Efficient Gene Transfer into Retinal Cells by Modified Ad5/F35 Chimeric Adenovirus Vectors

Abstract

Abstract: : Purpose: In vitro and in vivo transduction efficiency of human retinoblastoma cells and murine retina using an adenoviral serotype 5 vector containing the fiber domain derived from adenovirus serotype 35 and the gene encoding green fluorescent protein (Ad5/F35-GFP) was compared to an Ad5-GFP vector. Methods: Y79 human retinoblastoma cells were incubated with either viral vector and the expression of the reporter protein was compared using quantitative fluorescence and fluorescent activated cell sorting. Mice were given a single sub-retinal injection of either Ad5-GFP or Ad5/F35-GFP. Eyes were enucleated at various times after injection for histopathologic examination. Results: Both vectors efficiently transduced the Y79 human retinoblastoma cells in vitro, however, the amount of the transgene expressed using Ad5/F35-GFP was more than six fold greater than that when Ad5-GFP was used. In vivo, Ad5/F35-GFP at doses as low as 10⁵ iu efficiently transduced cells in all layers of the retina including photoreceptors, neuronal cells, and müller cells as well as retinal pigment epithelial cells while Ad5-GFP efficiently transduced only retinal pigment epithelia cells. GFP expression persists at least one month after injection. Conclusion: Ad5/F35 chimeric vectors may be superior to Ad5 for gene therapy applications targeting the retina.

Keywords: gene transfer/gene therapy • photoreceptors • retina