Abstract
Platelets are a recognised potent source of Transforming Growth Factor-1 (TGF1), a cytokine known to promote wound healingand regenerationby stimulating dermal fibroblast proliferation and extracellular matrix deposition. Platelet lysate has been advocated as a novel personalised therapeutic to treat persistent wounds, although the precise platelet-derived growth factors responsible for these beneficial effects have not been fully elucidated. The aim of thisstudy was to investigate the specific role of platelet-derived TGF1in cutaneous wound healing.Using a transgenic mouse with a targeted deletion of TGF1in megakaryocytes and platelets (TGFβ1fl/fl.PF4-Cre), we show for the first-time platelet-derived TGF1 contributes to epidermal and dermal thickening and cellular turnover after excisional skin wounding. In vitrostudies demonstrate human dermal fibroblasts stimulated with platelet lysate containing high levels of platelet-derived TGF1 did not exhibit enhanced collagen deposition or proliferation, suggestingthat platelet-derived TGF1 is not a key promoter of these wound healing processes.Interestingly, human keratinocytes displayed enhanced TGF1-driven proliferation in response to platelet lysate, reminiscent of our in vivofindings. In summary, our novel findings define andemphasiseanimportant roleof platelet-derived TGF1in epidermal remodellingand regenerationprocessesduring cutaneous wound healing.