Comparative Efficacy of Exosomes Derived from Different Mesenchymal Stem Cell Sources in Osteoarthritis Models: An In Vitro and Ex Vivo Analysis.

Osteoarthritis (OA) is a prevalent and debilitating joint disorder that affects a substantial proportion of the global population, underscoring the urgent need for therapeutic strategies that extend beyond symptomatic management. Although mesenchymal stem cells (MSCs) have emerged as a promising therapeutic modality, their clinical application remains constrained by several inherent limitations. This study explores a cell-free alternative by investigating the therapeutic potential of exosomes derived from bone marrow (BMSCs), adipose tissue (ADSCs), and umbilical cord (UMSCs) MSCs in mitigating OA pathogenesis, utilizing both in vitro and ex vivo models. Exosomes from each MSC source were isolated and characterized through nanoparticle tracking analysis, transmission electron microscopy, and Western blotting to confirm their identity and purity. Subsequently, their chondroprotective, anti-inflammatory, and regenerative properties were systematically assessed through evaluations of cell viability, expression profiles of inflammatory and chondroprotective markers, and chondrocyte migration assays. The results demonstrate that all three types of MSC-derived exosomes (MSC-Exos) exhibit low cytotoxicity while significantly suppressing proinflammatory markers and enhancing the expression of chondroprotective genes. Notably, BMSC-Exos and UMSC-Exos displayed superior efficacy in attenuating inflammation, promoting cartilage protection, and inhibiting chondrocyte apoptosis. Furthermore, all MSC-Exos markedly enhanced chondrocyte motility, a critical component of cartilage repair. Collectively, these findings support the therapeutic promise of MSC-Exos, particularly those derived from BMSCs and UMSCs, as a targeted, cell-free approach for the treatment of OA compared to ADSCs. By modulating inflammation, promoting cartilage regeneration, and preventing chondrocyte apoptosis, MSC-Exos may serve as a viable and scalable alternative to current MSC-based therapies for this widespread degenerative disease.