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van Teijlingen NH, Helgers LC, Sarrami-Forooshani R, Zijlstra-Willems EM, van Hamme JL, Segui-Perez C, van Smoorenburg MY, Borgdorff H, van de Wijgert JH, van Leeuwen E, van der Post JA, Strijbis K, Ribeiro CM, Geijtenbeek TB. Vaginal bacterium Prevotella timonensis turns protective Langerhans cells into HIV-1 reservoirs for virus dissemination. EMBO J 2022; 41:e110629. [PMID: 35968812 PMCID: PMC9531304 DOI: 10.15252/embj.2022110629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 07/08/2022] [Accepted: 07/18/2022] [Indexed: 11/09/2022] Open
Abstract
Dysbiosis of vaginal microbiota is associated with increased HIV-1 acquisition, but the underlying cellular mechanisms remain unclear. Vaginal Langerhans cells (LCs) protect against mucosal HIV-1 infection via autophagy-mediated degradation of HIV-1. As LCs are in continuous contact with bacterial members of the vaginal microbiome, we investigated the impact of commensal and dysbiosis-associated vaginal (an)aerobic bacterial species on the antiviral function of LCs. Most of the tested bacteria did not affect the HIV-1 restrictive function of LCs. However, Prevotella timonensis induced a vast uptake of HIV-1 by vaginal LCs. Internalized virus remained infectious for days and uptake was unaffected by antiretroviral drugs. P. timonensis-exposed LCs efficiently transmitted HIV-1 to target cells both in vitro and ex vivo. Additionally, P. timonensis exposure enhanced uptake and transmission of the HIV-1 variants that establish infection after sexual transmission, the so-called Transmitted Founder variants. Our findings, therefore, suggest that P. timonensis might set the stage for enhanced HIV-1 susceptibility during vaginal dysbiosis and advocate targeted treatment of P. timonensis during bacterial vaginosis to limit HIV-1 infection.
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Affiliation(s)
- Nienke H van Teijlingen
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Leanne C Helgers
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Ramin Sarrami-Forooshani
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,ATMP Department, Breast Cancer Research Center, Motamed Cancer Institute, ACECR, Tehran, Iran
| | - Esther M Zijlstra-Willems
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - John L van Hamme
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Celia Segui-Perez
- Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Marleen Y van Smoorenburg
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Hanneke Borgdorff
- Amsterdam Institute for Global Health and Development (AIGHD), Amsterdam, The Netherlands
| | - Janneke Hhm van de Wijgert
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Elisabeth van Leeuwen
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Joris Am van der Post
- Department of Obstetrics and Gynecology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands
| | - Karin Strijbis
- Division Infectious Diseases and Immunology, Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - Carla Ms Ribeiro
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
| | - Teunis Bh Geijtenbeek
- Department of Experimental Immunology, Amsterdam UMC Location University of Amsterdam, Amsterdam, The Netherlands.,Amsterdam institute for Infection and Immunity, Amsterdam, The Netherlands
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2
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Targeted destabilization of the HIV-1 gp120-gp41 interface leads to convergent evolution with mutations in the V1V2, HR1 and HR2 domains. J Virol 2021; 95:e0053221. [PMID: 34586861 PMCID: PMC8610599 DOI: 10.1128/jvi.00532-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The HIV-1 envelope glycoprotein (Env) trimer is responsible for viral entry into target cells and is the sole target of neutralizing antibodies. The Env protein is therefore the focus of HIV-1 vaccine design. Env consists of two noncovalently linked subunits (gp120 and gp41) that form a trimer of heterodimers and this 6-subunit complex is metastable and conformationally flexible. Several approaches have been pursued to stabilize the Env trimer for vaccine purposes, which include structure-based design, high-throughput screening, and selection by mammalian cell display. Here, we employed directed virus evolution to improve Env trimer stability. Accordingly, we deliberately destabilized the Env gp120-gp41 interface by mutagenesis in the context of replicating HIV-1 LAI virus and virus evolution over time. We identified compensatory changes that pointed at convergent evolution, as they were largely restricted to specific Env regions, namely, the V1V2 domain of gp120 and the HR1 and HR2 domain of gp41. Specifically, S614G in V1V2 and Q567R in HR1 were frequently identified. Interestingly, the majority of the compensatory mutations were at distant locations from the original mutations and most likely strengthen intersubunit interactions. These results show how the virus can overcome Env instability and illuminate the regions that play a dominant role in Env stability. IMPORTANCE A successful HIV-1 vaccine most likely requires an envelope glycoprotein (Env) component, as Env is the only viral protein on the surface of the virus and the target for neutralizing antibodies. However, HIV Env is metastable and flexible because of the weak interactions between the Env subunits, complicating the generation of recombinant mimics of native Env. Here, we used directed viral evolution to study Env stability. We deliberately destabilized the interface between Env subunits and explored the capacity of the virus to repair trimer instability by evolution. We identified compensatory mutations that converged in specific Env locations: the apex and the trimer interface. Selected mutations enhanced the stability of recombinant soluble Env trimer proteins. These results provided clues on understanding the structural mechanisms involved in Env trimer stability, which can guide future immunogen design.
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3
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Wang Q, Su S, Xue J, Yu F, Pu J, Bi W, Xia S, Meng Y, Wang C, Yang W, Xu W, Zhu Y, Zheng Q, Qin C, Jiang S, Lu L. An amphipathic peptide targeting the gp41 cytoplasmic tail kills HIV-1 virions and infected cells. Sci Transl Med 2021; 12:12/546/eaaz2254. [PMID: 32493792 DOI: 10.1126/scitranslmed.aaz2254] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 04/28/2020] [Indexed: 12/26/2022]
Abstract
HIV-associated morbidity and mortality have markedly declined because of combinational antiretroviral therapy, but HIV readily mutates to develop drug resistance. Developing antivirals against previously undefined targets is essential to treat existing drug-resistant HIV strains. Some peptides derived from HIV-1 envelope glycoprotein (Env, gp120-gp41) have been shown to be effective in inhibiting HIV-1 infection. Therefore, we screened a peptide library from HIV-1 Env and identified a peptide from the cytoplasmic region, designated F9170, able to effectively inactivate HIV-1 virions and induce necrosis of HIV-1-infected cells, and reactivated latently infected cells. F9170 specifically targeted the conserved cytoplasmic tail of HIV-1 Env and effectively disrupted the integrity of the viral membrane. Short-term monoadministration of F9170 controlled viral loads to below the limit of detection in chronically SHIV-infected macaques. F9170 can enter the brain and lymph nodes, anatomic reservoirs for HIV latency. Therefore, F9170 shows promise as a drug candidate for HIV treatment.
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Affiliation(s)
- Qian Wang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Shan Su
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Jing Xue
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Re-emerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing 100021, China
| | - Fei Yu
- College of Life and Science, Hebei Agricultural University, Baoding 071001, China
| | - Jing Pu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Wenwen Bi
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Shuai Xia
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Yu Meng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Cong Wang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Wenqian Yang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Wei Xu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Yun Zhu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Qinwen Zheng
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China
| | - Chuan Qin
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Re-emerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing 100021, China.
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China. .,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology (MOE/NHC/CAMS), School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
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4
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Pu J, Dai Y, Wang Q, Lu L, Zhang J, Xu W, Xie L, Wang S, Yu F, He X, Jiang S. Rational Design of A Novel Small-Molecule HIV-1 Inactivator Targeting Both gp120 and gp41 of HIV-1. Front Pharmacol 2021; 11:613361. [PMID: 33569006 PMCID: PMC7868322 DOI: 10.3389/fphar.2020.613361] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 12/21/2020] [Indexed: 11/13/2022] Open
Abstract
Virus inactivator can inactivate cell-free virions without relying on their replication cycle, potentially reducing the impact of viral infection on cells. Previously, we successfully constructed a HIV-1 protein inactivator, 2DLT, by conjugating the D1D2 region of CD4 to the fusion inhibitor T1144 via a 35-amino acid linker. Therefore, it targets both the CD4 binding site in gp120 and NHR region in gp41. Considering that small-molecule agents have the advantages of fast production, low cost, good stability, and oral availability, we herein report the design of a new small-molecule HIV-1 inactivator, FD028, by conjugating FD016 (an analog of NBD-556, a gp120-CD4 binding inhibitor) with FD017 (an analog of 11d, an HIV-1 fusion inhibitor). The results showed that FD028 inactivated cell-free virions at a moderate nanomolar concentration by targeting both HIV-1 gp120 and gp41. Moreover, FD028 has broad-spectrum inhibition and inactivation activity against HIV-1 resistant strains and primary isolates of different subtypes without significant cytotoxicity. Therefore, FD028 has potential for further development as an HIV-1 inactivator-based therapeutic.
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Affiliation(s)
- Jing Pu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, United States
| | - Yu Dai
- Beijing Institute of Radiation Medicine, Beijing, China.,College of Life Sciences, Hebei Agricultural University, Baoding, China
| | - Qian Wang
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Junqi Zhang
- Medical Molecular Virology (MOE/NHC/CAMS), Department of Medical Microbiology and Parasitology, School of Basic Medical Sciences, Shanghai Medical College, Fudan University, Shanghai, China
| | - Wei Xu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Lan Xie
- Beijing Institute of Pharmacology and Toxicology, Beijing, China
| | - Shengqi Wang
- Beijing Institute of Radiation Medicine, Beijing, China
| | - Fei Yu
- College of Life Sciences, Hebei Agricultural University, Baoding, China
| | - Xiaoyang He
- Beijing Institute of Radiation Medicine, Beijing, China
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China.,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY, United States
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5
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Identification of an Antiretroviral Small Molecule That Appears To Be a Host-Targeting Inhibitor of HIV-1 Assembly. J Virol 2021; 95:JVI.00883-20. [PMID: 33148797 PMCID: PMC7925099 DOI: 10.1128/jvi.00883-20] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Accepted: 10/25/2020] [Indexed: 12/16/2022] Open
Abstract
Given the projected increase in multidrug-resistant HIV-1, there is an urgent need for development of antiretrovirals that act on virus life cycle stages not targeted by drugs currently in use. Host-targeting compounds are of particular interest because they can offer a high barrier to resistance. Here, we report identification of two related small molecules that inhibit HIV-1 late events, a part of the HIV-1 life cycle for which potent and specific inhibitors are lacking. This chemotype was discovered using cell-free protein synthesis and assembly systems that recapitulate intracellular host-catalyzed viral capsid assembly pathways. These compounds inhibit replication of HIV-1 in human T cell lines and peripheral blood mononuclear cells, and are effective against a primary isolate. They reduce virus production, likely by inhibiting a posttranslational step in HIV-1 Gag assembly. Notably, the compound colocalizes with HIV-1 Gag in situ; however, unexpectedly, selection experiments failed to identify compound-specific resistance mutations in gag or pol, even though known resistance mutations developed upon parallel nelfinavir selection. Thus, we hypothesized that instead of binding to Gag directly, these compounds localize to assembly intermediates, the intracellular multiprotein complexes containing Gag and host factors that form during immature HIV-1 capsid assembly. Indeed, imaging of infected cells shows compound colocalized with two host enzymes found in assembly intermediates, ABCE1 and DDX6, but not two host proteins found in other complexes. While the exact target and mechanism of action of this chemotype remain to be determined, our findings suggest that these compounds represent first-in-class, host-targeting inhibitors of intracellular events in HIV-1 assembly.IMPORTANCE The success of antiretroviral treatment for HIV-1 is at risk of being undermined by the growing problem of drug resistance. Thus, there is a need to identify antiretrovirals that act on viral life cycle stages not targeted by drugs in use, such as the events of HIV-1 Gag assembly. To address this gap, we developed a compound screen that recapitulates the intracellular events of HIV-1 assembly, including virus-host interactions that promote assembly. This effort led to the identification of a new chemotype that inhibits HIV-1 replication at nanomolar concentrations, likely by acting on assembly. This compound colocalized with Gag and two host enzymes that facilitate capsid assembly. However, resistance selection did not result in compound-specific mutations in gag, suggesting that the chemotype does not directly target Gag. We hypothesize that this chemotype represents a first-in-class inhibitor of virus production that acts by targeting a virus-host complex important for HIV-1 Gag assembly.
