Clinical Effect of Mesenchymal Stem cell-Derived Microvesicles as Adjunctive Treatment to Surgery on Healing of Distal Limb Chronic Wounds in Arabian Horses

DISTAL limb wounds in horses account for more than 60% of all wounds. This study described the clinical effect of mesenchymal stem cell -derived microvesicles (MVs) on healing of equine distal limb chronic wounds. Twelve Arabian horses with distal limb granulating wounds (Group I, n=6) or ulcerated wounds (Group II, n=6) were treated surgically either by excision of the granulating masses or debridement of ulcers. In group I, the horses were divided randomly into two subgroups (3 horses each); subgroup 1 was given two doses of topical and subcutaneous injection of MVs after surgery. Subgroup 2 (control) was treated only by surgery. Group II was divided randomly into two equal subgroups; subgroup 1 was given one dose of topical and subcutaneous injection of MVs after surgery and subgroup 2 was treated by debridement (control). Healing progression was documented using digimizer image analysis software and data were statistically analyzed. The mean areas of the granulating and ulcerating wounds were 81.71 +/- 3.25 cm2 and 18.91 +/- 1.78 cm2, respectively. In group I, complete wound healing was achieved on days 70 +/- 3.5 and 100 +/- 4.32 in subgroups 1 and 2, respectively. However, complete wound healing was achieved in group II on days 27 +/- 2.3 and 41 +/- 3.1 in subgroups 1 and 2, respectively. There were statistically significant differences in wound area reduction between the two subgroups in both groups (P< .05). In conclusion, this preliminary study indicated that topical and subcutaneous injection of MVs after surgical interferences may enhance healing of the chronic wounds in distal limbs of horses.