Development of Lentiviral Vectors for HIV-1 Gene Therapy with Vif-Resistant APOBEC3G

Abstract

Strategies to control HIV-1 replication without antiviral therapy are needed to achieve a functional cure. To exploit the innate antiviral function of restriction factor cytidine deaminase APOBEC3G (A3G), we developed self-activating lentiviral vectors that efficiently deliver HIV-1 Vif-resistant mutant A3G-D128K to target cells. To circumvent APOBEC3 expression in virus-producing cells, which diminishes virus infectivity, a vector containing two overlapping fragments of A3G-D128K was designed that maintained the gene in an inactive form in the virus-producer cells. However, during transduction of target cells, retroviral recombination between the direct repeats reconstituted an active A3G-D128K in 89%–98% of transduced cells. Lentiviral vectors that expressed A3G-D128K transduced CD34+ hematopoietic stem and progenitor cells with a high efficiency (>30%). A3G-D128K expression in T cell lines CEM, CEMSS, and PM1 potently inhibited spreading infection of several HIV-1 subtypes by C-to-U deamination leading to lethal G-to-A hypermutation and inhibition of reverse transcription. SIVmac239 and HIV-2 were not inhibited, since their Vifs degraded A3G-D128K. A3G-D128K expression in CEM cells potently suppressed HIV-1 replication for >3.5 months without detectable resistant virus, suggesting a high genetic barrier for the emergence of A3G-D128K resistance. Because of this, A3G-D128K expression in HIV-1 target cells is a potential anti-HIV gene therapy approach that could be combined with other therapies for the treatment and functional cure of HIV-1 infection.

Power and Promise of Next-Generation Sequencing in Liquid Biopsies and Cancer Control

“…57 -60 This classification therapy led to the development of imatinib, a constitutive inhibitor of BCR-ABL kinase, for the treatment of leukemia. 61 -63…”

“…[57][58][59][60] This classification therapy led to the development of imatinib, a constitutive inhibitor of BCR-ABL kinase, for the treatment of leukemia. [61][62][63] At present, targeted therapeutic drugs include small molecule inhibitors and macromolecular monoclonal antibody drugs. For drugs with definite targets, it is necessary to use gene detection before they can be used (Figure 2).…”

Potential Utilization of APOBEC3-Mediated Mutagenesis for an HIV-1 Functional Cure

“…One potential strategy for controlling HIV-1 under cART-free conditions would be the use of Vif-resistant A3 proteins such as human A3G D128K proteins. Recently, Delviks-Frankenberry et al (2019) took a novel approach to control HIV-1 using self-activating lentiviral vectors that deliver the human A3G D128K gene to target cells. T cell lines in which the human A3G D128K gene was transduced by this system were shown to potently inhibit HIV-1 replication and suppress the emergence of resistant viruses against human A3G D128K proteins for >3.5 months.…”

APOBEC3s: history of an antiviral and mutagenic protein family

“…Cette approche fait intervenir un vecteur exprimant le mutant A3G-D128K, résistant à la dégradation par Vif, car incapable d'interagir avec cette dernière. Ce vecteur a permis d'empêcher in vitro la réplication virale dans des lignées T CD4 + pendant au moins trois mois sans apparition de virus résistants [368]. Parallèlement, l'activité des APOBEC3 peut constituer une piste thérapeutique dans les traitements anti-cancéreux, par exemple dans la voie DDR en cas d'utilisation d'inhibiteurs d'ATR (voir § « Propriétés antivirales des APOBEC3 : le cas du VIH-1 », page xx Q1) [59][60][61].…”