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6
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Pattnaik GP, Chakraborty H. Entry Inhibitors: Efficient Means to Block Viral Infection. J Membr Biol 2020; 253:425-444. [PMID: 32862236 PMCID: PMC7456447 DOI: 10.1007/s00232-020-00136-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/14/2020] [Indexed: 12/12/2022]
Abstract
The emerging and re-emerging viral infections are constant threats to human health and wellbeing. Several strategies have been explored to develop vaccines against these viral diseases. The main effort in the journey of development of vaccines is to neutralize the fusion protein using antibodies. However, significant efforts have been made in discovering peptides and small molecules that inhibit the fusion between virus and host cell, thereby inhibiting the entry of viruses. This class of inhibitors is called entry inhibitors, and they are extremely efficient in reducing viral infection as the entry of the virus is considered as the first step of infection. Nevertheless, these inhibitors are highly selective for a particular virus as antibody-based vaccines. The recent COVID-19 pandemic lets us ponder to shift our attention towards broad-spectrum antiviral agents from the so-called ‘one bug-one drug’ approach. This review discusses peptide and small molecule-based entry inhibitors against class I, II, and III viruses and sheds light on broad-spectrum antiviral agents.
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Affiliation(s)
| | - Hirak Chakraborty
- School of Chemistry, Sambalpur University, Jyoti Vihar, Burla, Odisha, 768 019, India. .,Centre of Excellence in Natural Products and Therapeutics, Sambalpur University, Jyoti Vihar, Burla, Odisha, 768 019, India.
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7
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Therapeutic Efficacy and Resistance Selection of a Lipopeptide Fusion Inhibitor in Simian Immunodeficiency Virus-Infected Rhesus Macaques. J Virol 2020; 94:JVI.00384-20. [PMID: 32404526 DOI: 10.1128/jvi.00384-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Accepted: 05/08/2020] [Indexed: 02/06/2023] Open
Abstract
We recently reported a group of lipopeptide-based membrane fusion inhibitors with potent antiviral activities against human immunodeficiency virus type 1 (HIV-1), HIV-2, and simian immunodeficiency virus (SIV). In this study, the in vivo therapeutic efficacy of such a lipopeptide, LP-52, was evaluated in rhesus macaques chronically infected with pathogenic SIVmac239. In a pilot study with one monkey, monotherapy with low-dose LP-52 rapidly reduced the plasma viral loads to below the limit of detection and maintained viral suppression during three rounds of structurally interrupted treatment. The therapeutic efficacy of LP-52 was further verified in four infected monkeys; however, three out of the monkeys had viral rebounds under the LP-52 therapy. We next focused on characterizing SIV mutants responsible for the in vivo resistance. Sequence analyses revealed that a V562A or V562M mutation in the N-terminal heptad repeat (NHR) and a E657G mutation in the C-terminal heptad repeat (CHR) of SIV gp41 conferred high resistance to LP-52 and cross-resistance to the peptide drug T20 and two newly designed lipopeptides (LP-80 and LP-83). Moreover, we showed that the resistance mutations greatly reduced the stability of diverse fusion inhibitors with the NHR site, and V562A or V562M in combination with E657G could significantly impair the functionality of viral envelopes (Envs) to mediate SIVmac239 infection and decrease the thermostability of viral six-helical bundle (6-HB) core structure. In conclusion, the present data have not only facilitated the development of novel anti-HIV drugs that target the membrane fusion step, but also help our understanding of the mechanism of viral evolution to develop drug resistance.IMPORTANCE The anti-HIV peptide drug T20 (enfuvirtide) is the only membrane fusion inhibitor available for treatment of viral infection; however, it exhibits relatively weak antiviral activity, short half-life, and a low genetic barrier to inducing drug resistance. Design of lipopeptide-based fusion inhibitors with extremely potent and broad antiviral activities against divergent HIV-1, HIV-2, and SIV isolates have provided drug candidates for clinical development. Here, we have verified a high therapeutic efficacy for the lipopeptide LP-52 in SIVmac239-infected rhesus monkeys. The resistance mutations selected in vivo have also been characterized, providing insights into the mechanism of action of newly designed fusion inhibitors with a membrane-anchoring property. For the first time, the data show that HIV-1 and SIV can share a similar genetic pathway to develop resistance, and that a lipopeptide fusion inhibitor could have a same resistance profile as its template peptide.
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8
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Ancy I, Sivanandam M, Kalaivani R, Kumaradhas P. Insights of inhibition mechanism of sifuvirtide and MT-sifuvirtide against wild and mutant HIV-1 envelope glycoprotein41: a molecular dynamics simulation and binding free energy study. MOLECULAR SIMULATION 2020. [DOI: 10.1080/08927022.2020.1716978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Iruthayaraj Ancy
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem, India
| | - Magudeeswaran Sivanandam
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem, India
| | - Raju Kalaivani
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem, India
| | - Poomani Kumaradhas
- Laboratory of Biocrystallography and Computational Molecular Biology, Department of Physics, Periyar University, Salem, India
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9
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Yu D, Su Y, Ding X, Zhu Y, Qin B, Chong H, Cui S, He Y. Structural and Functional Characterization of the Secondary Mutation N126K Selected by Various HIV-1 Fusion Inhibitors. Viruses 2020; 12:v12030326. [PMID: 32197300 PMCID: PMC7150849 DOI: 10.3390/v12030326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 02/15/2020] [Accepted: 03/03/2020] [Indexed: 01/15/2023] Open
Abstract
Peptides derived from the C-terminal heptad repeat (CHR) region of HIV-1 gp41 is potent viral membrane fusion inhibitors, such as the first clinically approved peptide drug T20 and a group of newly-designed peptides. The resistance profiles of various HIV-1 fusion inhibitors were previously characterized, and the secondary mutation N126K in the gp41 CHR was routinely identified during the in vitro and in vivo selections. In this study, the functional and structural relevance of the N126K mutation has been characterized from multiple angles. First, we show that a single N126K mutation across several HIV-1 isolates conferred mild to moderate cross-resistances. Second, the N126K mutation exerted different effects on Env-mediated HIV-1 entry and cell-cell fusion. Third, the N126K mutation did not interfere with the expression and processing of viral Env glycoproteins, but it disrupted the Asn126-based glycosylation site in gp41. Fourth, the N126K mutation was verified to enhance the thermal stability of 6-HB conformation. Fifth, we determined the crystal structure of a 6-HB bearing the N126K mutation, which revealed the interhelical and intrahelical interactions underlying the increased thermostability. Therefore, our data provide new information to understand the mechanism of HIV-1 gp41-mediated cell fusion and its resistance mode to viral fusion inhibitors.
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Affiliation(s)
- Danwei Yu
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Yang Su
- Department of Lab Medicine, Institute of Hematology, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin 300020, China
| | - Xiaohui Ding
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Yuanmei Zhu
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Bo Qin
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Huihui Chong
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Sheng Cui
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Yuxian He
- NHC Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
- Correspondence: ; Tel.: +86-10-67870275
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10
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The Tryptophan-Rich Motif of HIV-1 gp41 Can Interact with the N-Terminal Deep Pocket Site: New Insights into the Structure and Function of gp41 and Its Inhibitors. J Virol 2019; 94:JVI.01358-19. [PMID: 31619552 DOI: 10.1128/jvi.01358-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/09/2019] [Indexed: 11/20/2022] Open
Abstract
Refolding of the HIV-1 gp41 N- and C-terminal heptad repeats (NHR and CHR, respectively) into a six-helix bundle (6-HB) juxtaposes viral and cellular membranes for fusion. The CHR-derived peptide T20 is the only clinically approved viral fusion inhibitor and has potent anti-HIV activity; however, its mechanism of action is not fully understood. In this study, we surprisingly found that T20 disrupted the α-helical conformation of the NHR-derived peptide N54 through its C-terminal tryptophan-rich motif (TRM) and that synthetic short peptides containing the TRM sequence, TRM8 and TRM12, disrupted the N54 helix in a dose-dependent manner. Interestingly, TRM8 efficiently interfered with the secondary structures of three overlapping NHR peptides (N44, N38, and N28) and interacted with N28, which contains mainly the deep NHR pocket-forming sequence, with high affinity, suggesting that TRM targeted the NHR pocket site to mediate the disruption. Unlike TRM8, the short peptide corresponding to the pocket-binding domain (PBD) of the CHR helix had no such disruptive effect, and the CHR peptide C34 could form a stable 6-HB with the NHR helix; however, addition of the TRM to the C terminus of C34 resulted in a peptide (C46) that destroyed the NHR helix. Although the TRM peptides alone had no anti-HIV activity and could not block the formation of 6-HB conformation, substitution of the TRM for the PBD in C34 resulted in a mutant inhibitor (C34TRM) with high binding and inhibitory capacities. Combined, the present data inform a new mode of action of T20 and the structure-function relationship of gp41.IMPORTANCE The HIV-1 Env glycoprotein mediates membrane fusion and is conformationally labile. Despite extensive efforts, the structural property of the native fusion protein gp41 is largely unknown, and the mechanism of action of the gp41-derived fusion inhibitor T20 remains elusive. Here, we report that T20 and its C-terminal tryptophan-rich motif (TRM) can efficiently impair the conformation of the gp41 N-terminal heptad repeat (NHR) coiled coil by interacting with the deep NHR pocket site. The TRM sequence has been verified to possess the ability to replace the pocket-binding domain of C34, a fusion inhibitor peptide with high anti-HIV potency. Therefore, our studies have not only facilitated understanding of the mechanism of action of T20 and developed novel HIV-1 fusion inhibitors but also provided new insights into the structural property of the prefusion state of gp41.
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Smith AR, Weinstock MT, Siglin AE, Whitby FG, Francis JN, Hill CP, Eckert DM, Root MJ, Kay MS. Characterization of resistance to a potent D-peptide HIV entry inhibitor. Retrovirology 2019; 16:28. [PMID: 31640718 PMCID: PMC6805555 DOI: 10.1186/s12977-019-0489-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 10/03/2019] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND PIE12-trimer is a highly potent D-peptide HIV-1 entry inhibitor that broadly targets group M isolates. It specifically binds the three identical conserved hydrophobic pockets at the base of the gp41 N-trimer with sub-femtomolar affinity. This extremely high affinity for the transiently exposed gp41 trimer provides a reserve of binding energy (resistance capacitor) to prevent the viral resistance pathway of stepwise accumulation of modest affinity-disrupting mutations. Such modest mutations would not affect PIE12-trimer potency and therefore not confer a selective advantage. Viral passaging in the presence of escalating PIE12-trimer concentrations ultimately selected for PIE12-trimer resistant populations, but required an extremely extended timeframe (> 1 year) in comparison to other entry inhibitors. Eventually, HIV developed resistance to PIE12-trimer by mutating Q577 in the gp41 pocket. RESULTS Using deep sequence analysis, we identified three mutations at Q577 (R, N and K) in our two PIE12-trimer resistant pools. Each point mutant is capable of conferring the majority of PIE12-trimer resistance seen in the polyclonal pools. Surface plasmon resonance studies demonstrated substantial affinity loss between PIE12-trimer and the Q577R-mutated gp41 pocket. A high-resolution X-ray crystal structure of PIE12 bound to the Q577R pocket revealed the loss of two hydrogen bonds, the repositioning of neighboring residues, and a small decrease in buried surface area. The Q577 mutations in an NL4-3 backbone decreased viral growth rates. Fitness was ultimately rescued in resistant viral pools by a suite of compensatory mutations in gp120 and gp41, of which we identified seven candidates from our sequencing data. CONCLUSIONS These data show that PIE12-trimer exhibits a high barrier to resistance, as extended passaging was required to develop resistant virus with normal growth rates. The primary resistance mutation, Q577R/N/K, found in the conserved gp41 pocket, substantially decreases inhibitor affinity but also damages viral fitness, and candidate compensatory mutations in gp160 have been identified.
