897. Na,K-ATPase [beta]1-Mediated Selective Gene Transfer into Neurons

Neuron-selective gene transfer is an attractive therapeutic strategy for neurological disorders. Selective gene transfer requires high efficiency as well as tissue specificity of the target molecule employed. Selection of an optimal target molecule is critical. Here, we contrived the hybridoma library screening to identify optimal target molecules for neuron selective gene transfer using fiber mutant adenoviruses as targeting tools. We generated genetically modified adenoviruses incorporating Z33, an IgG Fc-binding motif from Staphylococcus protein A, at the fiber (Adv-FZ33 and Adv-FdZ). The Z33 vectors were capable of infecting cells through use of linked antibodies against surface antigen molecules.In this report, we established hybridoma clone 6E3 and mouse monoclonal antibody (mAb6E3) by this screening technique and identified the target antigen as Na,K-ATPase β1. Flow cytometry, chemiluminescent β-Gal reporter gene assays and immunocytochemistry using mAb6E3 and fiber mutant adenovirus documented efficient gene transfer into PC12 cells. This showed Na,K-ATPase β1 functions as the effective receptor for gene transfer into neurons. Immunohistochemistry images of rat spinal cord tissue showed that Na,K-ATPase β1 was expressed in neurons but not in oligodendrocytes or astrocytes. Experiments to transduce genes into neuron-glia cocultures using mAb6E3 and fiber mutant adenovirus resulted in neuron-selective gene transfer. These data indicate that Na,K-ATPase β1 is a good candidate molecule for neuron-selective gene transfer. Gene transfer via Na,K-ATPase β1 may be a useful strategy for treating neurological disorders, especially local disorders.