Generation of HIV-resistant cells with a single-domain antibody: implications for HIV-1 gene therapy

Hongliang Jin,Yuxian He,Huihui Chong,Li Li,Yue Chen,Yuanmei Zhu,Xiaoran Tang

doi:10.1038/s41423-020-00627-y

Abstract

The cure or functional cure of the “Berlin patient” and “London patient” indicates that infusion of HIV-resistant cells could be a viable treatment strategy. Very recently, we genetically linked a short-peptide fusion inhibitor with a glycosylphosphatidylinositol (GPI) attachment signal, rendering modified cells fully resistant to HIV infection. In this study, GPI-anchored m36.4, a single-domain antibody (nanobody) targeting the coreceptor-binding site of gp120, was constructed with a lentiviral vector. We verified that m36.4 was efficiently expressed on the plasma membrane of transduced TZM-bl cells and targeted lipid raft sites without affecting the expression of HIV receptors (CD4, CCR5, and CXCR4). Significantly, TZM-bl cells expressing GPI-m36.4 were highly resistant to infection with divergent HIV-1 subtypes and potently blocked HIV-1 envelope-mediated cell-cell fusion and cell-cell viral transmission. Furthermore, we showed that GPI-m36.4-modified human CEMss-CCR5 cells were nonpermissive to both CCR5- and CXCR4-tropic HIV-1 isolates and displayed a strong survival advantage over unmodified cells. It was found that GPI-m36.4 could also impair HIV-1 Env processing and viral infectivity in transduced cells, underlying a multifaceted mechanism of antiviral action. In conclusion, our studies characterize m36.4 as a powerful nanobody that can generate HIV-resistant cells, offering a novel gene therapy approach that can be used alone or in combination.

Highlights

Active antiretroviral therapy (HAART), which employs multiple drugs in combination, can efficiently suppress HIV-1 replication, which has dramatically reduced the morbidity and mortality associated with AIDS and the risk of HIV-1 transmission.Highly active antiretroviral therapy (HAART) cannot eradicate latent virus, necessitating lifelong treatment that often causes cumulative toxicities and drug resistance[1,2]
Construction of lentiviral vectors for cell-surface expression of m36.4 through a GPI anchor To develop HIV-resistant cells as a gene therapy approach, fusion genes encoding the single-domain nanobody m36.4 or the scFv format of the control antibody FluIgG03 were constructed for cellsurface expression through a GPI anchoring approach
The recombinant lentiviruses were produced by cotransfecting HEK293T cells with the transfer vector, a packaging plasmid encoding Gag/Pol/Rev, and a plasmid encoding vesicular stomatitis virus G glycoprotein (VSV-G)

Summary

Introduction

Active antiretroviral therapy (HAART), which employs multiple drugs in combination, can efficiently suppress HIV-1 replication, which has dramatically reduced the morbidity and mortality associated with AIDS and the risk of HIV-1 transmission. HAART cannot eradicate latent virus, necessitating lifelong treatment that often causes cumulative toxicities and drug resistance[1,2]. Several vaccines designed to elicit broadly neutralizing antibodies (bNAbs) against HIV-1 have been developed, but they exhibit poor or no protective efficacy[3,4,5]. Similar to HAART, soluble bNAbs are not curative. The development of sterilizing or functional curative strategies has become a priority in the fight against HIV/AIDS

Methods

Results

Conclusion