Polycations increase the efficiency of adenovirus-mediated gene transfer to epithelial and endothelial cells in vitro

Abstract

Recombinant adenoviruses are being developed for gene therapy for cystic fibrosis and other lung diseases, and for prevention and treatment of vascular thrombosis. A major limitation to the clinical utility of adenoviruses os the low efficiency of gene transfer achieved in vivo. In addition, little is known about the initial interactions between adenoviruses and the target cell. To address the hypothesis that the negative change presented by membrane glycoproteins reduces the efficiency of adenovirus-mediated gene transfer, primary cultures of human airway, Madin-Darby canine kidney cells, an immortalized cystic fibrosis airway epithelial cell line, and primary cultures of sheep pulmonary artery endothelium were infected with recombinant adenovirus containing the E. coli lacZ reporter gene (Ad2βgal2) in the presence of various polyions. For each cell type, adsorption of Ad2βgal2 in the presence of the polycations polybrene, protamine, DEAE-dextran, and poly-L-lysine significantly increased the percentage of cells that express lacZ. The polyanion heparin did not significantly alter gene transfer efficiency, but completely abrogated the effects of polycations. These provide evidence that negatively changed moieties on the cell surface reduce the efficiency of adenivirus-mediated gene transfer, adenoviruses and the cell surface may improve the potential clinical application of these vectors.