stem cells (MSCs) to the forefront of such applications. Therefore, in the last two decades MSCs have come into the focus of connective tissue engineering and regenerative medicine and have become increasingly sought after as an alternative cell source for improving well-established methods of osteochondrotic cartilage defect repair such as the Autologous Chondrocyte Transplantation method, but are also being tested as an ideal cell source in combination with newly developed implantable scaffolds or as a target/carrier cell in other new concepts of regenerative medicine. However, up to now, although in animal models MSCs have already shown significant potential for cartilage repair and novel approaches using MSCs as an alternative cell source to patient-derived chondrocytes are being tested, much more research is needed before feasible clinical application of MSCs becomes reality.