Experimental assessment of regenerative properties of platelet rich plasma on the human skin - a review

Abstract

Several studies demonstrated the favorable effects of platelet rich plasma (PRP) on the skin and promoted its wide use in clinical practice. The growth factors stored in platelet alfa-granules allow for the tissue regeneration and the main fields of application of PRP in current clinical practice are the cartilage and musculoskeletal defects, osteoarthritis and other bone disorders, chronic and difficult to heal wounds, and aesthetic procedures. The relevant number of different PRP preparation protocols may explain the inconsistency of the different clinical outcomes reported in the literature. Despite the technological advances in PRP preparation, the objective assessment of the clinical efficacy of PRP from the literature reports still is difficult due to the low homogeneity of the samples in terms of both inclusion criteria and size. Therefore, it might be useful to establish standardized and reproducible experimental models to confirm and objectively measure the effectiveness of the available clinical results. Many experimental investigations have been carried out to objectively assess the effectiveness of PRP and platelet gel on several tissues. As far as the skin is concerned, the studies carried out to date are limited to fibroblasts in in-vitro culture models or to collagen, vascular supply, epithelium, and hair follicle in in-vivo models. The skin, however, is a very complex organ, where different cell lines coexist and feature complex mutual interaction. A model that combines the advantages of both in-vitro and in-vivo cultures is the ex-vivo model. The demonstration of the platelet derived growth factors effects through the ex-vivo human full-thickness skin culture model is a keystone to support the evidence of the PRP effectiveness, as it represents an objective, fast, reproducible, and ethical investigational method.