Exosomes loaded Peptide Hydrogel scaffold with anti-inflammatory function and in situ stem cell recruitment properties for repairing sports-related cartilage injuries

Sports-related injuries often cause damage to the articular cartilage, a structure characterized by the absence of blood vessels, nerves, and lymphatics, which hinders its ability to heal. Current clinical interventions fall short in reversing cartilage degeneration or regenerating fibrocartilage, leading to less than satisfactory outcomes. Furthermore, the use of hydrogel-based stem cell therapies has been hampered by the poor survival of transplanted stem cells in the inflamed environment of the injured cartilage, and by the uncontrolled differentiation of these cells due to cytokines, limiting their clinical application. In our study, we developed a novel approach using a biodegradable peptide hydrogel that incorporates anti-inflammatory exosomes known to stimulate stem cell growth and peptides that recruit endogenous stem cells to the site of injury. This system sidesteps the need for exogenous stem cells by utilizing the body's own healing mechanisms, guided by specific peptides. Once at the site of injury, these stem cells are stimulated to differentiate into cartilage tissue through a combination of TGF-β1 and the exosomes, which also help to suppress inflammation and promote healing. This research offers a promising new strategy for treating sports-related cartilage injuries, presenting a more effective and less invasive option for patients.