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Affiliation(s)
- Amanda R. Smith
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
| | - Matthew T. Weinstock
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
| | - Amanda E. Siglin
- 0000 0001 2166 5843grid.265008.9Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107 USA
| | - Frank G. Whitby
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
| | - J. Nicholas Francis
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
| | - Christopher P. Hill
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
| | - Debra M. Eckert
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
| | - Michael J. Root
- 0000 0001 2166 5843grid.265008.9Department of Biochemistry and Molecular Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA 19107 USA
| | - Michael S. Kay
- 0000 0001 2193 0096grid.223827.eDepartment of Biochemistry, University of Utah School of Medicine, Salt Lake City, UT 84112 USA
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Conserved Residue Asn-145 in the C-Terminal Heptad Repeat Region of HIV-1 gp41 is Critical for Viral Fusion and Regulates the Antiviral Activity of Fusion Inhibitors. Viruses 2019; 11:v11070609. [PMID: 31277353 PMCID: PMC6669600 DOI: 10.3390/v11070609] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 06/29/2019] [Accepted: 06/29/2019] [Indexed: 12/21/2022] Open
Abstract
Entry of HIV-1 into target cells is mediated by its envelope (Env) glycoprotein composed of the receptor binding subunit gp120 and the fusion protein gp41. Refolding of the gp41 N- and C-terminal heptad repeats (NHR and CHR) into a six-helix bundle (6-HB) conformation drives the viral and cellular membranes in close apposition and generates huge amounts of energy to overcome the kinetic barrier leading to membrane fusion. In this study, we focused on characterizing the structural and functional properties of a single Asn-145 residue, which locates at the middle CHR site of gp41 and is extremely conserved among all the HIV-1, HIV-2, and simian immunodeficiency virus (SIV) isolates. By mutational analysis, we found that Asn-145 plays critical roles for Env-mediated cell-cell fusion and HIV-1 entry. As determined by circular dichroism (CD) spectroscopy and isothermal titration calorimetry (ITC), the substitution of Asn-145 with alanine (N145A) severely impaired the interactions between the NHR and CHR helices. Asn-145 was also verified to be important for the antiviral activity of CHR-derived peptide fusion inhibitors and served as a turn-point for the inhibitory potency. Intriguingly, Asn-145 could regulate the functionality of the M-T hook structure at the N-terminus of the inhibitors and displayed comparable activities with the C-terminal IDL anchor. Crystallographic studies further demonstrated the importance of Asn-145-mediated interhelical and intrahelical interactions in the 6-HB structure. Combined, the present results have provided valuable information for the structure-function relationship of HIV-1 gp41 and the structure-activity relationship of gp41-dependent fusion inhibitors.
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Su S, Rasquinha G, Du L, Wang Q, Xu W, Li W, Lu L, Jiang S. A Peptide-Based HIV-1 Fusion Inhibitor with Two Tail-Anchors and Palmitic Acid Exhibits Substantially Improved In Vitro and Ex Vivo Anti-HIV-1 Activity and Prolonged In Vivo Half-Life. Molecules 2019; 24:molecules24061134. [PMID: 30901967 PMCID: PMC6470885 DOI: 10.3390/molecules24061134] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 03/19/2019] [Accepted: 03/19/2019] [Indexed: 01/29/2023] Open
Abstract
Enfuvirtide (T20) is the first U.S. FDA-approved HIV fusion inhibitor-based anti-HIV drug. Its clinical application is limited because of its low potency and short half-life. We previously reported that peptide HP23-E6-IDL, containing both N- and C-terminal anchor-tails, exhibited stronger potency and a better resistance profile than T20. Here we designed an analogous peptide, YIK, by introducing a mutation, T639I, and then a lipopeptide, YIK-C16, by adding palmitic acid (C16) at the C-terminus of YIK. We found that YIK-C16 was 4.4- and 3.6-fold more potent than HP23-E6-IDL and YIK against HIV-1IIIB infection and 13.3- and 10.5-fold more effective than HP23-E6-IDL and YIK against HIV-1Bal infection, respectively. Consistently, the ex vivo anti-HIV-1IIIB activity, as determined by the highest dilution-fold of the serum causing 50% inhibition of HIV-1 infection, of YIK-C16 in the sera of pretreated mice was remarkably higher than that of YIK or HP23-E6-IDL. The serum half-life (t1/2 = 5.9 h) of YIK-C16 was also significantly longer than that of YIK (t1/2 = 1.3 h) and HP23-E6-IDL (t1/2 = 1.0 h). These results suggest that the lipopeptide YIK-C16 shows promise for further development as a new anti-HIV drug with improved anti-HIV-1 activity and a prolonged half-life.
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Affiliation(s)
- Shan Su
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
| | - Giselle Rasquinha
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
| | - Lanying Du
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
| | - Qian Wang
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Wei Xu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Weihua Li
- NHC Key Laboratory of Reproduction Regulation, Shanghai Institute of Planned Parenthood Research, Fudan University, Shanghai 200032, China.
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences and Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
- NHC Key Laboratory of Reproduction Regulation, Shanghai Institute of Planned Parenthood Research, Fudan University, Shanghai 200032, China.
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14
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Chong H, Xue J, Zhu Y, Cong Z, Chen T, Wei Q, Qin C, He Y. Monotherapy with a low-dose lipopeptide HIV fusion inhibitor maintains long-term viral suppression in rhesus macaques. PLoS Pathog 2019; 15:e1007552. [PMID: 30716118 PMCID: PMC6375636 DOI: 10.1371/journal.ppat.1007552] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 02/14/2019] [Accepted: 01/02/2019] [Indexed: 11/23/2022] Open
Abstract
Combination antiretroviral therapy (cART) dramatically improves survival of HIV-infected patients, but lifelong treatment can ultimately result in cumulative toxicities and drug resistance, thus necessitating the development of new drugs with significantly improved pharmaceutical profiles. We recently found that the fusion inhibitor T-20 (enfuvirtide)-based lipopeptides possess dramatically increased anti-HIV activity. Herein, a group of novel lipopeptides were designed with different lengths of fatty acids, identifying a stearic acid-modified lipopeptide (LP-80) with the most potent anti-HIV activity. It inhibited a large panel of divergent HIV subtypes with a mean IC50 in the extremely low picomolar range, being > 5,300-fold more active than T-20 and the neutralizing antibody VRC01. It also sustained the potent activity against T-20-resistant mutants and exhibited very high therapeutic selectivity index. Pharmacokinetics of LP-80 in rats and monkeys verified its potent and long-acting anti-HIV activity. In the monkey, subcutaneous administration of 3 mg/kg LP-80 yielded serum concentrations of 1,147 ng/ml after injection 72 h and 9 ng/ml after injection 168 h (7 days), equivalent to 42,062- and 330-fold higher than the measured IC50 value. In SHIV infected rhesus macaques, a single low-dose LP-80 (3 mg/kg) sharply reduced viral loads to below the limitation of detection, and twice-weekly monotherapy could maintain long-term viral suppression. T-20 is the only clinically approved viral fusion inhibitor, which is used in combination therapy for HIV-1 infection; however, it exhibits relatively low antiviral activity and easily induces drug resistance. Here we report a lipopeptide fusion inhibitor termed LP-80, which exhibits the most potent activity in inhibiting divergent HIV-1 subtypes. Especially, LP-80 has extremely potent and long-acting therapeutic efficacy with very low cytotoxicity, making it an ideal drug candidate for clinical use. Furthermore, LP-80 and its truncated versions can be used as important probes for exploiting the mechanisms of viral fusion and inhibition.
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Affiliation(s)
- Huihui Chong
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jing Xue
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Remerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China
| | - Yuanmei Zhu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Zhe Cong
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Remerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China
| | - Ting Chen
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Remerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China
| | - Qiang Wei
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Remerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China
| | - Chuan Qin
- Key Laboratory of Human Disease Comparative Medicine, Chinese Ministry of Health, Beijing Key Laboratory for Animal Models of Emerging and Remerging Infectious Diseases, Institute of Laboratory Animal Science, Chinese Academy of Medical Sciences and Comparative Medicine Center, Peking Union Medical College, Beijing, China
- * E-mail: (CQ); (YH)
| | - Yuxian He
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- * E-mail: (CQ); (YH)
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15
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Eggink D, Bontjer I, de Taeye SW, Langedijk JPM, Berkhout B, Sanders RW. HIV-1 anchor inhibitors and membrane fusion inhibitors target distinct but overlapping steps in virus entry. J Biol Chem 2019; 294:5736-5746. [PMID: 30696772 PMCID: PMC6463712 DOI: 10.1074/jbc.ra119.007360] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 01/25/2019] [Indexed: 12/03/2022] Open
Abstract
HIV-1 entry into cells is mediated by the envelope glycoprotein (Env) and represents an attractive target for therapeutic intervention. Two drugs that inhibit HIV entry are approved for clinical use: the membrane fusion-inhibitor T20 (Fuzeon, enfuvirtide) and the C-C chemokine receptor type 5 (CCR5) blocker maraviroc (Selzentry). Another class of entry inhibitors supposedly target the fusion peptide (FP) and are termed anchor inhibitors. These include the VIRIP peptide and VIRIP derivatives such as VIR165, VIR353, and VIR576. Here, we investigated the mechanism of inhibition by VIR165. We show that substitutions within the FP modulate sensitivity to VIR165, consistent with the FP being the drug target. Our results also revealed that VIR165 acts during an intermediate post-CD4–binding entry step that is overlapping but not identical to the step inhibited by fusion inhibitors such as T20. We found that some but not all resistance mutations to heptad repeat 2 (HR2)-targeting fusion inhibitors can provide cross-resistance to VIR165. In contrast, resistance mutations in the HR1-binding site for the fusion inhibitors did not cause cross-resistance to VIR165. However, Env with mutations located outside this binding site and thought to affect fusion kinetics, exhibited decreased sensitivity to VIR165. Although we found a strong correlation between Env stability and resistance to HR2-based fusion inhibitors, such correlation was not observed for Env stability and VIR165 resistance. We conclude that VIRIP analogs target the FP during an intermediate, post-CD4–binding entry step that overlaps with but is distinct from the step(s) inhibited by HR2-based fusion inhibitors.
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Affiliation(s)
- Dirk Eggink
- From the Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers (Amsterdam UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Ilja Bontjer
- From the Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers (Amsterdam UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Steven W de Taeye
- From the Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers (Amsterdam UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | | | - Ben Berkhout
- From the Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers (Amsterdam UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - Rogier W Sanders
- From the Laboratory of Experimental Virology, Department of Medical Microbiology, Amsterdam University Medical Centers (Amsterdam UMC), Location AMC, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands; the Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York 10065.
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16
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Falkenhagen A, Joshi S. HIV Entry and Its Inhibition by Bifunctional Antiviral Proteins. MOLECULAR THERAPY-NUCLEIC ACIDS 2018; 13:347-364. [PMID: 30340139 PMCID: PMC6197789 DOI: 10.1016/j.omtn.2018.09.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 09/05/2018] [Accepted: 09/05/2018] [Indexed: 12/14/2022]
Abstract
HIV entry is a highly specific and time-sensitive process that can be divided into receptor binding, coreceptor binding, and membrane fusion. Bifunctional antiviral proteins (bAVPs) exploit the multi-step nature of the HIV entry process by binding to two different extracellular targets. They are generated by expressing a fusion protein containing two entry inhibitors with a flexible linker. The resulting fusion proteins exhibit exceptional neutralization potency and broad cross-clade inhibition. In this review, we summarize the HIV entry process and provide an overview of the design, antiviral potency, and methods of delivery of bAVPs. Additionally, we discuss the advantages and limitations of bAVPs for HIV prevention and treatment.
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Affiliation(s)
- Alexander Falkenhagen
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 3E2, Canada
| | - Sadhna Joshi
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada; Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 3E2, Canada.
