Improved Healing of Colonic Anastomosis with Allotransplantation of Axillary Skin Fibroblasts in Rats

Objective: Colonic anastomosis is associated with serious complications leading to significant morbidity and mortality. Fibroblasts have recently been introduced as a practical alternative to stem cells because of their differentiation capacity, anti-inflammatory, and regenerative properties. The aim of this study was to evaluate the effects of intramural injection of fibroblasts on the healing of colonic anastomosis in rats. Materials and Methods: Inbred mature male Wistar rats were used in this experimental study (n=36). Fibroblasts were isolated from the axillary skin of a donor rat. In the sham group, manipulation on descending colon was done during laparotomy. A 5 mm segment of the colon was resected, and end-to-end anastomosis was performed. In the control group, 0.5 ml of phosphate buffer saline (PBS) was injected into the colonic wall and in the treatment group, 1×106 fibroblasts were transplanted. Following euthanasia on day 7, intra-abdominal adhesion, leakage and peritonitis were evaluated by necropsy. Mechanical properties were assessed using bursting pressure and tensile tests. Inflammation, angiogenesis, and collagen deposition were examined histopathologically. Results: The mean scores for adhesion and leakage were decreased in the treatment group versus control samples. Lower infiltration of inflammatory cells was observed in the treatment group (P=0.03). Angiogenesis and collagen deposition scores were significantly increased in the fibroblast transplanted group (P=0.03). Tensile mechanical properties of the colon were significantly increased in the treatment group compared to the control sample (P=0.01). There was no significant difference between the control and treatment groups in terms of bursting pressure (P=0.10). Positive weight changes were found in sham and treatment groups, but the control rats lost weight after 7 days. Conclusion: The results suggested that allotransplantation of dermal fibroblasts could improve the necroscopic, histopathological, and biomechanical indices of colonic anastomosis repair in rats.