Abrogated cryptic activation of lentiviral transfer vectors.
Despite significant improvements in lentivirus (LV) vector-based gene therapy there are still several safety risks using LV vectors including the potential formation of replication-competent LV particles. To address this shortcoming, we constructed a novel and safer gene transfer system using modified SIN-based LV gene transfer vectors. Central to our approach is a conditional deletion of the Ψ packaging signal after integration in the target genome. Here we demonstrate that after transduction of target cells, conventional SIN-based LV transfer vectors can still be mobilized. However mobilization is rendered undetectable if transductions are followed by a Cre/loxP-mediated excision of Ψ. Thus conditional elimination of the packaging signal may represent another advance in increasing the safety of LV vectors for gene therapeutic treatment of chronic diseases.
Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
Ralf M
RM
Luche
Joerg
J
Enssle
Hans-Peter
HP
Kiem
D045744:Cell Line, Tumor; D005434:Flow Cytometry; D017353:Gene Deletion; D005814:Genes, Viral / Q000235:genetics*; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors / Q000235:genetics* / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D016086:Lentivirus / Q000235:genetics* / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D014161:Transduction, Genetic / Q000379:methods*; D019065:Virus Assembly / Q000235:genetics; D000097573:Red Fluorescent Protein
D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins; D000097573:Red Fluorescent Protein