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Domingo E, García-Crespo C, Soria ME, Perales C. Viral Fitness, Population Complexity, Host Interactions, and Resistance to Antiviral Agents. Curr Top Microbiol Immunol 2023; 439:197-235. [PMID: 36592247 DOI: 10.1007/978-3-031-15640-3_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fitness of viruses has become a standard parameter to quantify their adaptation to a biological environment. Fitness determinations for RNA viruses (and some highly variable DNA viruses) meet with several uncertainties. Of particular interest are those that arise from mutant spectrum complexity, absence of population equilibrium, and internal interactions among components of a mutant spectrum. Here, concepts, fitness measurements, limitations, and current views on experimental viral fitness landscapes are discussed. The effect of viral fitness on resistance to antiviral agents is covered in some detail since it constitutes a widespread problem in antiviral pharmacology, and a challenge for the design of effective antiviral treatments. Recent evidence with hepatitis C virus suggests the operation of mechanisms of antiviral resistance additional to the standard selection of drug-escape mutants. The possibility that high replicative fitness may be the driver of such alternative mechanisms is considered. New broad-spectrum antiviral designs that target viral fitness may curtail the impact of drug-escape mutants in treatment failures. We consider to what extent fitness-related concepts apply to coronaviruses and how they may affect strategies for COVID-19 prevention and treatment.
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Affiliation(s)
- Esteban Domingo
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain.
| | - Carlos García-Crespo
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - María Eugenia Soria
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040, Madrid, Spain
| | - Celia Perales
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040, Madrid, Spain.,Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain
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2
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Khan SN, Persons JD, Guerrero M, Ilina TV, Oda M, Ishima R. A synergy of activity, stability, and inhibitor-interaction of HIV-1 protease mutants evolved under drug-pressure. Protein Sci 2020; 30:571-582. [PMID: 33314454 DOI: 10.1002/pro.4013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 12/04/2020] [Accepted: 12/06/2020] [Indexed: 01/01/2023]
Abstract
A clinically-relevant, drug-resistant mutant of HIV-1 protease (PR), termed Flap+(I54V) and containing L10I, G48V, I54V and V82A mutations, is known to produce significant changes in the entropy and enthalpy balance of drug-PR interactions, compared to wild-type PR. A similar mutant, Flap+(I54A) , which evolves from Flap+(I54V) and contains the single change at residue 54 relative to Flap+(I54V) , does not. Yet, how Flap+(I54A) behaves in solution is not known. To understand the molecular basis of V54A evolution, we compared nuclear magnetic resonance (NMR) spectroscopy, fluorescence spectroscopy, isothermal titration calorimetry, and enzymatic assay data from four PR proteins: PR (pWT), Flap+(I54V) , Flap+(I54A) , and Flap+(I54) , a control mutant that contains only L10I, G48V and V82A mutations. Our data consistently show that selection to the smaller side chain at residue 54, not only decreases inhibitor affinity, but also restores the catalytic activity.
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Affiliation(s)
- Shahid N Khan
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.,Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - John D Persons
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Michel Guerrero
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Tatiana V Ilina
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Masayuki Oda
- Graduate School of Life and Environmental Sciences, Kyoto Prefectural University, Kyoto, Japan
| | - Rieko Ishima
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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3
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Domingo E, de Ávila AI, Gallego I, Sheldon J, Perales C. Viral fitness: history and relevance for viral pathogenesis and antiviral interventions. Pathog Dis 2020; 77:5454742. [PMID: 30980658 DOI: 10.1093/femspd/ftz021] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/06/2019] [Indexed: 02/06/2023] Open
Abstract
The quasispecies dynamics of viral populations (continuous generation of variant genomes and competition among them) has as one of its frequent consequences variations in overall multiplication capacity, a major component of viral fitness. This parameter has multiple implications for viral pathogenesis and viral disease control, some of them unveiled thanks to deep sequencing of viral populations. Darwinian fitness is an old concept whose quantification dates back to the early developments of population genetics. It was later applied to viruses (mainly to RNA viruses) to quantify relative multiplication capacities of individual mutant clones or complex populations. The present article reviews the fitness concept and its relevance for the understanding of the adaptive dynamics of viruses in constant and changing environments. Many studies have addressed the fitness cost of escape mutations (to antibodies, cytotoxic T cells or inhibitors) as an influence on the efficacy of antiviral interventions. Here, we summarize the evidence that the basal fitness level can be a determinant of inhibitor resistance.