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17
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Reduced Susceptibility to VIRIP-Based HIV-1 Entry Inhibitors Has a High Genetic Barrier and Severe Fitness Costs. J Virol 2018; 92:JVI.00733-18. [PMID: 29925662 DOI: 10.1128/jvi.00733-18] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 06/14/2018] [Indexed: 02/05/2023] Open
Abstract
VIRIP has been identified as natural HIV-1 inhibitor targeting the gp41 fusion peptide. An optimized analogue (VIR-576) was effective in a phase I/II clinical trial and initial studies showed that HIV-1 resistance to VIRIP-based inhibitors has a high genetic barrier. Partially resistant CXCR4 (X4)-tropic HIV-1 NL4-3 variants could be obtained, however, after more than 15 months of passaging in MT-4 cells in the presence of another derivative (VIR-353). Sequence analyses identified the accumulation of seven mutations across the HIV-1 envelope glycoprotein but outside the gp41 fusion peptide. The authors suggested that the three initial alterations conferred resistance, while subsequent changes restored viral fitness. Here, we introduced these mutations individually and in combination into X4- and CCR5 (R5)-tropic HIV-1 constructs and determined their impact on VIR-353 and VIR-576 susceptibility, viral infectivity, replication fitness, and fusogenicity. We found that essentially all seven mutations contribute to reduced susceptibility to VIRIP-based inhibitors. HIV-1 constructs containing ≥4 changes were substantially more resistant to both VIRIP-based inhibitors and the VRC34.01 antibody targeting the fusion peptide. However, they were also much less infectious and fusogenic than those harboring only the three initial alterations. Furthermore, the additional changes attenuated rather than rescued HIV-1 replication in primary human cells. Thus, the genetic barrier to HIV-1 resistance against VIRIP-based inhibitors is higher than previously suggested, and mutations reducing viral susceptibility come at a severe fitness cost that was not rescued during long-term cell culture passage.IMPORTANCE Many viral pathogens are critically dependent on fusion peptides (FPs) that are inserted into the cellular membrane for infection. Initially, it was thought that FPs cannot be targeted for therapy because they are hardly accessible. However, an optimized derivative (VIR-576) of an endogenous fragment of α1-antitrypsin, named VIRIP, targeting the gp41 FP reduced viral loads in HIV-1-infected individuals. Characterization of HIV-1 variants selected during long-term cell-culture passage in the presence of a VIRIP derivative suggested that just three mutations in the HIV-1 Env protein might be sufficient for VIRIP resistance and that four subsequent changes restored viral fitness. Here, we show that all seven mutations contribute to reduced viral susceptibility to VIRIP-based inhibitors and demonstrate that the additional changes strongly impair rather than rescue HIV-1 infectivity, fusogenicity, and replication fitness. High genetic barrier to resistance and severe fitness cost support further clinical development of this class of antiviral agents.
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18
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HIV-1 gp41 Residues Modulate CD4-Induced Conformational Changes in the Envelope Glycoprotein and Evolution of a Relaxed Conformation of gp120. J Virol 2018; 92:JVI.00583-18. [PMID: 29875245 DOI: 10.1128/jvi.00583-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Accepted: 05/24/2018] [Indexed: 01/09/2023] Open
Abstract
Entry of human immunodeficiency virus type 1 (HIV-1) into host cells is mediated by conformational changes in the envelope glycoprotein (Env) that are triggered by Env binding to cellular CD4 and chemokine receptors. These conformational changes involve the opening of the gp120 surface subunit, exposure of the fusion peptide in the gp41 transmembrane subunit, and refolding of the gp41 N- and C-terminal heptad repeat regions (HR1 and HR2) first into an extended prehairpin intermediate and then into a compact 6-helix bundle (6HB) that facilitates fusion between viral and host cell membranes. Previously, we reported that Envs resistant to HR1 peptide fusion inhibitors acquired key resistance mutations in either HR1 or HR2 that increased 6HB stability. Here, we identify residues in HR1 that contribute not only to fusion inhibitor resistance and 6HB stability but also to reduced reactivity to CD4-induced conformational changes that lead to 6HB formation. While all Envs show increased neutralization sensitivity to mimetic CD4 (mCD4), Envs with either the E560K or Q577R HR1 mutation reduced conformational reactivity to CD4 that resisted viral inactivation and triggering to the 6HB. Using a panel of monoclonal antibodies (mAbs), we further determined that Envs from both HR1 and HR2 resistance pathways exhibit a relaxed trimer conformation due to gp120 adaptive mutations in different regions of Env that segregate by resistance pathway. These findings highlight regions of cross talk between gp120 and gp41 and identify HR1 residues that play important roles in regulating CD4-induced conformational changes in Env.IMPORTANCE Binding of the HIV envelope glycoprotein (Env) to cellular CD4 and chemokine receptors triggers conformational changes in Env that mediate virus entry, but premature triggering of Env conformational changes leads to virus inactivation. Currently, we have a limited understanding of the network of residues that regulate Env conformational changes. Here, we identify residues in HR1 of gp41 that modulate conformational changes in response to gp120 binding to CD4 and show that the mutations in HR1 and HR2 that confer resistance to fusion inhibitors are associated with gp120 mutations in different regions of Env that confer a more open conformation. These findings contribute to our understanding of the regulation of Env conformational changes and efforts to design new entry inhibitors and stable Env vaccine immunogens.
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19
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A Novel gp41-Binding Adnectin with Potent Anti-HIV Activity Is Highly Synergistic when Linked to a CD4-Binding Adnectin. J Virol 2018; 92:JVI.00421-18. [PMID: 29743355 DOI: 10.1128/jvi.00421-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2018] [Accepted: 04/26/2018] [Indexed: 12/27/2022] Open
Abstract
The N17 region of gp41 in HIV-1 is the most conserved region in gp160. mRNA selection technologies were used to identify an adnectin that binds to this region and inhibits gp41-induced membrane fusion. Additional selection conditions were used to optimize the adnectin to greater potency (5.4 ± 2.6 nM) against HIV-1 and improved binding affinity for an N17-containing helical trimer (0.8 ± 0.4 nM). Resistance to this adnectin mapped to a single Glu-to-Arg change within the N17 coding region. The optimized adnectin (6200_A08) exhibited high potency and broad-spectrum activity against 123 envelope proteins and multiple clinical virus isolates, although certain envelope proteins did exhibit reduced susceptibility to 6200_A08 alone. The reduced potency could not be correlated with sequence changes in the target region and was thought to be the result of faster kinetics of fusion mediated by these envelope proteins. Optimized linkage of 6200_A08 with a previously characterized adnectin targeting CD4 produced a highly synergistic molecule, with the potency of the tandem molecule measured at 37 ± 1 pM. In addition, these tandem molecules now exhibited few potency differences against the same panel of envelope proteins with reduced susceptibility to 6200_A08 alone, providing evidence that they did not have intrinsic resistance to 6200_A08 and that coupling 6200_A08 with the anti-CD4 adnectin may provide a higher effective on rate for gp41 target engagement.IMPORTANCE There continue to be significant unmet medical needs for patients with HIV-1 infection. One way to improve adherence and decrease the likelihood of drug-drug interactions in HIV-1-infected patients is through the development of long-acting biologic inhibitors. This study describes the development and properties of an adnectin molecule that targets the most conserved region of the gp41 protein and inhibits HIV-1 with good potency. Moreover, when fused to a similar adnectin targeted to the human CD4 protein, the receptor for HIV-1, significant synergies in potency and efficacy are observed. These inhibitors are part of an effort to develop a larger biologic molecule that functions as a long-acting self-administered regimen for patients with HIV-1 infection.
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20
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Yu D, Ding X, Liu Z, Wu X, Zhu Y, Wei H, Chong H, Cui S, He Y. Molecular mechanism of HIV-1 resistance to sifuvirtide, a clinical trial-approved membrane fusion inhibitor. J Biol Chem 2018; 293:12703-12718. [PMID: 29929981 DOI: 10.1074/jbc.ra118.003538] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 06/13/2018] [Indexed: 12/25/2022] Open
Abstract
Host cell infection with HIV-1 requires fusion of viral and cell membranes. Sifuvirtide (SFT) is a peptide-based HIV-1 fusion inhibitor approved for phase III clinical trials in China. Here, we focused on characterizing HIV-1 variants highly resistant to SFT to gain insight into the molecular resistance mechanism. Three primary substitutions (V38A, A47I, and Q52R) located at the inhibitor-binding site of HIV-1's envelope protein (Env) and one secondary substitution (N126K) located at the C-terminal heptad repeat region of the viral protein gp41, which is part of the envelope, conferred high SFT resistance and cross-resistance to the anti-HIV-1 drug T20 and the template peptide C34. Interestingly, SFT's resistance profile could be dramatically improved with an M-T hook structure-modified SFT (MTSFT) and with short-peptide inhibitors that mainly target the gp41 pocket (2P23 and its lipid derivative LP-19). We found that the V38A and Q52R substitutions reduce the binding stabilities of SFT, C34, and MTSFT, but they had no effect on the binding of 2P23 and LP-19; in sharp contrast, the A47I substitution enhanced fusion inhibitor binding. Furthermore, the primary resistance substitutions impaired Env-mediated membrane fusion and cell entry and changed the conformation of the gp41 core structure. Importantly, whereas the V38A and Q52R substitutions disrupted the N-terminal helix of gp41, a single A47I substitution greatly enhanced its thermostability. Taken together, our results provide crucial structural insights into the mechanism of HIV-1 resistance to gp41-dependent fusion inhibitors, which may inform the development of additional anti-HIV drugs.
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Affiliation(s)
- Danwei Yu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Xiaohui Ding
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Zixuan Liu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Xiyuan Wu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Yuanmei Zhu
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Huanmian Wei
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Huihui Chong
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Sheng Cui
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China
| | - Yuxian He
- MOH Key Laboratory of Systems Biology of Pathogens, Institute of Pathogen Biology, Beijing 100730, China; Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China.
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Mechanism of HIV-1 Resistance to an Electronically Constrained α-Helical Peptide Membrane Fusion Inhibitor. J Virol 2018; 92:JVI.02044-17. [PMID: 29321334 DOI: 10.1128/jvi.02044-17] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2017] [Accepted: 01/02/2018] [Indexed: 11/20/2022] Open
Abstract
SC29EK is an electronically constrained α-helical peptide HIV-1 fusion inhibitor that is highly effective against both wild-type and enfuvirtide (T20)-resistant viruses. In this study, we focused on investigating the mechanism of HIV-1 resistance to SC29EK by two approaches. First, SC29EK-escaping HIV-1 variants were selected and characterized. Three mutant viruses, which possessed two (N43K/E49A) or three (Q39R/N43K/N126K and N43K/E49A/N126K) amino acid substitutions in the N- and C-terminal repeat regions of gp41 were identified as conferring high resistance to SC29EK and cross-resistance to the first-generation (T20 and C34) and newly designed (sifuvirtide, MT-SC29EK, and 2P23) fusion inhibitors. The resistance mutations could reduce the binding stability of SC29EK, impair viral Env-mediated cell fusion and entry, and change the conformation of the gp41 core structure. Further, we determined the crystal structure of SC29EK in complex with a target mimic peptide, which revealed the critical intra- and interhelical interactions underlying the mode of action of SC29EK and the genetic pathway to HIV-1 resistance. Taken together, the present data provide new insights into the structure and function of gp41 and the structure-activity relationship (SAR) of viral fusion inhibitors.IMPORTANCE T20 is the only membrane fusion inhibitor available for treatment of viral infection, but it has relatively low anti-HIV activity and genetic barriers for resistance, thus calling for new drugs blocking the viral fusion process. As an electronically constrained α-helical peptide, SC29EK is highly potent against both wild-type and T20-resistant HIV-1 strains. Here, we report the characterization of HIV-1 variants resistant to SC29EK and the crystal structure of SC29EK. The key mutations mediating high resistance to SC29EK and cross-resistance to the first and new generations of fusion inhibitors as well as the underlying mechanisms were identified. The crystal structure of SC29EK bound to a target mimic peptide further revealed its action mode and genetic pathway to inducing resistance. Hence, our data have shed new lights on the mechanisms of HIV-1 fusion and its inhibition.
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Zhang X, Zhu Y, Hu H, Zhang S, Wang P, Chong H, He J, Wang X, He Y. Structural Insights into the Mechanisms of Action of Short-Peptide HIV-1 Fusion Inhibitors Targeting the Gp41 Pocket. Front Cell Infect Microbiol 2018. [PMID: 29535974 PMCID: PMC5834435 DOI: 10.3389/fcimb.2018.00051] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The deep hydrophobic pocket of HIV-1 gp41 has been considered a drug target, but short-peptides targeting this site usually lack potent antiviral activity. By applying the M-T hook structure, we previously generated highly potent short-peptide fusion inhibitors that specifically targeted the pocket site, such as MT-SC22EK, HP23L, and LP-11. Here, the crystal structures of HP23L and LP-11 bound to the target mimic peptide N36 demonstrated the critical intrahelical and interhelical interactions, especially verifying that the hook-like conformation was finely adopted while the methionine residue was replaced by the oxidation-less prone residue leucine, and that addition of an extra glutamic acid significantly enhanced the binding and inhibitory activities. The structure of HP23L bound to N36 with two mutations (E49K and L57R) revealed the critical residues and motifs mediating drug resistance and provided new insights into the mechanism of action of inhibitors. Therefore, the present data help our understanding for the structure-activity relationship (SAR) of HIV-1 fusion inhibitors and facilitate the development of novel antiviral drugs.
