The Effect of Platelet Rich Plasma versus MSCs Derived Exosomes on the Healing of Burn Injury in Albino Rat: Histological Study

Abstract

Abstract Background The clinical treatment of skin loss due to severe and massive burns or wounds continues to be a major problem in surgical procedures. Although different kinds of dressings and therapies have been developed, but most of them are expensive. Therefore, new strategies are needed to promote and help in wound healing and repair. Recent studies have demonstrated that exosomes help tissue repair because of high stability, non immune rejection and easy control of dosage and concentration. Platelet-rich plasma (PRP) is an autologous concentration of platelets in concentrated plasma. It has been used to promote soft and hard tissue healing. Aim to compare the effect of MSCs derived exosomes versus PRP on the promotion of healing of experimentally induced second degree partial thickness burn injury in adult male albino rats. Methods The thirty-two adult male albino rats were divided randomly into 4 groups. Group I (control). Group II (burn injury group) that will be left for spontaneous healing. Group III (burn injury treated with PRP intradermal injection). Group IV (burn injury treated with intradermal MSCs derived exosome). All the animals were sacrificed at 7th day (subgroup a) and 21th day (subgroup b). The skin biopsies will be taken and processed for light microscope examination. Results H&E stained section of untreated burn (subgroup IIa) showed coagulative necrosis in epidermis and papillary layer of the dermis. Sign of epithelial migration from the edge of the wound appeared. In Subgroup IIb the surface of the wound was covered by an eschar that converted partial thickness into complete thickness. This resulted in formation of granulation tissue in the dermis. In Subgroup IIIa showed the formation of thin layer of epidermis containing undifferentiated keratinocytes. The underlying dermis contained collagen fibers and beginning of new hair follicles formation. Some specimens in Subgroup IIIb revealed thin epidermis with incomplete differentiation of keratinocytes. Numerous hair follicles were detected in the dermis. However some specimens showed thickened epidermis with presence of rete ridges. The dermis showed few irregularly distributed collagen fibers in granulation tissue with absence of skin appendages. In exosome treated group (subgroup IVa) showed thin epidermis with well differentiated keratinocytes. The dermis contained collagen fibers with absence of skin appendages. Subgroup IVb was more or less similar to the control group. Conclusion The current study revealed that burn treated exosomes group was better than PRP treated group. In addition PRP treated group revealed hyperplastic changes in epidermis with delay in remodeling phase of burn healing.