Sustained FXN expression in dorsal root ganglia from a nonreplicative genomic HSV-1 vector

Maria Ventosa, Zetang Wu and Filip Lim; The Journal of Gene Medicine, Accepted manuscript online: 17 OCT 2017 08:40PM EST DOI: 10.1002/jgm.2993

With the aim of developing a gene therapy for FA neuropathology, here we describe the construction and preliminary characterization of a high capacity nonreplicative genomic herpes simplex virus type 1 vector (H24B-FXNlac vector) carrying a reduced version of the human FXN genomic locus, comprising the 5 kb promoter and the FXN cDNA with the inclusion of intron 1.

We show that the transgene cassette contains the elements necessary to preserve physiological neuronal regulation of human FXN expression. Transduction of cultured fetal rat dorsal root ganglion neurons with the H24B-FXNlac vector results in sustained expression of human FXN transcripts and frataxin protein. Rat footpad inoculation with the H24B-FXNlac vector results in human FXN transgene delivery to the dorsal root ganglia, with expression persisting for at least 1 month.

Our results support the feasibility of using this vector for sustained neuronal expression of human frataxin for FA gene therapy.