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Affiliation(s)
- Xiujuan Zhang
- College of Life Sciences and Bioengineering, School of Science, Beijing Jiaotong University, Beijing, China.,Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yuanmei Zhu
- Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Hao Hu
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Senyan Zhang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Pengfei Wang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Huihui Chong
- Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jinsheng He
- College of Life Sciences and Bioengineering, School of Science, Beijing Jiaotong University, Beijing, China
| | - Xinquan Wang
- Ministry of Education Key Laboratory of Protein Science, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing, China
| | - Yuxian He
- Institute of Pathogen Biology and Center for AIDS Research, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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23
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Su S, Ma Z, Hua C, Li W, Lu L, Jiang S. Adding an Artificial Tail-Anchor to a Peptide-Based HIV-1 Fusion Inhibitor for Improvement of Its Potency and Resistance Profile. Molecules 2017; 22:molecules22111996. [PMID: 29156603 PMCID: PMC6150406 DOI: 10.3390/molecules22111996] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Revised: 11/10/2017] [Accepted: 11/16/2017] [Indexed: 11/16/2022] Open
Abstract
Peptides derived from the C-terminal heptad repeat (CHR) of human immunodeficiency virus type 1 (HIV-1) envelope protein transmembrane subunit gp41, such as T20 (enfuvirtide), can bind to the N-terminal heptad repeat (NHR) of gp41 and block six-helix bundle (6-HB) formation, thus inhibiting HIV-1 fusion with the target cell. However, clinical application of T20 is limited because of its low potency and genetic barrier to resistance. HP23, the shortest CHR peptide, exhibits better anti-HIV-1 activity than T20, but the HIV-1 strains with E49K mutations in gp41 will become resistant to it. Here, we modified HP23 by extending its C-terminal sequence using six amino acid residues (E6) and adding IDL (Ile-Asp-Leu) to the C-terminus of E6, which is expected to bind to the shallow pocket in the gp41 NHR N-terminal region. The newly designed peptide, designated HP23-E6-IDL, was about 2- to 16-fold more potent than HP23 against a broad spectrum of HIV-1 strains and more than 12-fold more effective against HIV-1 mutants resistant to HP23. These findings suggest that addition of an anchor-tail to the C-terminus of a CHR peptide will allow binding with the pocket in the gp41 NHR that may increase the peptide's antiviral efficacy and its genetic barrier to resistance.
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Affiliation(s)
- Shan Su
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Zhenxuan Ma
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Chen Hua
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Weihua Li
- Key Laboratory of Reproduction Regulation of National Population and Family Planning Commission, The Shanghai Institute of Planned Parenthood Research, Institute of Reproduction and Development, Fudan University, Shanghai 200032, China.
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of MOE/MOH, School of Basic Medical Sciences & Shanghai Public Health Clinical Center, Fudan University, 130 Dong An Rd., Xuhui District, Shanghai 200032, China.
- Key Laboratory of Reproduction Regulation of National Population and Family Planning Commission, The Shanghai Institute of Planned Parenthood Research, Institute of Reproduction and Development, Fudan University, Shanghai 200032, China.
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
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24
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Qi Q, Wang Q, Chen W, Du L, Dimitrov DS, Lu L, Jiang S. HIV-1 gp41-targeting fusion inhibitory peptides enhance the gp120-targeting protein-mediated inactivation of HIV-1 virions. Emerg Microbes Infect 2017. [PMID: 28634358 PMCID: PMC5520319 DOI: 10.1038/emi.2017.46] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Protein- or peptide-based viral inactivators are being developed as novel antiviral drugs with improved efficacy, pharmacokinetics and toxicity profiles because they actively inactivate cell-free human immunodeficiency virus type 1 (HIV-1) virions before attachment to host cells. By contrast, most clinically used antiviral drugs must penetrate host cells to inhibit viral replication. In this study, we pre-treated HIV-1 particles with a gp120-targeting bispecific multivalent protein, 2Dm2m or 4Dm2m, in the presence or absence of the gp41-targeting HIV-1 fusion inhibitory peptides enfuvirtide (T20), T2635, or sifuvirtide (SFT). HIV-1 virions were separated from the inhibitors using PEG-6000, followed by testing of the residual infectivity of the HIV-1 virions. 2Dm2m and 4Dm2m exhibited significant inactivation activity against all HIV-1 strains tested with EC50 values at the low nanomolar level, whereas none of the gp41-targeting peptides showed inactivation activity at concentrations up to 250 nM. Notably, these three peptides significantly enhanced protein-mediated inactivation against cell-free HIV-1 virions, including HIV-1 laboratory-adapted and primary HIV-1 strains, as well as those resistant to T20 or T2635 and virions released from reactivated latently HIV-1-infected cells. These results indicate that the gp120-targeting bispecific multivalent proteins 2Dm2m and 4Dm2m have potential for further development as HIV-1 inactivator-based antiviral drugs for use in the clinic, either alone or in combination with a gp41-targeting HIV-1 fusion inhibitor such as T20, to treat patients with HIV-1 infection and AIDS.
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Affiliation(s)
- Qianqian Qi
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College and Shanghai Public Health Clinical Center, Fudan University, Shanghai 200032, China.,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Qian Wang
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College and Shanghai Public Health Clinical Center, Fudan University, Shanghai 200032, China
| | - Weizao Chen
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Lanying Du
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Dimiter S Dimitrov
- Protein Interactions Section, Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College and Shanghai Public Health Clinical Center, Fudan University, Shanghai 200032, China
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College and Shanghai Public Health Clinical Center, Fudan University, Shanghai 200032, China.,Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
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25
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A novel HIV-1 gp41 tripartite model for rational design of HIV-1 fusion inhibitors with improved antiviral activity. AIDS 2017; 31:885-894. [PMID: 28121713 DOI: 10.1097/qad.0000000000001415] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES During HIV-1 fusion process, the N-terminal heptad repeat (NHR) of the HIV-1 glycoprotein 41 (gp41) interacts with the C-terminal heptad repeat (CHR) to form the fusion active six-helix bundle, thus being an effective target for the design of CHR peptide-based HIV-1 fusion inhibitors. To overcome the limitations of the simplified helix wheel model of six-helix bundle, we herein developed a novel HIV-1 gp41 NHR-CHR-NHR tripartite model for the rational design of HIV-1 fusion inhibitors with improved antiviral activities. DESIGN Based on the crystal structure of six-helix bundle, we evaluated the NHR-binding properties of each residue in CHR. In this new tripartite model, CHR residues were divided into three groups: major binding, nonbinding, and assistant binding sites. METHODS Eight CHR peptides were designed and synthesized to confirm the validity of the tripartite model. Their affinities to NHR and inhibitory activities were analyzed. RESULTS In this tripartite model, replacements in assistant binding sites either increased or decreased the inhibition of HIV-1 infection. We identified three peptides with mutations of the residues in CHR at the assistant binding sites in our tripartite model but nonbinding sites in the helical wheel model. These mutant peptides had anti-HIV-1 activity up to 26-fold more potent than that of C34, a CHR peptide designed on the basis of the helix wheel model. CONCLUSION These data verified the superiority and validity of our new tripartite model for the rational design of HIV-1 fusion inhibitors. This approach can be adapted for designing viral fusion inhibitors against other enveloped viruses with class I membrane fusion protein.
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26
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Creating an Artificial Tail Anchor as a Novel Strategy To Enhance the Potency of Peptide-Based HIV Fusion Inhibitors. J Virol 2016; 91:JVI.01445-16. [PMID: 27795416 DOI: 10.1128/jvi.01445-16] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Accepted: 10/05/2016] [Indexed: 11/20/2022] Open
Abstract
20 (enfuvirtide) and other peptides derived from the human immunodeficiency virus type 1 (HIV-1) gp41 C-terminal heptad repeat (CHR) region inhibit HIV fusion by binding to the hydrophobic grooves on the N-terminal heptad repeat (NHR) trimer and blocking six-helix-bundle (6-HB) formation. Several strategies focusing on the binding grooves of the NHR trimer have been adopted to increase the antiviral activity of the CHR peptides. Here, we developed a novel and simple strategy to greatly enhance the potency of the existing peptide-based HIV fusion inhibitors. First, we identified a shallow pocket adjacent to the groove in the N-terminal region of NHR trimer as a new drug target, and then we designed several short artificial peptides to fit this target. After the addition of IDL (Ile-Asp-Leu) to the C terminus of CHR peptide WQ or MT-WQ, the conjugated peptides, WQ-IDL and MT-WQ-IDL, showed much more potent activities than WQ and T20, respectively, in inhibiting HIV-1 IIIB infection. WQ-IDL and MT-WQ-IDL were also more effective than WQ in blocking HIV-1 Env-mediated membrane fusion and had higher levels of binding affinity with NHR peptide N46. We solved the crystal structure of the 6-HB formed by MT-WQ-IDL and N46 and found that, besides the N-terminal MT hook tail, the IDL tail anchor of MT-WQ-IDL also binds with the shallow hydrophobic pocket outside the groove of the NHR trimer, resulting in enhanced inhibition of HIV-1 fusion with the target cell. It is expected that this novel approach can be widely used to improve the potency of peptidic fusion inhibitors against other enveloped viruses with class I fusion proteins. IMPORTANCE The hydrophobic groove of the human immunodeficiency virus type 1 (HIV-1) gp41 NHR trimer has been known as the classic drug target to develop fusion inhibitors derived from the gp41 CHR. Here, we developed a novel and simple strategy to improve the existing peptide-based HIV fusion inhibitors. We identified a shallow pocket adjacent to the groove in the NHR trimer and added a short artificial peptide consisting of three amino acids (IDL) to the C terminus of a fusion inhibitor to fit this new target. The inhibition activity of this new conjugated peptide was significantly enhanced, by 77-fold, making it much more potent than T20 (enfuvirtide) and suggesting that the IDL tail can be adopted for optimizing existing HIV-1 CHR peptide fusion inhibitors. This new approach of identifying a potential binding pocket outside the traditional target and creating an artificial tail anchor can be widely applied to design novel fusion inhibitors against other class I enveloped viruses, such as Middle East respiratory syndrome coronavirus (MERS-CoV).
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27
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HIV-1 Escape from a Peptidic Anchor Inhibitor through Stabilization of the Envelope Glycoprotein Spike. J Virol 2016; 90:10587-10599. [PMID: 27654295 DOI: 10.1128/jvi.01616-16] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 08/31/2016] [Indexed: 12/17/2022] Open
Abstract
The trimeric HIV-1 envelope glycoprotein spike (Env) mediates viral entry into cells by using a spring-loaded mechanism that allows for the controlled insertion of the Env fusion peptide into the target membrane, followed by membrane fusion. Env is the focus of vaccine research aimed at inducing protective immunity by antibodies as well as efforts to develop drugs that inhibit the viral entry process. The molecular factors contributing to Env stability and decay need to be understood better in order to optimally design vaccines and therapeutics. We generated viruses with resistance to VIR165, a peptidic inhibitor that binds the fusion peptide of the gp41 subunit and prevents its insertion into the target membrane. Interestingly, a number of escape viruses acquired substitutions in the C1 domain of the gp120 subunit (A60E, E64K, and H66R) that rendered these viruses dependent on the inhibitor. These viruses could infect target cells only when VIR165 was present after CD4 binding. Furthermore, the VIR165-dependent viruses were resistant to soluble CD4-induced Env destabilization and decay. These data suggest that VIR165-dependent Env proteins are kinetically trapped in the unliganded state and require the drug to negotiate CD4-induced conformational changes. These studies provide mechanistic insight into the action of the gp41 fusion peptide and its inhibitors and provide new ways to stabilize Env trimer vaccines. IMPORTANCE Because of the rapid development of HIV-1 drug resistance, new drug targets need to be explored continuously. The fusion peptide of the envelope glycoprotein can be targeted by anchor inhibitors. Here we describe virus escape from the anchor inhibitor VIR165. Interestingly, some escape viruses became dependent on the inhibitor for cell entry. We show that the identified escape mutations stabilize the ground state of the envelope glycoprotein and should thus be useful in the design of stabilized envelope-based HIV vaccines.