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Affiliation(s)
- Esteban Domingo
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), C/ Nicolás Cabrera 1, Campus de Cantoblanco, Madrid 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) del Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Ana I de Ávila
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), C/ Nicolás Cabrera 1, Campus de Cantoblanco, Madrid 28049, Spain
| | - Isabel Gallego
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), C/ Nicolás Cabrera 1, Campus de Cantoblanco, Madrid 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) del Instituto de Salud Carlos III, Madrid 28029, Spain
| | - Julie Sheldon
- Institute of Experimental Virology, Twincore, Centre for Experimental and Clinical Infection Research, A Joint Venture Between Medical School Hannover (MHH) and Helmholtz Centre for Infection Research (HZI), D-30625, Hannover, Germany
| | - Celia Perales
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), C/ Nicolás Cabrera 1, Campus de Cantoblanco, Madrid 28049, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) del Instituto de Salud Carlos III, Madrid 28029, Spain.,Department of Clinical Microbiology, IIS-Fundación Jiménez Díaz, UAM. Av. Reyes Católicos 2, Madrid 28040, Spain
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Maeda K, Das D, Kobayakawa T, Tamamura H, Takeuchi H. Discovery and Development of Anti-HIV Therapeutic Agents: Progress Towards Improved HIV Medication. Curr Top Med Chem 2019; 19:1621-1649. [PMID: 31424371 PMCID: PMC7132033 DOI: 10.2174/1568026619666190712204603] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/14/2019] [Accepted: 06/21/2019] [Indexed: 01/09/2023]
Abstract
The history of the human immunodeficiency virus (HIV)/AIDS therapy, which spans over 30 years, is one of the most dramatic stories of science and medicine leading to the treatment of a disease. Since the advent of the first AIDS drug, AZT or zidovudine, a number of agents acting on different drug targets, such as HIV enzymes (e.g. reverse transcriptase, protease, and integrase) and host cell factors critical for HIV infection (e.g. CD4 and CCR5), have been added to our armamentarium to combat HIV/AIDS. In this review article, we first discuss the history of the development of anti-HIV drugs, during which several problems such as drug-induced side effects and the emergence of drug-resistant viruses became apparent and had to be overcome. Nowadays, the success of Combination Antiretroviral Therapy (cART), combined with recently-developed powerful but nonetheless less toxic drugs has transformed HIV/AIDS from an inevitably fatal disease into a manageable chronic infection. However, even with such potent cART, it is impossible to eradicate HIV because none of the currently available HIV drugs are effective in eliminating occult “dormant” HIV cell reservoirs. A number of novel unique treatment approaches that should drastically improve the quality of life (QOL) of patients or might actually be able to eliminate HIV altogether have also been discussed later in the review.
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Affiliation(s)
- Kenji Maeda
- National Center for Global Health and Medicine (NCGM) Research Institute, Tokyo 162-8655, Japan
| | - Debananda Das
- Experimental Retrovirology Section, HIV and AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health (NCI/NIH), Bethesda, MD, United States
| | - Takuya Kobayakawa
- Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University (TMDU), Tokyo 101-0062, Japan
| | - Hirokazu Tamamura
- Department of Molecular Virology, Tokyo Medical and Dental University (TMDU), Tokyo 113-8519, Japan
| | - Hiroaki Takeuchi
- Department of Molecular Virology, Tokyo Medical and Dental University (TMDU), Tokyo 113-8519, Japan
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5
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Ishima R, Kurt Yilmaz N, Schiffer CA. NMR and MD studies combined to elucidate inhibitor and water interactions of HIV-1 protease and their modulations with resistance mutations. JOURNAL OF BIOMOLECULAR NMR 2019; 73:365-374. [PMID: 31243634 PMCID: PMC6941145 DOI: 10.1007/s10858-019-00260-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Accepted: 06/19/2019] [Indexed: 06/09/2023]
Abstract
Over the last two decades, both the sensitivity of NMR and the time scale of molecular dynamics (MD) simulation have increased tremendously and have advanced the field of protein dynamics. HIV-1 protease has been extensively studied using these two methods, and has presented a framework for cross-evaluation of structural ensembles and internal dynamics by integrating the two methods. Here, we review studies from our laboratories over the last several years, to understand the mechanistic basis of protease drug-resistance mutations and inhibitor responses, using NMR and crystal structure-based parallel MD simulations. Our studies demonstrate that NMR relaxation experiments, together with crystal structures and MD simulations, significantly contributed to the current understanding of structural/dynamic changes due to HIV-1 protease drug resistance mutations.
