Do stem cells promote healing of experimentally inducedwound injury in adult male dogs? Histological andimmunohistochemical study

BackgroundStem cells have generated considerable interest and promise as a potential sourceof cells for cell-based therapeutic strategies, primarily owing to their intrinsic ability toself-renew and differentiate into multiple functional cell types. Stem cells have beenutilized to regenerate viable skin tissue.Aim of the workThe present study was carried out to investigate the healing capacity of autologousbone marrow-derived mesenchymal stem cells (BM-MSCs) and its regenerative rolein experimentally induced wound injury.Materials and methodsThe present study was carried out on 18 dogs. The study included two groups.Group I (n=6) was used a negative control and received no treatment. Group II wasused as an experimental group and was divided into subgroup IIa (n=6), used as apositive control, and subgroup IIb (n=6). Subsequently, three circular wounds weremade using a 10-mm diameter skin punch biopsy in the animals of subgroup IIa andsubgroup IIb to induce wound injury. Group IIb were injected subcutaneously withundifferentiated mesenchymal stem cells at a dose of 1.4–1.6×106/ml in 5 ml sterilesaline into the wound bed for 2 weeks after wound injury; skin biopsies from thewound areas were prepared for staining by H E and immunostaining using anti-Thy-1(CD90) antibodies.ResultsBM-MSC-treated wounds showed accelerated wound closure, with increasedre-epithelialization of the epidermis, increased dermal cellularity and hair follicles,and angiogenesis. This was confirmed by the apparent increased immunoreactivity ofthe cell content of anti-rat Thy-1 CD90 cells in the dermis.ConclusionAsubcutaneous injection of autologous undifferentiated mesenchymal stem cellsinto the wound bed is an effective method of wound regeneration and can be usedin chronic wounds as in a diabetic foot.