Therapeutic angiogenesis for ischemic syndromes

Diseases caused by atherosclerosis are the most common causes of morbidity and mortality in western societies. The inadequacy of current therapeutic m odalities is most pronounced in the significant proportion of patients with arterial obstructive disease, in whom anatomical and technical limitations rule out the possibility of angioplasty or surgery. Therefore, less invasi ve approaches are necessary to treat these patients. The development of col lateral circulation improves blood now to ischemic tissues and to alleviate ischemia-related symptoms. Our project concentrates on enhancement of the natural mechanism of angiogenesis by adenoviral based vector encoding vascu lar endothelial growth factor as an angiogenic factor. The aim of our study was to determine the efficacy of human vascular cell infection by adenovir al based vectors in vitro and in vivo. Human saphenous vein endothelial cel ls and smooth muscle cells were infected by adenoviral vectors encoding the lacZ and VEGF genes (rAdlacZ, rAdVEGF). VEGF expression by adenoviral vect or-infected cells was detected by western analysis and its biological activ ity was examined by proliferation assay. The feasibility of adenoviral base d gene transfer in vitro was evaluated after direct femoral artery injectio n of rAdlacZ in the rat. Vascular endothelial and smooth muscle cells expre ssed high levels of VEGF following rAdVEGF infection. The mitogenic effect of VEGF was validated by threefold increase in EC proliferation rate in com parison to the control groups. In vivo gene transfer was demonstrated using lacZ gene transfer to arterial wall cells in the superficial femoral arter y. Efficient adenoviral based gene delivery was demonstrated bath in vitro and in vivo. VEGF over-expression enhanced endothelial cell proliferation, which is the key step for induction of angiogenesis.