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28
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Tan J, Yuan H, Li C, Zhang X, Wang C. Insights into the Functions of M-T Hook Structure in HIV Fusion Inhibitor Using Molecular Modeling. Comput Biol Chem 2016; 61:202-9. [DOI: 10.1016/j.compbiolchem.2016.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 01/15/2016] [Accepted: 01/21/2016] [Indexed: 01/13/2023]
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29
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Duan L, Du J, Wang X, Zhou J, Wang X, Liu X. Structural and functional characterization of EIAV gp45 fusion peptide proximal region and asparagine-rich layer. Virology 2016; 491:64-72. [PMID: 26874586 DOI: 10.1016/j.virol.2016.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2015] [Revised: 01/14/2016] [Accepted: 01/19/2016] [Indexed: 10/22/2022]
Abstract
Equine infectious anaemia virus (EIAV) and human immunodeficiency virus (HIV) are members of the lentiviral genus. Similar to HIV gp41, EIAV gp45 is a fusogenic protein that mediates fusion between the viral particle and the host cell membrane. The crystal structure of gp45 reported reveals a different conformation in the here that includes the fusion peptide proximal region (FPPR) and neighboring asparagine-rich layer compared with previous HIV-1 gp41 structures. A complicated hydrogen-bond network containing a cluster of solvent molecules appears to be critical for the stability of the gp45 helical bundle. Interestingly, viral replication was relatively unaffected by site-directed mutagenesis of EIAV, in striking contrast to that of HIV-1. Based on these observations, we speculate that EIAV is more adaptable to emergent mutations, which might be important for the evolution of EIAV as a quasi-species, and could potentially contribute to the success of the EIAV vaccine.
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Affiliation(s)
- Liangwei Duan
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Jiansen Du
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China
| | - Xuefeng Wang
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
| | - Jianhua Zhou
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
| | - Xiaojun Wang
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150001, China
| | - Xinqi Liu
- State Key Laboratory of Medicinal Chemical Biology, College of Life Sciences, Nankai University, Tianjin 300071, China.
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30
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Lu L, Yu F, Cai L, Debnath AK, Jiang S. Development of Small-molecule HIV Entry Inhibitors Specifically Targeting gp120 or gp41. Curr Top Med Chem 2016; 16:1074-90. [PMID: 26324044 PMCID: PMC4775441 DOI: 10.2174/1568026615666150901114527] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 05/17/2015] [Accepted: 05/27/2015] [Indexed: 12/31/2022]
Abstract
Human immunodeficiency virus type 1 (HIV-1) envelope (Env) glycoprotein surface subunit gp120 and transmembrane subunit gp41 play important roles in HIV-1 entry, thus serving as key targets for the development of HIV-1 entry inhibitors. T20 peptide (enfuvirtide) is the first U.S. FDA-approved HIV entry inhibitor; however, its clinical application is limited by the lack of oral availability. Here, we have described the structure and function of the HIV-1 gp120 and gp41 subunits and reviewed advancements in the development of small-molecule HIV entry inhibitors specifically targeting these two Env glycoproteins. We then compared the advantages and disadvantages of different categories of HIV entry inhibitor candidates and further predicted the future trend of HIV entry inhibitor development.
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Affiliation(s)
| | | | | | | | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of MOE/MOH, Shanghai Medical College, Fudan University, 130 Dong An Road, Building #13, Shanghai 200032, China.
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31
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Genetic Pathway of HIV-1 Resistance to Novel Fusion Inhibitors Targeting the Gp41 Pocket. J Virol 2015; 89:12467-79. [PMID: 26446597 DOI: 10.1128/jvi.01741-15] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 09/25/2015] [Indexed: 01/11/2023] Open
Abstract
UNLABELLED The peptide drug enfuvirtide (T20) is the only HIV-1 fusion inhibitor in clinical use, but it easily induces drug resistance, calling for new strategies for developing effective drugs. On the basis of the M-T hook structure, we recently developed highly potent short-peptide HIV-1 fusion inhibitors (MTSC22 and HP23), which mainly target the conserved gp41 pocket and possess high genetic barriers to resistance. Here, we focused on the selection and characterization of HIV-1 escape mutants of MTSC22, which revealed new resistance pathways and mechanisms. Two mutations (E49K and L57R) located at the inhibitor-binding site and two mutations (N126K and E136G) located at the C-terminal heptad repeat region of gp41 were identified as conferring high resistance either singly or in combination. While E49K reduced the C-terminal binding of inhibitors via an electrostatic repulsion, L57R dramatically disrupted the N-terminal binding of M-T hook structure and pocket-binding domain. Unlike E49K and N126K, which enhanced the stability of the endogenous viral six-helical bundle core (6-HB), L57R and E136G conversely destabilized the 6-HB structure. We also demonstrated that both primary and secondary mutations caused the structural changes in 6-HB and severely impaired the capability for HIV-1 entry. Collectively, our data provide novel insights into the mechanisms of short-peptide fusion inhibitors targeting the gp41 pocket site and help increase our understanding of the structure and function of gp41 and HIV-1 evolution. IMPORTANCE The deep pocket on the N-trimer of HIV-1 gp41 has been considered an ideal drug target because of its high degree of conservation and essential role in viral entry. Short-peptide fusion inhibitors, which contain an M-T hook structure and mainly target the pocket site, show extremely high binding and inhibitory activities as well as high genetic barriers to resistance. In this study, the HIV-1 mutants resistant to MTSC22 were selected and characterized, which revealed that the E49K and L57R substitutions at the inhibitor-binding site and the N126K and E136G substitutions at the C-terminal heptad repeat region of gp41 critically determine the resistance phenotype. The data provide novel insights into the mechanisms of action of the M-T hook structure-based fusion inhibitors which will help further our understanding of the structure-function relationship of gp41 and molecular pathways of HIV-1 evolution and eventually facilitate the development of new anti-HIV drugs.
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32
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Chong H, Qiu Z, Su Y, He Y. The N-Terminal T-T Motif of a Third-Generation HIV-1 Fusion Inhibitor Is Not Required for Binding Affinity and Antiviral Activity. J Med Chem 2015; 58:6378-88. [PMID: 26256053 DOI: 10.1021/acs.jmedchem.5b00109] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The highlighted next-generation HIV-1 fusion inhibitor peptide 1 is capped by two threonines. Here, we generated peptide 2 by deleting the T-T motif and compared their structural and antiviral properties. Significantly, two peptides showed similar helical and oligomeric states in solution, comparable binding affinities to the target, and no significant difference to inhibit HIV-1 fusion and infection. Also, the T-T motif was not associated with peptide 1 resistant mutations and its deletion did not affect peptide 1 against enfuvirtide-resistant HIV-1 mutants. The redundancy of the T-T motif was further verified by the model peptide C34 and short peptide inhibitors that mainly target the gp41 pocket, suggesting that the N-terminal T-T motif of peptide 1 could be removed or modified toward the development of new anti-HIV-1 drugs. Consistently, our data have verified that the M-T hook structure rather than the T-T motif is an efficient strategy for short peptide fusion inhibitors.
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Affiliation(s)
- Huihui Chong
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research Center, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College , No. 9, Dong Dan San Tiao, Beijing 100730, China
| | - Zonglin Qiu
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research Center, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College , No. 9, Dong Dan San Tiao, Beijing 100730, China
| | - Yang Su
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research Center, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College , No. 9, Dong Dan San Tiao, Beijing 100730, China
| | - Yuxian He
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research Center, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College , No. 9, Dong Dan San Tiao, Beijing 100730, China
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33
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Zhu X, Yu F, Liu K, Lu L, Jiang S. An artificial peptide-based HIV-1 fusion inhibitor containing M-T hook structure exhibiting improved antiviral potency and drug resistance profile. Future Virol 2015. [DOI: 10.2217/fvl.15.56] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
SUMMARY Aim: We previously designed an artificial HIV-1 fusion inhibitor, PBDtrp-m4HR. Here, we have added two amino acid residues that can form an M-T hook structure at its N-terminus, with the aim of improving its antiviral potency and drug-resistance profile. Methods: Peptides were synthesized and tested for their inhibitory activity on HIV-1 Env-mediated cell–cell fusion and infection by HIV-1 strains, including those resistant to T2635, the third generation HIV fusion inhibitor, as well as its binding affinity to the gp41 NHR-peptide N36. Results: MT-PBDtrp-m4HR exhibited improved inhibitory activity on HIV-1 infection and Env-mediated cell–cell fusion, displayed an improved drug-resistance profile and increased NHR-binding affinity. Conclusion: The added M-T hook is able to enhance or stabilize the interaction between MT-PBDtrp-m4HR and the viral gp41 NHR domain. Therefore, MT-PBDtrp-m4HR has potential to be further developed as a new HIV fusion inhibitor. The approach described in this study can also be used for designing artificial peptides against other enveloped viruses with class I membrane fusion proteins.
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Affiliation(s)
- Xiaojie Zhu
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Fei Yu
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Keliang Liu
- Beijing Institute of Pharmacology & Toxicology, Beijing, China
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
| | - Shibo Jiang
- Key Laboratory of Medical Molecular Virology of Ministries of Education & Health, Shanghai Medical College & Shanghai Public Health Clinical Center, Fudan University, Shanghai, China
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Gordts SC, Férir G, D’huys T, Petrova MI, Lebeer S, Snoeck R, Andrei G, Schols D. The Low-Cost Compound Lignosulfonic Acid (LA) Exhibits Broad-Spectrum Anti-HIV and Anti-HSV Activity and Has Potential for Microbicidal Applications. PLoS One 2015; 10:e0131219. [PMID: 26132818 PMCID: PMC4488490 DOI: 10.1371/journal.pone.0131219] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Accepted: 05/30/2015] [Indexed: 12/24/2022] Open
Abstract
Objectives Lignosulfonic acid (LA), a low-cost lignin-derived polyanionic macromolecule, was extensively studied for its anti-HIV and anti-HSV activity in various cellular assays, its mechanism of viral inhibition and safety profile as potential microbicide. Results LA demonstrated potent inhibitory activity of HIV replication against a wide range of R5 and X4 HIV strains and prevented the uptake of HIV by bystander CD4+ T cells from persistently infected T cells in vitro (IC50: 0.07 – 0.34 μM). LA also inhibited HSV-2 replication in vitro in different cell types (IC50: 0.42 – 1.1 μM) and in rodents in vivo. Furthermore, LA neutralized the HIV-1 and HSV-2 DC-SIGN-mediated viral transfer to CD4+ T cells (IC50: ∼1 μM). In addition, dual HIV-1/HSV-2 infection in T cells was potently blocked by LA (IC50: 0.71 μM). No antiviral activity was observed against the non-enveloped viruses Coxsackie type B4 and Reovirus type 1. LA is defined as a HIV entry inhibitor since it interfered with gp120 binding to the cell surface of T cells. Pretreatment of PBMCs with LA neither increased expression levels of cellular activation markers (CD69, CD25 and HLA-DR), nor enhanced HIV-1 replication. Furthermore, we found that LA had non-antagonistic effects with acyclovir, PRO2000 or LabyA1 (combination index (CI): 0.46 – 1.03) in its anti-HSV-2 activity and synergized with tenofovir (CI: 0.59) in its anti-HIV-1 activity. To identify mechanisms of LA resistance, we generated in vitro a mutant HIV-1 NL4.3LAresistant virus, which acquired seven mutations in the HIV-1 envelope glycoproteins: S160N, V170N, Q280H and R389T in gp120 and K77Q, N113D and H132Y in gp41. Additionally, HIV-1 NL4.3LAresistant virus showed cross-resistance with feglymycin, enfuvirtide, PRO2000 and mAb b12, four well-described HIV binding/fusion inhibitors. Importantly, LA did not affect the growth of vaginal Lactobacilli strains. Conclusion Overall, these data highlight LA as a potential and unique low-cost microbicide displaying broad anti-HIV and anti-HSV activity.
