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Wound Healing Properties of Reconstituted Freeze-Dried Platelets

The use of fresh platelets has gained value in medicine as an essential part of wound treatments. This is not surprising since platelets contain a number of bioactive factors that contribute to the process of wound healing, such as platelet-derived growth factor (PDGF) and transforming growth factor (TGF). Fresh platelets’ short shelf life limits platelet-based therapies. If platelets can be stabilized in freeze-dried form (FDP) then long-term storage as well as pathogen inactivation methods become possible. Adlyfe and Oregon Freeze-Dry have been developing technology to stabilize freeze-dried human platelets that can be subjected to gamma irradiation and stored for a long duration. Upon reconstitution, irradiated FDP retained growth factors PDGF-AB, PDGF-BB, and TGF-B1 in quantities similar to fresh platelets as judged by capture ELISA. The rehydrated FDP promoted new DNA synthesis and cellular proliferation of primary human dermal fibroblasts and endothelial cells (HUVECs) similar to fresh platelets. The FDP also promoted remodeling of extracellular matrix by accelerating fibroblast-mediated contraction of collagen gels and stimulated HUVECs to undergo angiogenesis and form capillary structures in vitro. Therefore, we conclude that FDP and fresh platelets have comparable in vitro wound healing potential. Preclinical wound healing studies in diabetic mice are under way and further development will allow FDP to be a safe and well-suited alternative to fresh platelets for wound healing applications.