Transforming skin cells into cartilage

Hyaline cartilage, composed primarily of chondrocytes in an extensive extracellular matrix, makes up the embryonic skeleton and persists in adults at the ends of bones, where it provides shock absorption and lubrication of joints. Hyaline cartilage injury often results in the formation of the scar tissue fibrocartilage or even new bone formation leading to growth impairment or osteoarthritis. However, regeneration of cartilage might be possible if researchers can develop a method to generate new chondrocytes.

In this paper, Noriyuki Tsumaki and his team at the Osaka University Graduate School of Medicine, used fibroblasts isolated from adult mouse skin, and expressed proteins that have previously been used to induce pluripotency along with a factor that promotes a chondrocyte fate. This produced cells with traits that resembled chondrocytes and produced cartilage when injected into mice.

The researchers believe this may be an important step toward a therapy that will allow th e repair of cartilage injury using a patient's own skin cells.

The research appears in the Journal of Clinical Investigation.