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Affiliation(s)
| | - Geoffrey Férir
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
- * E-mail:
| | - Thomas D’huys
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Mariya I. Petrova
- Centre of Microbial and Plant Genetics, University of Leuven, Leuven, Belgium
- Department of Bioscience Engineering, Antwerp University, Antwerp, Belgium
| | - Sarah Lebeer
- Centre of Microbial and Plant Genetics, University of Leuven, Leuven, Belgium
- Department of Bioscience Engineering, Antwerp University, Antwerp, Belgium
| | - Robert Snoeck
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Graciela Andrei
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
| | - Dominique Schols
- Rega Institute for Medical Research, University of Leuven, Leuven, Belgium
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Mechanism of HIV-1 Resistance to Short-Peptide Fusion Inhibitors Targeting the Gp41 Pocket. J Virol 2015; 89:5801-11. [PMID: 25787278 DOI: 10.1128/jvi.00373-15] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 03/02/2015] [Indexed: 12/29/2022] Open
Abstract
UNLABELLED The deep hydrophobic pocket on the N trimer of HIV-1 gp41 has been considered an ideal drug target. On the basis of the M-T hook structure, we recently developed short-peptide-based HIV-1 fusion inhibitors (MTSC22 and HP23), which mainly target the pocket site and possess highly potent antiviral activity. In this study, we focused on investigating their resistance pathways and mechanisms by escape HIV-1 mutants to SC22EK, a template peptide for MTSC22 and HP23. Two substitutions, E49K and N126K, located, respectively, at the N- and C-heptad repeat regions of gp41, were identified as conferring high resistance to the inhibitors targeting the pocket and cross-resistance to enfuvirtide (T20) and sifuvirtide (SFT). The underlying mechanisms of SC22EK-induced resistance include the following: (i) significantly reduced binding affinity of the inhibitors, (ii) dramatically enhanced interaction of the viral six-helix bundle, and (iii)severely damaged functionality of the viral Env complex. Our data have provided important information for the structure-function relationship of gp41 and the structure-activity relationship of viral fusion inhibitors. IMPORTANCE Enfuvirtide (T20) is the only HIV-1 fusion inhibitor in clinical use, but the problem of resistance significantly limits its use, calling for new strategies or concepts to develop next-generation drugs. On the basis of the M-T hook structure, short-peptide HIV-1 fusion inhibitors specifically targeting the gp41 pocket site exhibit high binding and antiviral activities. Here, we investigated the molecular pathway of HIV-1 resistance to the short inhibitors by selecting and mapping the escape mutants. The key substitutions for resistance and the underlying mechanisms have been finely characterized. The data provide important information for the structure-function relationship of gp41 and its inhibitors and will definitely help our future development of novel drugs that block gp41-dependent fusion.
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The impact of HIV-1 genetic diversity on the efficacy of a combinatorial RNAi-based gene therapy. Gene Ther 2015; 22:485-95. [PMID: 25716532 DOI: 10.1038/gt.2015.11] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Revised: 12/13/2014] [Accepted: 01/15/2015] [Indexed: 11/08/2022]
Abstract
A hurdle for human immunodeficiency virus (HIV-1) therapy is the genomic diversity of circulating viruses and the possibility that drug-resistant virus variants are selected. Although RNA interference (RNAi) is a powerful tool to stably inhibit HIV-1 replication by the expression of antiviral short hairpin RNAs (shRNAs) in transduced T cells, this approach is also vulnerable to pre-existing genetic variation and the development of viral resistance through mutation. To prevent viral escape, we proposed to combine multiple shRNAs against important regions of the HIV-1 RNA genome, which should ideally be conserved in all HIV-1 subtypes. The vulnerability of RNAi therapy to viral escape has been studied for a single subtype B strain, but it is unclear whether the antiviral shRNAs can inhibit diverse virus isolates and subtypes, including drug-resistant variants that could be present in treated patients. To determine the breadth of the RNAi gene therapy approach, we studied the susceptibility of HIV-1 subtypes A-E and drug-resistant variants. In addition, we monitored the evolution of HIV-1 escape variants. We demonstrate that the combinatorial RNAi therapy is highly effective against most isolates, supporting the future testing of this gene therapy in appropriate in vivo models.
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Abstract
ABSTRACT HIV resistance against currently approved entry inhibitors, the chemokine receptor-5 (CCR5) antagonist maraviroc and the fusion inhibitor enfuvirtide (T-20), manifests in a complex manner that is distinct from the resistance patterns against other classes of antiretroviral drugs. Several attachment and fusion inhibitors are currently under various stages of development. Whereas CCR5 co-receptor antagonists have been widely studied until now, because patients who lack CCR5 are healthy and protected to some extent from HIV-infection, CXCR4-antagonist development has been slower, due to limited antiviral activity and potential toxicity given that CXCR4 may have essential cellular functions. Novel fusion inhibitor development is focusing on orally available small-molecule inhibitors that might replace T-20, which needs to be administered by subcutaneous injection.
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Affiliation(s)
- Victor G Kramer
- McGill AIDS Centre, Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada
- Department of Experimental Medicine, McGill University, Montreal, QC, Canada
| | - Mark A Wainberg
- McGill AIDS Centre, Lady Davis Institute, Jewish General Hospital, Montreal, QC, Canada
- Department of Experimental Medicine, McGill University, Montreal, QC, Canada
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Egerer L, Kiem HP, von Laer D. C peptides as entry inhibitors for gene therapy. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 848:191-209. [PMID: 25757622 DOI: 10.1007/978-1-4939-2432-5_10] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Peptides derived from the C-terminal heptad repeat 2 region of the HIV-1 gp41 envelope glycoprotein, so-called C peptides, are very potent HIV-1 fusion inhibitors. Antiviral genes encoding either membrane-anchored (ma) or secreted (iSAVE) C peptides have been engineered and allow direct in vivo production of the therapeutic peptides by genetically modified host cells. Membrane-anchored C peptides expressed in the HIV-1 target cells by T-cell or hematopoietic stem cell gene therapy efficiently prevent virus entry into the modified cells. Such gene-protection confers a selective survival advantage and allows accumulation of the genetically modified cells. Membrane-anchored C peptides have been successfully tested in a nonhuman primate model of AIDS and were found to be safe in a phase I clinical trial in AIDS patients transplanted with autologous gene-modified T-cells. Secreted C peptides have the crucial advantage of not only protecting genetically modified cells from HIV-1 infection, but also neighboring cells, thus suppressing virus replication even if only a small fraction of cells is genetically modified. Accordingly, various cell types can be considered as potential in vivo producer cells for iSAVE-based gene therapeutics, which could even be modified by direct in vivo gene delivery in future. In conclusion, C peptide gene therapeutics may provide a strong benefit to AIDS patients and could present an effective alternative to current antiretroviral drug regimens.
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Affiliation(s)
- Lisa Egerer
- Division of Virology, Department of Hygiene, Microbiology and Social Medicine, Medical University of Innsbruck, Peter Mayr-Str. 4b, Innsbruck, 6020, Austria,
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De Feo CJ, Wang W, Hsieh ML, Zhuang M, Vassell R, Weiss CD. Resistance to N-peptide fusion inhibitors correlates with thermodynamic stability of the gp41 six-helix bundle but not HIV entry kinetics. Retrovirology 2014; 11:86. [PMID: 25274545 PMCID: PMC4190581 DOI: 10.1186/s12977-014-0086-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 09/12/2014] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND The HIV-1 envelope glycoprotein (Env) undergoes conformational changes that mediate fusion between virus and host cell membranes. These changes involve transient exposure of two heptad-repeat domains (HR1 and HR2) in the gp41 subunit and their subsequent self-assembly into a six-helix bundle (6HB) that drives fusion. Env residues and features that influence conformational changes and the rate of virus entry, however, are poorly understood. Peptides corresponding to HR1 and HR2 (N and C peptides, respectively) interrupt formation of the 6HB by binding to the heptad repeats of a fusion-intermediate conformation of Env, making the peptides valuable probes for studying Env conformational changes. RESULTS Using a panel of Envs that are resistant to N-peptide fusion inhibitors, we investigated relationships between virus entry kinetics, 6HB stability, and resistance to peptide fusion inhibitors to elucidate how HR1 and HR2 mutations affect Env conformational changes and virus entry. We found that gp41 resistance mutations increased 6HB stability without increasing entry kinetics. Similarly, we show that increased 6HB thermodynamic stability does not correlate with increased entry kinetics. Thus, N-peptide fusion inhibitors do not necessarily select for Envs with faster entry kinetics, nor does faster entry kinetics predict decreased potency of peptide fusion inhibitors. CONCLUSIONS These findings provide new insights into the relationship between 6HB stability and viral entry kinetics and mechanisms of resistance to inhibitors targeting fusion-intermediate conformations of Env. These studies further highlight how residues in HR1 and HR2 can influence virus entry by altering stability of the 6HB and possibly other conformations of Env that affect rate-limiting steps in HIV entry.
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Affiliation(s)
- Christopher J De Feo
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, 20993, USA.
| | - Wei Wang
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, 20993, USA.
| | - Meng-Lun Hsieh
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, 20993, USA. .,Present address: Michigan State University, Department of Biochemistry and Molecular Biology, Lansing, MI, 48824, USA.
| | - Min Zhuang
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, 20993, USA. .,Present address: Department of Microbiology, Harbin Medical University, Harbin, Heilongjiang, China.
| | - Russell Vassell
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, 20993, USA.
| | - Carol D Weiss
- Center for Biologics Evaluation and Research, US Food and Drug Administration, Silver Spring, MD, 20993, USA.
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Chong H, Yao X, Qiu Z, Sun J, Qiao Y, Zhang M, Wang M, Cui S, He Y. The M-T hook structure increases the potency of HIV-1 fusion inhibitor sifuvirtide and overcomes drug resistance. J Antimicrob Chemother 2014; 69:2759-2769. [DOI: 10.1093/jac/dku183] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023] Open
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Increased replicative fitness can lead to decreased drug sensitivity of hepatitis C virus. J Virol 2014; 88:12098-111. [PMID: 25122776 DOI: 10.1128/jvi.01860-14] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Passage of hepatitis C virus (HCV) in human hepatoma cells resulted in populations that displayed partial resistance to alpha interferon (IFN-α), telaprevir, daclatasvir, cyclosporine, and ribavirin, despite no prior exposure to these drugs. Mutant spectrum analyses and kinetics of virus production in the absence and presence of drugs indicate that resistance is not due to the presence of drug resistance mutations in the mutant spectrum of the initial or passaged populations but to increased replicative fitness acquired during passage. Fitness increases did not alter host factors that lead to shutoff of general host cell protein synthesis and preferential translation of HCV RNA. The results imply that viral replicative fitness is a mechanism of multidrug resistance in HCV. Importance: Viral drug resistance is usually attributed to the presence of amino acid substitutions in the protein targeted by the drug. In the present study with HCV, we show that high viral replicative fitness can confer a general drug resistance phenotype to the virus. The results exclude the possibility that genomes with drug resistance mutations are responsible for the observed phenotype. The fact that replicative fitness can be a determinant of multidrug resistance may explain why the virus is less sensitive to drug treatments in prolonged chronic HCV infections that favor increases in replicative fitness.
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Chong H, Qiu Z, Sun J, Qiao Y, Li X, He Y. Two M-T hook residues greatly improve the antiviral activity and resistance profile of the HIV-1 fusion inhibitor SC29EK. Retrovirology 2014; 11:40. [PMID: 24884671 PMCID: PMC4046051 DOI: 10.1186/1742-4690-11-40] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2014] [Accepted: 04/17/2014] [Indexed: 01/08/2023] Open
Abstract
Background Peptides derived from the C-terminal heptad repeat (CHR) of HIV-1 gp41 such as T20 (Enfuvirtide) and C34 are potent viral fusion inhibitors. We have recently found that two N-terminal residues (Met115 and Thr116) of CHR peptides form a unique M-T hook structure that can greatly enhance the binding and anti-HIV activity of inhibitors. Here, we applied two M-T hook residues to optimize SC29EK, an electrostatically constrained peptide inhibitor with a potent anti-HIV activity. Results The resulting peptide MT-SC29EK showed a dramatically increased binding affinity and could block the six-helical bundle (6-HB) formation more efficiently. As expected, MT-SC29EK potently inhibited HIV-1 entry and infection, especially against those T20- and SC29EK-resistant HIV-1 variants. More importantly, MT-SC29EK and its short form (MT-SC22EK) suffered from the difficulty to induce HIV-1 resistance during the in vitro selection, suggesting their high genetic barriers to the development of resistance. Conclusions Our studies have verified the M-T hook structure as a vital strategy to design novel HIV-1 fusion inhibitors and offered an ideal candidate for clinical development.
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Affiliation(s)
| | | | | | | | | | - Yuxian He
- MOH key Laboratory of Systems Biology of Pathogens and AIDS Research Center, Institute of Pathogen Biology, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, P, R, China.
