P543
The healing of cutaneous wounds is a very efficient process despite being very complex. Under certain pathological conditions healing may be impaired, prolonging the healing process and eventually leading to medical intervention and the chronicity of the wound. Exosomes are secreted extracellular vesicles present in biological fluids where they play a key role in intercellular communication at the tissue, organ and organismal levels. Given that human breast milk contains abundant maternal extracellular vesicles (MEVs) with pro-regenerative and immunomodulatory properties, the aim of the present study was to evaluate if topical application ofMEVs into open wounds would be beneficial for healing. Full-thickness excision wounds of 4-mm diameter were created in the dorsal skin of C57BL/6 mice and topical application of 20 micrograms of human MEV isolated at weeks 9, 11, 12 and 15 postpartum of breastfeeding were placed onto the open wounds. Control wounds were vehicle-treated. Macroscopic measurements up to 7 days postwounding revealed that the area of the wound treated with MEV significantly decreased compared with controls. Histological analyses at day 7 post-wounding showed no differences in the granulation tissue area between groups. ..
