492. Characterization of the Apical Transduction of Well-Differentiated Mouse Tracheal Cultures by an Equine Lentivirus Pseudotyped with Avian Influenza Coat Proteins

Abstract

The main goal in gene therapy for Cystic Fibrosis (CF) is to transfer the CFTR transgene to the ciliated cells of the upper airways via an easily accessible route and provide long-term therapeutic expression. The ideal route of administration would be lung lumenal instillation but this requires vector uptake from the apical surface of the epithelium. The lung lumen provides many layers of defense to airborne pathogens such as a thick mucus layer and glycocalyx. We addressed these issues by using coat proteins from an influenza virus, which is able to infect the adult lung, to pseudotype a lentiviral vector capable of genome integration and long-term transgene expression. Equine Infectious Anemia Virus (EIAV) based vectors were pseudotyped with coat proteins of Fowl Plague Virus (FPV), an avian Influenza, and we were able to obtain titers greater than 105 iu/ml. Furthermore, we were able to concentrate titers up to 1,000-fold by ultracentrifugation to final titers approaching 108 iu/ml.