Immunomodulatory Strategies for Cartilage Regeneration in Osteoarthritis.

Osteoarthritis (OA) is the most prevalent musculoskeletal disorder and a leading cause of disability globally. Although many efforts have been made to treat this condition, current tissue engineering (TE) and regenerative medicine strategies fail to address the inflammatory tissue environment that leads to the rapid progression of the disease and prevents cartilage tissue formation. First, this review addresses in detail the current anti-inflammatory therapies for OA with a special emphasis on pharmacological approaches, gene therapy, and mesenchymal stromal cell (MSC) intra-articular administration, and discusses the reasons behind the limited clinical success of these approaches at enabling cartilage regeneration. Then, we analyze the state-of-the-art TE strategies and how they can be improved by incorporating immunomodulatory capabilities such as the optimization of biomaterial composition, porosity and geometry, and the loading of anti-inflammatory molecules within an engineered structure. Finally, the review discusses the future directions for the new generation of TE strategies for OA treatment, specifically focusing on the spatiotemporal modulation of anti-inflammatory agent presentation to allow for tailored patient-specific therapies. Impact statement Osteoarthritis (OA) is a prevalent and debilitating musculoskeletal disorder affecting millions worldwide. Despite significant advancements in regenerative medicine and tissue engineering (TE), mitigating inflammation while simultaneously promoting cartilage tissue regeneration in OA remains elusive. In this review article, we discuss current anti-inflammatory therapies and explore their potential synergy with cutting-edge cartilage TE strategies, with a special focus on novel spatiotemporal and patient-specific anti-inflammatory strategies.