An Allogeneic Platelet-Derived Hydrogel Improves Neo-Vascularisation in Full Thickness Wounds

Platelets are a reservoir of growth factors, cytokines and chemokines involved in spontaneous wound repair. In this study, a novel platelet-rich and fibrin-rich hydrogel was generated from expired platelet components that would otherwise have been transfused. The material contained physiological concentrations of transforming growth factor β1 (TGF-β1, platelet-derived growth factor AB (PDGF-AB), PDGF-BB, insulin-like growth factor-1 (IGF-1), fibroblast growth factor 2 (FGF-2), and epidermal growth factor (EGF). The effect of the hydrogel on wound repair was investigated in SKH-1 mice. Full thickness dorsal wounds were created on the mice and treated with the hydrogel at various concentrations. Immunohistochemical staining with CD31 (endothelial cell marker) revealed that wounds treated with the hydrogel showed significantly enhanced vascularisation in the wound bed. Moreover, high levels of interleukin-6 (IL-6) and KC (IL-8 homologue) in treated wounds were sustained over a longer period of time, compared to untreated wounds. We postulate that sustained IL-6 is a driver, at least partly, of enhanced vascularisation in full thickness wounds treated with the hydrogel. Future work is needed to explore whether this novel hydrogel can be utilised as a treatment option when vascularisation is a critical limitation.