Establishment of HIV-1 resistance in CD4+ T cells by genome editing using zinc-finger nucleases

Abstract

Homozygosity for the naturally occurring Delta32 deletion in the HIV co-receptor CCR5 confers resistance to HIV-1 infection. We generated an HIV-resistant genotype de novo using engineered zinc-finger nucleases (ZFNs) to disrupt endogenous CCR5. Transient expression of CCR5 ZFNs permanently and specifically disrupted approximately 50% of CCR5 alleles in a pool of primary human CD4(+) T cells. Genetic disruption of CCR5 provided robust, stable and heritable protection against HIV-1 infection in vitro and in vivo in a NOG model of HIV infection. HIV-1-infected mice engrafted with ZFN-modified CD4(+) T cells had lower viral loads and higher CD4(+) T-cell counts than mice engrafted with wild-type CD4(+) T cells, consistent with the potential to reconstitute immune function in individuals with HIV/AIDS by maintenance of an HIV-resistant CD4(+) T-cell population. Thus adoptive transfer of ex vivo expanded CCR5 ZFN-modified autologous CD4(+) T cells in HIV patients is an attractive approach for the treatment of HIV-1 infection.

Generation of human TRIM5α mutants with high HIV-1 restriction activity

“…Therefore, it is likely that to succeed, a gene therapy approach for AIDS would need to disrupt viral replication either at entry or at immediate post-entry steps, before viral antigens are being synthesized. Interfering with the expression of the virus entry coreceptor CCR5, either by RNA interference 41,42 or by transfer of a zinc-finger nuclease 43 might achieve that goal, but the immunological consequences of completely disrupting CCR5 expression in human cells in vivo are unknown. Thus, expression of a TRIM5a-based …”

Viral surface glycoproteins, gp120 and gp41, as potential drug targets against HIV-1: Brief overview one quarter of a century past the approval of zidovudine, the first anti-retroviral drug

“…However, it is preferable to develop anti-HIV drugs targeting viral proteins (gp120 and gp41) rather than host cell molecules (CD4, CCR5 and CXCR4), because it is a concern that binding the cellular molecules might interfere with their normal functions, causing toxic or adverse effects. Despite this general truth, CCR5 has been intensively studied and validated as a target for HIV therapy [70,71] since the discovery that the homozygous Delta 32 deletion in CCR5 confers resistance to HIV-1 in normal survey people [72e74]. For a review about chemokine receptor antagonists please see Ref.…”

Progress and prospects: graft-versus-host disease

“…This will be possibly achieved through a combination of proper cytokine cocktails and more sophisticated gene transfer technologies, such as zinc-finger nucleases, enabling transgene integration in preselected genomic sites. 79,80 As the level of technological complexity increases, possibly enhancing the potency of T cell-based gene transfer, we will need to face the difficult issue of economic sustainability of gene therapy. Paradoxically, this will be probably achieved through the development of phase III clinical trials, able to demonstrate the long-term benefits of T cell-based gene therapy on morbidity, overall survival and quality of life of treated patients, thus enabling proper cost/benefit assessments.…”