Treatment of ischemic wounds using cultured dermal fibroblasts transduced retrovirally with PDGF-B and VEGF121 genes

The healing of ischemic wounds is a particularly difficult clinical challen ge. In this study, rabbit dermal fibroblasts transduced retrovirally with h uman platelet-derived growth factor B (PDGF-B) and human vascular endotheli al growth factor 121 (VEGF121) genes were used to treat wounds in a rabbit ischemic ear model. The PDGF-B and VEGF121 genes were obtained from human u mbilical vein endothelial cells (HUVECs) by reverse transcription-polymeras e chain reaction, cloned into retroviral vectors under control of the beta -actin promoter, and introduced into primary rabbit dermal fibroblast cells . In vitro results demonstrated that rabbit dermal fibroblasts are transduc ed and selected readily using retroviral vectors, and are engineered to sec rete PDGF-B and VEGF121 at steady-state levels of 150 ng per 10(6) cells pe r 24 hours and 230 ng per 106 cells per 24 hours respectively. These cells were then seeded onto polyglycolic acid (PGA) scaffold matrices and used to treat ischemic rabbit ear wounds. Immunohistochemistry showed intense stai ning for PDGF-B and VEGF121 in the wounds treated with these transduced cel ls compared with the control treatment groups. For the relatively more isch emic distal ear wounds, granulation tissue deposition was increased signifi cantly in the wounds treated with PDGF-B- and VEGF121-transduced cells comp ared with wounds treated with PGA alone. These results demonstrate that gen e augmentation of rabbit dermal fibroblasts with the PDGF-B and VEGF121 gen es introduced into this ischemic wound model via PGA matrices modulates wou nd healing, and may have clinical potential in the treatment of ischemic wo unds.