Abstract
The combined radiation-wound injury is a refractory wound with decreased number or dysfunction of repairing cells and growth factors. This remains a challenge in clinical practice. The object of this study is to evaluate the therapeutic efficacy of a combination of human vascular endothelial growth factor 165 (hVEGF(165)) and human beta-defensin 3 (hBD3) in the treatment of such wounds. A plasmid-carrying hVEGF(165) gene and hBD3 gene was used to transfect rat bone-marrow-derived mesenchymal stem cells (BMSCs). The supernatant from the modified BMSCs significantly promoted the proliferation and cell migration of human endothelial cells and it also inhibited the growth of bacteria and fungus, demonstrating the successful expression of the transfected genes. The hVEGF(165)/hBD3-modified BMSCs were then injected into the sites of combined radiation-wound injury on rats. It demonstrated that wound-healing time was shortened significantly in the treated rats. The granulation tissue formation/maturation, skin appendage regeneration and collagen deposition were also improved significantly. Strong expression of hVEGF(165) and hBD3 was detected in the wound surface at early stage of the healing. The results indicate that topical transplantation of hVEGF(165)/hBD3-modified BMSCs promoted wound healing, and this gene therapy strategy presents a promising approach in the treatment of refractory wounds such as the combined radiation-wound injury.