Platelet rich plasma-derived microvesicles increased in vitro wound healing.

Abstract

Platelet rich plasma (PRP) is a haemoderivative used in clinical practice for the treatment of hard-to-heal wounds. Platelet (PLT) activation is a key factor in the wound healing process leading to the production of extracellular vesicles. We obtained PRP and PRP-derived microvesicles (PLT-MVs) from healthy donors and compared their pro-healing efficacy in an in vitro wound model using human keratinocytes. We evaluated PLT-MVs' direct effect on an in vitro model of wound healing. PRP, PRP activated using calcimycin, and PLT-MVs separated by high speed centrifugation were added to scratched keratinocyte monolayers. Fluorescein diacetate was used in flow cytometry to distinguish PLTs and PLT-MVs from debris, and then, PLT-MVs were quantified on the basis of relative dimensions (Forward Scatter signals). Wound areas were measured at time 0 and after 24 hours and they were healed by 24.80 ± 4.28% in control conditions, while PRP, activated PRP, and PLT-MVs increased closure of 62.94 ± 0.96%, 52.69 ± 17.20% and 52.76 ± 9.44%, respectively. Our results indicate that PRP pro-healing effects were fully replicable by PLT-MVs, suggesting a key role of microvesicles in the healing process and a possible clinical use as an alternative to PRP.