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Affiliation(s)
- Rieko Ishima
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Nese Kurt Yilmaz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Celia A Schiffer
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA.
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6
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Khan SN, Persons JD, Paulsen JL, Guerrero M, Schiffer CA, Kurt-Yilmaz N, Ishima R. Probing Structural Changes among Analogous Inhibitor-Bound Forms of HIV-1 Protease and a Drug-Resistant Mutant in Solution by Nuclear Magnetic Resonance. Biochemistry 2018; 57:1652-1662. [PMID: 29457713 PMCID: PMC5850901 DOI: 10.1021/acs.biochem.7b01238] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the era of state-of-the-art inhibitor design and high-resolution structural studies, detection of significant but small protein structural differences in the inhibitor-bound forms is critical to further developing the inhibitor. Here, we probed differences in HIV-1 protease (PR) conformation among darunavir and four analogous inhibitor-bound forms and compared them with a drug-resistant mutant using nuclear magnetic resonance chemical shifts. Changes in amide chemical shifts of wild-type (WT) PR among these inhibitor-bound forms, ΔCSP, were subtle but detectable and extended >10 Å from the inhibitor-binding site, asymmetrically between the two subunits of PR. Molecular dynamics simulations revealed differential local hydrogen bonding as the molecular basis of this remote asymmetric change. Inhibitor-bound forms of the drug-resistant mutant also showed a similar long-range ΔCSP pattern. Differences in ΔCSP values of the WT and the mutant (ΔΔCSPs) were observed at the inhibitor-binding site and in the surrounding region. Comparing chemical shift changes among highly analogous inhibitors and ΔΔCSPs effectively eliminated local environmental effects stemming from different chemical groups and enabled exploitation of these sensitive parameters to detect subtle protein conformational changes and to elucidate asymmetric and remote conformational effects upon inhibitor interaction.
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Affiliation(s)
- Shahid N Khan
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - John D Persons
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Janet L. Paulsen
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Michel Guerrero
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Celia A. Schiffer
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Nese Kurt-Yilmaz
- Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA, USA
| | - Rieko Ishima
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Sutherland KA, Collier DA, Claiborne DT, Prince JL, Deymier MJ, Goldstein RA, Hunter E, Gupta RK. Wide variation in susceptibility of transmitted/founder HIV-1 subtype C Isolates to protease inhibitors and association with in vitro replication efficiency. Sci Rep 2016; 6:38153. [PMID: 27901085 PMCID: PMC5128871 DOI: 10.1038/srep38153] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/04/2016] [Indexed: 02/07/2023] Open
Abstract
The gag gene is highly polymorphic across HIV-1 subtypes and contributes to susceptibility to protease inhibitors (PI), a critical class of antiretrovirals that will be used in up to 2 million individuals as second-line therapy in sub Saharan Africa by 2020. Given subtype C represents around half of all HIV-1 infections globally, we examined PI susceptibility in subtype C viruses from treatment-naïve individuals. PI susceptibility was measured in a single round infection assay of full-length, replication competent MJ4/gag chimeric viruses, encoding the gag gene and 142 nucleotides of pro derived from viruses in 20 patients in the Zambia-Emory HIV Research Project acute infection cohort. Ten-fold variation in susceptibility to PIs atazanavir and lopinavir was observed across 20 viruses, with EC50s ranging 0.71-6.95 nM for atazanvir and 0.64-8.54 nM for lopinavir. Ten amino acid residues in Gag correlated with lopinavir EC50 (p < 0.01), of which 380 K and 389I showed modest impacts on in vitro drug susceptibility. Finally a significant relationship between drug susceptibility and replication capacity was observed for atazanavir and lopinavir but not darunavir. Our findings demonstrate large variation in susceptibility of PI-naïve subtype C viruses that appears to correlate with replication efficiency and could impact clinical outcomes.
