Heterogeneity of Adenovirus-Mediated Gene Transfer in Cultured Thoracic Aorta and Renal Artery of Rats

Abstract

Abstract Replication-deficient recombinant adenovirus vectors have been used to transfer foreign genes effectively to a wide variety of cell types in vivo and in vitro. We have now used adenovirus containing either the Escherichia coli β-galactosidase (β-gal) gene (AdHCMVsp1LacZ) or the firefly luciferase gene (Ad5-luc3) to test the hypothesis that efficiencies of adenovirus-mediated gene delivery into organ cultures of smooth muscle differ according to the anatomic origin of the muscle. Thoracic aorta and renal artery were isolated from 9-week-old male Sprague-Dawley rats and exposed to adenovirus after 16 hours of incubation with serum-free medium (Dulbecco’s modified Eagle’s medium). With the use of histochemical methods, β-gal staining was noted in both endothelial and adventitial cells but not in the muscular media of thoracic aorta and renal artery exposed to AdHCMVsp1LacZ. The efficiency of the transfection, assessed either by counting of β-gal–stained cells in intact vessels or by measurement of β-gal activity in tissue extracts, was higher in renal artery than thoracic aorta ( P <.05). Consistent with this result, luciferase activity in renal artery exposed to Ad5-luc3 (15.9±2.1×10 6 relative light units per milligram protein) was higher than that in thoracic aorta (8.3±2.0×10 6 , P <.05). To determine whether increased efficiency of adenovirus-mediated gene transfer into renal artery is a function of the replication status of vessels, we assessed [ 3 H]thymidine incorporation. [ 3 H]Thymidine uptake by thoracic aorta was only 63% of that in renal artery ( P <.05), indicating that more proliferating cells are present in renal artery. We conclude that the efficiency of adenovirus-mediated gene transfer into cultured renal artery is enhanced compared with that into thoracic aorta and propose that the increase in efficiency is related to the higher proliferative activity of renal artery.