title: Alpharetroviral vector-mediated gene therapy for X-CGD: functional correction and lack of aberrant splicing.
abstract: Comparative integrome analysis has revealed that the most neutral integration pattern among retroviruses is attributed to alpharetroviruses. We chose X-linked chronic granulomatous disease (X-CGD) as model to evaluate the potential of self-inactivating (SIN) alpharetroviral vectors for gene therapy of monogenic diseases. Therefore, we combined the alpharetroviral vector backbone with the elongation factor-1α short promoter, both considered to possess a low genotoxic profile, to drive transgene (gp91(phox)) expression. Following efficient transduction transgene expression was sustained and provided functional correction of the CGD phenotype in a cell line model at low vector copy number. Further analysis in a murine X-CGD transplantation model revealed gene-marking of bone marrow cells and oxidase positive granulocytes in peripheral blood. Transduction of human X-CGD CD34+ cells provided functional correction up to wild-type levels and long-term expression upon transplantation into a humanized mouse model. In contrast to lentiviral vectors, no aberrantly spliced transcripts containing cellular exons fused to alpharetroviral sequences were found in transduced cells, implying that the safety profile of alpharetroviral vectors may extend beyond their neutral integration profile. Taken together, this highlights the potential of this SIN alpharetroviral system as a platform for new candidate vectors for future gene therapy of hematopoietic disorders.
authors.affiliation: Institute for Biomedical Research, Georg-Speyer-Haus, Frankfurt, Germany.
authors.forename: Kerstin B
authors.initials: KB
authors.lastname: Kaufmann
authors.forename: Christian
authors.initials: C
authors.lastname: Brendel
authors.forename: Julia D
authors.initials: JD
authors.lastname: Suerth
authors.forename: Uta
authors.initials: U
authors.lastname: Mueller-Kuller
authors.forename: Linping
authors.initials: L
authors.lastname: Chen-Wichmann
authors.forename: Joachim
authors.initials: J
authors.lastname: Schwäble
authors.forename: Shweta
authors.initials: S
authors.lastname: Pahujani
authors.forename: Hana
authors.initials: H
authors.lastname: Kunkel
authors.forename: Axel
authors.initials: A
authors.lastname: Schambach
authors.forename: Christopher
authors.initials: C
authors.lastname: Baum
authors.forename: Manuel
authors.initials: M
authors.lastname: Grez
mesh_terms: D001355:Alpharetrovirus / Q000235:genetics*; D000818:Animals; D001854:Bone Marrow Cells; D045744:Cell Line, Tumor; D056915:DNA Copy Number Variations; D004195:Disease Models, Animal; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006098:Granulocytes; D006105:Granulomatous Disease, Chronic / Q000235:genetics / Q000628:therapy*; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases / Q000235:genetics / Q000378:metabolism; D010641:Phenotype; D012326:RNA Splicing; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014161:Transduction, Genetic; D019076:Transgenes
chemical_list: D008562:Membrane Glycoproteins; C056558:CYBB protein, human; D000074662:NADPH Oxidase 2; D019255:NADPH Oxidases