170. In Vitro Transduction of Cells To Determine Tropism Using Viral-Like Particles Derived from JC Virus VP1

Abstract

Top of pageAbstract Gene therapy for treatment of neurological diseases is a rapidly emerging new field. Virus-Like Particles (VLP) originating from the human polyoma virus JCV are being evaluated as a delivery vector for the central nervous system (CNS) because JCV preferentially infects both oligodendrocytes and astrocytes. In developing a gene delivery system with JCV VLP, we have optimized both the production of recombinant VP1 from JCV in insect cells and the packaging conditions for purified VP1 and plasmid DNA. Using VP1-VLP containing plasmid DNA expressing EGFP, we have performed transduction assays in a panel of human and rodent brain-derived and non-brain derived cells in order to characterize the in vitro tropism and species specificity of VP1-VLP. From the survey of human brain-derived cell lines, TC620 (oligodendroglioma) had the highest transduction efficiency with VP1-VLP. Up to 80% of the cells were expressing EGFP after transduction in vitro. In these studies, we added 0.3 ng/cell of VP1 protein containing 0.8 |[mu]|g of plasmid DNA to 5x104 cells. SK-N-SH, a human neuroblastoma cell line, and a population of primary normal human astrocytes also showed high transduction efficiencies following treatment with VP1-VLP. The rodent cell line NG108-15, a hybrid between a rat glioma and mouse neuroblastoma, and rat brain primary cells expressed EGFP after treatment with human VP1-VLP. These results demonstrate that VP1-VLP can transduce both human and rodent brain cells, at least in vitro. With the exception of one human prostate cell line (PC-3), significant VP1-VLP transduction was not observed in any non-brain-derived human or rodent cells studied including cell lines from kidney, liver, lung, skeletal muscle, and vascular endothelium. Thus, the VP1-VLP system from JCV may provide an efficient and selective delivery system for therapeutic genes to target specific cells in the brain.