Effect of Bone Marrow Derived Mesenchymal Stem Cells on Healing of Induced Full-Thickness Skin Wounds in Albino Rat

Abstract

Mesenchymal stem cells have delivered new approaches to the management of wound healing in severe skin injuries. This work was planned to evaluate the effect of bone marrow-derived mesenchymal stem cells (BMSCs) on healing of induced full thickness skin wounds in albino rats using topical & systemic injections. Forty adult male albino rats were classified into 2 groups after induction of full thickness skin wound; untreated group and stem cell-treated group. The latter was further subdivided into topically and systemically treated ones. BMSCs were isolated & labeled by PKH26 before injection. Healing of wounds was evaluated grossly. Skin biopsies were obtained one & three weeks after wound induction. Sections were stained with Hematoxylin & Eosin, Masson's trichrome and immunohistochemichal stain for vascular endothelial growth factor (VEGF). Epidermal thicknesses and mean area percent of both collagen fibers & VEGF immunopositive cells were measured using image analyzer & results were subjected to statistical analysis. PKH26 fluorescent-labeled cells were found in the regenerated epidermis, hair follicles and dermis in BMSCs-treated groups. By the end of the third week, the wounds of BMSCs-treated groups showed full regeneration of epidermis, re-organization of collagen and decrease in VEGF immunopositive cells. Delayed wound healing was seen in 20% of systemically treated rats. Significant increase in the mean area percent of collagen fibers was detected in topically treated group. Both methods of BMSCs injection were effective in healing of full thickness skin wound but topical method was more effective.