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Caljon G, De Muylder G, Durnez L, Jennes W, Vanaerschot M, Dujardin JC. Alice in microbes' land: adaptations and counter-adaptations of vector-borne parasitic protozoa and their hosts. FEMS Microbiol Rev 2016; 40:664-85. [PMID: 27400870 DOI: 10.1093/femsre/fuw018] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/03/2016] [Indexed: 12/24/2022] Open
Abstract
In the present review, we aim to provide a general introduction to different facets of the arms race between pathogens and their hosts/environment, emphasizing its evolutionary aspects. We focus on vector-borne parasitic protozoa, which have to adapt to both invertebrate and vertebrate hosts. Using Leishmania, Trypanosoma and Plasmodium as main models, we review successively (i) the adaptations and counter-adaptations of parasites and their invertebrate host, (ii) the adaptations and counter-adaptations of parasites and their vertebrate host and (iii) the impact of human interventions (chemotherapy, vaccination, vector control and environmental changes) on these adaptations. We conclude by discussing the practical impact this knowledge can have on translational research and public health.
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Affiliation(s)
- Guy Caljon
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium University of Antwerp, Department of Biomedical Sciences, Laboratory of Microbiology, Parasitology and Health, Universiteitsplein 1, B-2610 Wilrijk, Belgium
| | - Géraldine De Muylder
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Lies Durnez
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Wim Jennes
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium
| | - Manu Vanaerschot
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium Columbia University, College of Physicians and Surgeons, Department of Microbiology and Immunology, Fidock Lab, New York, NY 10032, USA
| | - Jean-Claude Dujardin
- Institute of Tropical Medicine, Department of Biomedical Sciences, Nationalestraat 155, B-2000 Antwerp, Belgium University of Antwerp, Department of Biomedical Sciences, Laboratory of Microbiology, Parasitology and Health, Universiteitsplein 1, B-2610 Wilrijk, Belgium
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Consequences of prior use of full-dose ritonavir as single protease inhibitor as part of combination antiretroviral regimens on the future therapy choices in HIV-1-infected children. Pediatr Infect Dis J 2014; 33:e53-9. [PMID: 23958813 DOI: 10.1097/inf.0b013e31829f2694] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND South African HIV-infected infants below age 6 months and children younger than 3 years on concomitant antimycobacterial treatment received full-dose ritonavir single protease inhibitor (RTV-sPI), together with 2 nucleoside reverse transcriptase inhibitors, from 2004 until 2008. Use of RTV-sPI has been described as a risk factor for PI drug resistance, but the extent of this resistance is unknown. AIM This research assesses clinical and virological outcome of a pediatric RTV-sPI cohort at a large South African antiretroviral therapy (ART) site in a high-burden tuberculosis setting, including resistance mutations in those failing ART. METHODS All children initiated at Kalafong hospital before December 2008, who ever received RTV-sPI-based regimens, were assessed for patient outcome, virological failure and drug resistance. HIV viral loads were done 6-monthly and HIV genotyping since 2009. RESULTS There were 178 children who ever received RTV-sPI, with a mean age at ART initiation of 1.4 years. Of the 135 children (76%) with >6 months follow-up, 17 children (13%) never had viral suppression, whereas another 25 (18%) developed virological failure later. Nineteen of 26 children (73%) with genotypic resistance results had major PI mutations. CONCLUSIONS Treatment failure is not a universal feature in children with prior exposure to RTV-sPI regimens, but the significant proportion (31%) with virological failure is of concern due to high prevalence of major PI- and multiclass mutations. These children currently have no treatment options in the South African public sector, highlighting the urgent need for access to alternative ART regimens to ensure improved outcomes.
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10
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Blanco Arévalo JL, Whitlock GG. Dolutegravir: an exciting new kid on the block. Expert Opin Pharmacother 2014; 15:573-82. [DOI: 10.1517/14656566.2014.868883] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
The most significant advance in the medical management of HIV-1 infection has been the treatment of patients with antiviral drugs, which can suppress HIV-1 replication to undetectable levels. The discovery of HIV-1 as the causative agent of AIDS together with an ever-increasing understanding of the virus replication cycle have been instrumental in this effort by providing researchers with the knowledge and tools required to prosecute drug discovery efforts focused on targeted inhibition with specific pharmacological agents. To date, an arsenal of 24 Food and Drug Administration (FDA)-approved drugs are available for treatment of HIV-1 infections. These drugs are distributed into six distinct classes based on their molecular mechanism and resistance profiles: (1) nucleoside-analog reverse transcriptase inhibitors (NNRTIs), (2) non-nucleoside reverse transcriptase inhibitors (NNRTIs), (3) integrase inhibitors, (4) protease inhibitors (PIs), (5) fusion inhibitors, and (6) coreceptor antagonists. In this article, we will review the basic principles of antiretroviral drug therapy, the mode of drug action, and the factors leading to treatment failure (i.e., drug resistance).
