Nguyen et al. instigated a review of extant literature with their supposition that, "... MSC-derived exosomes can regulate ECM synthesis and degradation, chondrocyte proliferation, migration and apoptosis, inflammatory modulation, bone homeostasis, and pain relief. Due to these satisfactory results, therapeutic exosomes may be an innovative medicine and a potential substitute for stem cell therapy for OA patients." The authors also included the below, Figure 2 in their paper, suggesting a mechanism which they purport that exosomes "promote osteoarthritis recovery through modulating inflammatory responses."
Working upon previous research done within the area, Zhang et al. simulated osteochondral defects in a rat model, concluding, "This study demonstrates for the first time the efficacy of human embryonic MSC exosomes in cartilage repair, and the utility of MSC exosomes as a ready-to-use and ‘cell-free’ therapeutic alternative to cell-based MSC therapy." In further investigation in a rabbit model using intra-articular injections combined with hyaluronic acid (HA), Wong et al. concluded, "Human MSC exosomes and HA administered in combination promote functional cartilage repair and may represent a promising cell-free therapy for cartilage repair in patients."