Mechanisms and challenges of mesenchymal stem cells in the treatment of knee osteoarthritis.

In this editorial, we comment on the recent article by Xiao et al, focusing on their investigation into whether the therapeutic efficacy of serum-free human umbilical cord mesenchymal stem cells (MSCs) differs from that of serum-containing human umbilical cord MSCs in a mouse model of knee osteoarthritis (OA). The incidence of OA has significantly increased in recent years, primarily owing to sports-related injuries or degenerative diseases. However, the regenerative capacity of articular cartilage remains limited, necessitating artificial joint replacement for patients with advanced OA to enhance the quality of life. MSCs have been widely used in the clinical treatment of OA owing to their multidirectional differentiation potential and immunomodulatory effects. The focus of this paper lies in elucidating the mechanism underlying MSC transplantation for the treatment of knee OA, while also addressing the challenges encountered in MSC therapy and outlining future directions.