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Yu F, Lu L, Liu Q, Yu X, Wang L, He E, Zou P, Du L, Sanders RW, Liu S, Jiang S. ADS-J1 inhibits HIV-1 infection and membrane fusion by targeting the highly conserved pocket in the gp41 NHR-trimer. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2014; 1838:1296-305. [PMID: 24388952 DOI: 10.1016/j.bbamem.2013.12.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 12/24/2013] [Accepted: 12/27/2013] [Indexed: 11/16/2022]
Abstract
We previously identified a potent small-molecule human immunodeficiency virus type 1 (HIV-1) fusion inhibitor, termed ADS-J1, and hypothesized that it mainly targeted the hydrophobic pocket in the gp41 N-terminal heptad repeat (NHR) trimer. However, this hypothesis has been challenged by the fact that ADS-J1 cannot induce drug-resistance mutation in the gp41 pocket region. Therefore, we show herein that HIV-1 mutants resistant to T2635, a peptide derived from the gp41 C-terminal heptad repeat (CHR) region with pocket-binding domain (PBD), were also resistant to ADS-J1. We also show that pseudoviruses with mutations at positions 64 and 67 in the gp41 pocket region were highly resistant to ADS-J1 and C34, another CHR-peptide with PBD, but relatively sensitive to T20, a CHR-peptide without PBD. ADS-J1 could effectively bind to N36Fd, a mimic of the gp41 NHR-trimer with pocket exposed, and block binding of C34 to N36Fd trimer to form six-helix bundle (6-HB). However, ADS-J1 was less effective in binding to N36Fd trimer with mutations in the gp41 pocket region, such as N36(Q64A)Fd, N36(Q64L)Fd, N36(A67G)Fd, N36(A67S)Fd, and N36(Q66R)Fd, as well as less effective in blocking 6-HB formation between C34 and these mutant N36Fd trimers. These results confirm that ADS-J1 mainly targets the pocket region in the HIV-1 gp41 NHR trimer and suggest that it could be used as a lead for developing small-molecule HIV fusion inhibitors and as a molecule probe for studying the mechanisms of gp41-mediated membrane fusion.
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Affiliation(s)
- Fei Yu
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China; Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College, Fudan University, Shanghai 200032, China; Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Lu Lu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Qi Liu
- Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College, Fudan University, Shanghai 200032, China
| | - Xiaowen Yu
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Lili Wang
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Elaine He
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Peng Zou
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Lanying Du
- Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA
| | - Rogier W Sanders
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; Weill Medical College of Cornell University, Department of Microbiology and Immunology, New York, NY 10065, USA
| | - Shuwen Liu
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China.
| | - Shibo Jiang
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China; Key Laboratory of Medical Molecular Virology of Ministries of Education and Health, Shanghai Medical College, Fudan University, Shanghai 200032, China; Lindsley F. Kimball Research Institute, New York Blood Center, New York, NY 10065, USA.
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Molecular determinants defining the triggering range of prefusion F complexes of canine distemper virus. J Virol 2013; 88:2951-66. [PMID: 24371057 DOI: 10.1128/jvi.03123-13] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED The morbillivirus cell entry machinery consists of a fusion (F) protein trimer that refolds to mediate membrane fusion following receptor-induced conformational changes in its binding partner, the tetrameric attachment (H) protein. To identify molecular determinants that control F refolding, we generated F chimeras between measles virus (MeV) and canine distemper virus (CDV). We located a central pocket in the globular head domain of CDV F that regulates the stability of the metastable, prefusion conformational state of the F trimer. Most mutations introduced into this "pocket'" appeared to mediate a destabilizing effect, a phenotype associated with enhanced membrane fusion activity. Strikingly, under specific triggering conditions (i.e., variation of receptor type and H protein origin), some F mutants also exhibited resistance to a potent morbillivirus entry inhibitor, which is known to block F triggering by enhancing the stability of prefusion F trimers. Our data reveal that the molecular nature of the F stimulus and the intrinsic stability of metastable prefusion F both regulate the efficiency of F refolding and escape from small-molecule refolding blockers. IMPORTANCE With the aim to better characterize the thermodynamic basis of morbillivirus membrane fusion for cell entry and spread, we report here that the activation energy barrier of prefusion F trimers together with the molecular nature of the triggering "stimulus" (attachment protein and receptor types) define a "triggering range," which governs the initiation of the membrane fusion process. A central "pocket" microdomain in the globular F head contributes substantially to the regulation of the conformational stability of the prefusion complexes. The triggering range also defines the mechanism of viral escape from entry inhibitors and describes how the cellular environment can affect membrane fusion efficiency.
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Abstract
In the absence of a vaccine or a cure, identification of novel HIV-1 inhibitors remains important. A paper in Retrovirology describes a rationally designed bi-specific protein that irreversibly damages the viral envelope glycoprotein complex via a two-punch mechanism. In contrast to traditional drugs that inhibit essential steps in the viral life cycle at the cell surface or in the infected cells, this inhibitor cripples free virus in the absence of cells. See research article: http://www.retrovirology.com/content/9/1/104
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Affiliation(s)
- Rogier W Sanders
- Laboratory of Experimental Virology, Department of Medical Microbiology, Center for Infection and Immunity Amsterdam (CINIMA), Academic Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands.
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HIV-1 resistance mechanism to an electrostatically constrained peptide fusion inhibitor that is active against T-20-resistant strains. Antimicrob Agents Chemother 2013; 57:4035-8. [PMID: 23689710 DOI: 10.1128/aac.00237-13] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
T-20EK is a novel fusion inhibitor designed to have enhanced α-helicity over T-20 (enfuvirtide) through engineered electrostatic interactions between glutamic acid (E) and lysine (K) substitutions. T-20EK efficiently suppresses wild-type and T-20-resistant variants. Here, we selected T-20EK-resistant variants. A combination of L33S and N43K substitutions in gp41 were required for high resistance to T-20EK. While these substitutions also caused resistance to T-20, they did not cause cross-resistance to other known fusion inhibitors.
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Abstract
The human immunodeficiency virus (HIV) enters cells through a series of molecular interactions between the HIV envelope protein and cellular receptors, thus providing many opportunities to block infection. Entry inhibitors are currently being used in the clinic, and many more are under development. Unfortunately, as is the case for other classes of antiretroviral drugs that target later steps in the viral life cycle, HIV can become resistant to entry inhibitors. In contrast to inhibitors that block viral enzymes in intracellular compartments, entry inhibitors interfere with the function of the highly variable envelope glycoprotein as it continuously adapts to changing immune pressure and available target cells in the extracellular environment. Consequently, pathways and mechanisms of resistance for entry inhibitors are varied and often involve mutations across the envelope gene. This review provides a broad overview of entry inhibitor resistance mechanisms that inform our understanding of HIV entry and the design of new inhibitors and vaccines.
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Affiliation(s)
- Christopher J De Feo
- Office of Vaccine Research and Review, Center for Biologics Evaluation and Research, US Food and Drug Administration, 8800 Rockville Pike, Bethesda, MD 20892, USA.
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Menéndez-Arias L. Molecular basis of human immunodeficiency virus type 1 drug resistance: overview and recent developments. Antiviral Res 2013; 98:93-120. [PMID: 23403210 DOI: 10.1016/j.antiviral.2013.01.007] [Citation(s) in RCA: 162] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2013] [Revised: 01/26/2013] [Accepted: 01/29/2013] [Indexed: 12/15/2022]
Abstract
The introduction of potent combination therapies in the mid-90s had a tremendous effect on AIDS mortality. However, drug resistance has been a major factor contributing to antiretroviral therapy failure. Currently, there are 26 drugs approved for treating human immunodeficiency virus (HIV) infections, although some of them are no longer prescribed. Most of the available antiretroviral drugs target HIV genome replication (i.e. reverse transcriptase inhibitors) and viral maturation (i.e. viral protease inhibitors). Other drugs in clinical use include a viral coreceptor antagonist (maraviroc), a fusion inhibitor (enfuvirtide) and two viral integrase inhibitors (raltegravir and elvitegravir). Elvitegravir and the nonnucleoside reverse transcriptase inhibitor rilpivirine have been the most recent additions to the antiretroviral drug armamentarium. An overview of the molecular mechanisms involved in antiretroviral drug resistance and the role of drug resistance-associated mutations was previously presented (Menéndez-Arias, L., 2010. Molecular basis of human immunodeficiency virus drug resistance: an update. Antiviral Res. 85, 210-231). This article provides now an updated review that covers currently approved drugs, new experimental agents (e.g. neutralizing antibodies) and selected drugs in preclinical or early clinical development (e.g. experimental integrase inhibitors). Special attention is dedicated to recent research on resistance to reverse transcriptase and integrase inhibitors. In addition, recently discovered interactions between HIV and host proteins and novel strategies to block HIV assembly or viral entry emerge as promising alternatives for the development of effective antiretroviral treatments.
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Affiliation(s)
- Luis Menéndez-Arias
- Centro de Biología Molecular "Severo Ochoa"-Consejo Superior de Investigaciones Científicas & Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Campus de Cantoblanco, 28049 Madrid, Spain.
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Izumi K, Kawaji K, Miyamoto F, Shimane K, Shimura K, Sakagami Y, Hattori T, Watanabe K, Oishi S, Fujii N, Matsuoka M, Kaku M, Sarafianos SG, Kodama EN. Mechanism of resistance to S138A substituted enfuvirtide and its application to peptide design. Int J Biochem Cell Biol 2013; 45:908-15. [PMID: 23357451 DOI: 10.1016/j.biocel.2013.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 01/15/2013] [Accepted: 01/20/2013] [Indexed: 11/19/2022]
Abstract
T-20 (enfuvirtide) resistance is caused by the N43D primary resistance mutation at its presumed binding site at the N-terminal heptad repeat (N-HR) of gp41, accompanied by the S138A secondary mutation at the C-terminal HR of gp41 (C-HR). We have discovered that modifying T-20 to include S138A (T-20S138A) allows it to efficiently block wild-type and T20-resistant viruses, by a mechanism that involves improved binding of T-20S138A to the N-HR that contains the N43D primary mutation. To determine how HIV-1 in turn escapes T-20S138A we used a dose escalation method to select T-20S138A-resistant HIV-1 starting with either wild-type (HIV-1WT) or T-20-resistant (HIV-1N43D/S138A) virus. We found that when starting with WT background, I37N and L44M emerged in the N-HR of gp41, and N126K in the C-HR. However, when starting with HIV-1N43D/S138A, L33S and I69L emerged in N-HR, and E137K in C-HR. T-20S138A-resistant recombinant HIV-1 showed cross-resistance to other T-20 derivatives, but not to C34 derivatives, suggesting that T-20S138A suppressed HIV-1 replication by a similar mechanism to T-20. Furthermore, E137K enhanced viral replication kinetics and restored binding affinity with N-HR containing N43D, indicating that it acts as a secondary, compensatory mutation. We therefore introduced E137K into T-20S138A (T-20E137K/S138A) and revealed that T-20E137K/S138A moderately suppressed replication of T-20S138A-resistant HIV-1. T-20E137K/S138A retained activity to HIV-1 without L33S, which seems to be a key mutation for T-20 derivatives. Our data demonstrate that secondary mutations can be consistently used for the design of peptide inhibitors that block replication of HIV resistant to fusion inhibitors.
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Affiliation(s)
- Kazuki Izumi
- Laboratory of Virus Control, Institute for Virus Research, Kyoto University, 53 Shogoin Kawaramachi, Kyoto 606-8507, Japan
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Chong H, Yao X, Qiu Z, Sun J, Zhang M, Waltersperger S, Wang M, Liu S, Cui S, He Y. Short‐peptide fusion inhibitors with high potency against wild‐type and enfuvirtide‐resistant HIV‐1. FASEB J 2012; 27:1203-13. [DOI: 10.1096/fj.12-222547] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Huihui Chong
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Xue Yao
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Zonglin Qiu
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Jianping Sun
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Meng Zhang
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | | | - Meitian Wang
- Swiss Light SourcePaul Scherrer InstituteVilligenSwitzerland
| | - Shan‐Lu Liu
- Department of Molecular Microbiology and ImmunologyUniversity of MissouriColumbiaMissouriUSA
| | - Sheng Cui
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
| | - Yuxian He
- MOH Key Laboratory of Systems Biology of Pathogens and AIDS Research CenterInstitute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina
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