Purpose: To evaluate the efficiency of recombinant adeno-associated virus (rAAV)-mediated CD151 gene delivery in promoting neovascularization and improving blood perfusion in the skeletal muscle of the rat hind-limb ischemia model.
Methods: CD151 was constructed into the rAAV vector. Twelve Wistar rats were randomly divided into 2 groups of 6 rats each and then intramuscularly injected with rAAV-CD151 or rAAV-GFP, respectively, in one hind limb. Two weeks after gene delivery, the femoral arteries in the treated limbs were excised to establish the model of hind-limb ischemia. Expression of the transgene product CD151 was confirmed by Western blot and the reverse transcription polymerase chain reaction. The skin temperature, angiographic score, and capillary density of the hind limb were measured to assess blood perfusion and neovascularization 6 weeks after transfection.
Results: Compared to the group transfected with GFP, the CD151 group showed a 63% higher angiographic score (p<0.05) and an 18% increase in capillary density (p<0.05). In addition, the mean skin temperature of the AAV-CD151-transfected hind limbs was equivalent to the level of the contralateral nonischemic limb, whereas the limb temperature in the GFP-transfected rats was significantly lower than the nonischemic control. The expression of CD151 in the ischemic hind limb injected with rAAV-CD151 was significantly higher than limbs injected with rAAV-GFP. The CD151 mRNA and protein expression was persistently observed in the injected muscle for at least 6 weeks after injection, while no human CD151 mRNA could be detected in remote organs or rAAV-GFP-injected muscles.
Conclusions: This study demonstrates that the rAAV-mediated CD151 gene transfer into rat skeletal muscles is efficient, stable, and has no ectopic expression. Moreover, rAAV-mediated CD151 gene transfer stimulates neovascularization, especially arteriogenesis, and thereby improves blood perfusion in a rat hind-limb ischemia model. These findings suggest that CD151 could be a new target for neovascularization therapy in ischemic disease, and rAAV-mediated CD151 gene transfer may be useful for treatment of ischemic disease.