Wound‐healing properties of trehalose‐stabilized freeze‐dried outdated platelets

BACKGROUND: The wound-healing applications of platelet (PLT)-derived cytokines, proteins, and membranes is accepted but continues to be investigated. In this study, it is demonstrated that stabilized freeze-dried PLTs prepared from outdated PLTs (FDPOs) accelerate wound healing and form tube structures as well as stabilized indated freeze-dried PLTs (FDPIs) and room-temperature fresh PLTs (RT-PLTs). STUDY DESIGN AND METHODS: Experiments were designed to compare in vitro and in vivo wound-healing properties of FDPI, FDPO, and RT-PLT preparations. The concentration of PLT-derived growth factor (PDGF)-betabeta and transforming growth factor (TGF)-beta1 was determined, and the abilities of FDPIs, FDPOs and RT-PLTs to induce endothelial cell proliferation and promote endothelial cell tube formation (cells formed solid spouts connecting neighboring cells to form tube structures) were observed. Wound-healing characteristics were measured by surgically inducing 1-cm(2), full-thickness wounds on db/db mice (n = 10 per group). The wounds were treated with single or multiple doses of FDPIs and FDPOs. Wound closure rate was determined, and histology samples were evaluated for cellular makeup. RESULTS: FDPOs retained the same levels of PDGF-betabeta and TGF-beta1 and were able to promote endothelial cell proliferation and tube formation in vitro as well as FDPIs or RT-PLTs. Multiple applications of FDPO accelerated wound closure and enhanced reepithelialization when compared to untreated wounds in db/db mice. CONCLUSION: FDPOs enhanced wound healing in db/db mice as well as FDPIs and RT-PLTs. Wound closure was obtained 6 days earlier than untreated wounds and histologic examination revealed reduced granulation and increased cellular angiogenesis.