Cell membrane-anchored anti-HIV single-chain antibodies and bifunctional inhibitors targeting the gp41 fusion protein: new strategies for HIV gene therapy.

Abstract

Emerging studies indicate that infusion of HIV-resistant cells could be an effective strategy to achieve a sterilizing or functional cure. We recently reported that glycosylphosphatidylinositol (GPI)-anchored nanobody or a fusion inhibitory peptide can render modified cells resistant to HIV-1 infection. In this study, we comprehensively characterized a panel of newly isolated HIV-1-neutralizing antibodies as GPI-anchored inhibitors. Fusion genes encoding the single-chain variable fragment (scFv) of 3BNC117, N6, PGT126, PGT128, 10E8, or 35O22 were constructed with a self-inactivating lentiviral vector, and they were efficiently expressed in the lipid raft sites of target cell membrane without affecting the expression of HIV-1 receptors (CD4, CCR5 and CXCR4). Significantly, transduced cells exhibited various degrees of resistance to cell-free HIV-1 infection and cell-associated HIV-1 transmission, as well as viral Env-mediated cell-cell fusion, with the cells modified by GPI-10E8 showing the most potent and broad anti-HIV activity. In mechanism, GPI-10E8 also interfered with the processing of viral Env in transduced cells and attenuated the infectivity of progeny viruses. By genetically linking 10E8 with a fusion inhibitor peptide, we subsequently designed a group of eight bifunctional constructs as cell membrane-based inhibitors, designated CMI01∼CMI08, which rendered cells completely resistant to HIV-1, HIV-2, and simian immunodeficiency virus (SIV). In human CD4+ T cells, GPI-10E8 and its bifunctional derivatives blocked both CCR5- and CXCR4-tropic HIV-1 isolates efficiently, and the modified cells displayed robust survival selection under HIV-1 infection. Therefore, our studies provide new strategies for generating HIV-resistant cells, which can be used alone or with other gene therapy approaches.

• Authors: Yue Chen, Hongliang Jin, Xiaoran Tang, Li Li, Xiuzhu Geng, Yuanmei Zhu, Huihui Chong, Yuxian He
• Journal: Emerging microbes & infections (Emerg Microbes Infect) Vol. 11 Issue 1 Pg. 30-49 (Dec 2022) ISSN: 2222-1751 [Electronic] United States
• PMID: 34821542 (Publication Type: Journal Article)

Chemical References

• Anti-HIV Agents
• Broadly Neutralizing Antibodies
• Glycosylphosphatidylinositols
• HIV Antibodies
• HIV Envelope Protein gp41
• HIV Fusion Inhibitors
• Peptide Fragments
• Receptors, HIV
• Single-Chain Antibodies

Topics

• Anti-HIV Agents (pharmacology)
• Broadly Neutralizing Antibodies (genetics, immunology)
• CD4-Positive T-Lymphocytes (virology)
• Cell Fusion
• Cell Line
• Genetic Therapy
• Glycosylphosphatidylinositols
• HIV Antibodies (genetics, immunology)
• HIV Envelope Protein gp41 (antagonists & inhibitors, immunology)
• HIV Fusion Inhibitors (pharmacology)
• HIV Infections (therapy, virology)
• HIV-1 (immunology, physiology)
• HIV-2 (immunology, physiology)
• Humans
• Membrane Microdomains
• Peptide Fragments (genetics, pharmacology)
• Receptors, HIV (metabolism)
• Simian Immunodeficiency Virus (immunology, physiology)
• Single-Chain Antibodies (genetics, immunology)
• Transgenes
• Viral Tropism