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Affiliation(s)
- Eric J Arts
- Ugandan CFAR Laboratories, Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, Ohio 44106, USA.
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12
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Mesplède T, Quashie PK, Osman N, Han Y, Singhroy DN, Lie Y, Petropoulos CJ, Huang W, Wainberg MA. Viral fitness cost prevents HIV-1 from evading dolutegravir drug pressure. Retrovirology 2013; 10:22. [PMID: 23432922 PMCID: PMC3598531 DOI: 10.1186/1742-4690-10-22] [Citation(s) in RCA: 106] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 02/20/2013] [Indexed: 12/14/2022] Open
Abstract
Background Clinical studies have shown that integrase strand transfer inhibitors can be used to treat HIV-1 infection. Although the first-generation integrase inhibitors are susceptible to the emergence of resistance mutations that impair their efficacy in therapy, such resistance has not been identified to date in drug-naïve patients who have been treated with the second-generation inhibitor dolutegravir. During previous in vitro selection study, we identified a R263K mutation as the most common substitution to arise in the presence of dolutegravir with H51Y arising as a secondary mutation. Additional experiments reported here provide a plausible explanation for the absence of reported dolutegravir resistance among integrase inhibitor-naïve patients to date. Results We now show that H51Y in combination with R263K increases resistance to dolutegravir but is accompanied by dramatic decreases in both enzymatic activity and viral replication. Conclusions Since H51Y and R263K may define a unique resistance pathway to dolutegravir, our results are consistent with the absence of resistance mutations in antiretroviral drug-naive patients treated with this drug.
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Affiliation(s)
- Thibault Mesplède
- McGill University AIDS Centre, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Quebec, Canada
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The emergence of HIV-1 primary drug resistance genotypes among treatment-naïve men who have sex with men in high-prevalence areas in China. Arch Virol 2012; 158:839-44. [PMID: 23224760 DOI: 10.1007/s00705-012-1557-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2012] [Accepted: 10/16/2012] [Indexed: 10/27/2022]
Abstract
The prevalence of HIV-1 infection in men who have sex with men (MSM) in China has drastically increased, and circulating strains may have acquired transmitted drug resistance (TDR). We determined TDR genotypes among antiretroviral therapy (ART)-naïve MSM in 19 provinces/cities where HIV-1 prevalence among MSM is high, and found an overall 4.9 % TDR rate. Although protease inhibitors (PI) were not in the first-line antiretroviral drug list provided through the National ART Program, 70.4 % of the detected TDR belongs to this category. Our findings confirm the urgent need for TDR surveillance in order to optimize treatment effects of the National ART Program.
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14
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Uncommon pathways of immune escape attenuate HIV-1 integrase replication capacity. J Virol 2012; 86:6913-23. [PMID: 22496233 DOI: 10.1128/jvi.07133-11] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An attenuation of the HIV-1 replication capacity (RC) has been observed for immune-mediated escape mutations in Gag restricted by protective HLA alleles. However, the extent to which escape mutations affect other viral proteins during natural infection is not well understood. We generated recombinant viruses encoding plasma HIV-1 RNA integrase sequences from antiretroviral-naïve individuals with early (n = 88) and chronic (n = 304) infections and measured the in vitro RC of each. In contrast to data from previous studies of Gag, we observed little evidence that host HLA allele expression was associated with integrase RC. A modest negative correlation was observed between the number of HLA-B-associated integrase polymorphisms and RC in chronic infection (R = -0.2; P = 0.003); however, this effect was not driven by mutations restricted by protective HLA alleles. Notably, the integrase variants S119R, G163E, and I220L, which represent uncommon polymorphisms associated with HLA-C*05, -A*33, and -B*52, respectively, correlated with lower RC (all q < 0.2). We identified a novel C*05-restricted epitope (HTDNGSNF(114-121)) that likely contributes to the selection of the S119R variant, the polymorphism most significantly associated with lower RC in patient sequences. An NL4-3 mutant encoding the S119R polymorphism displayed a ~35%-reduced function that was rescued by a single compensatory mutation of A91E. Together, these data indicate that substantial HLA-driven attenuation of integrase is not a general phenomenon during HIV-1 adaptation to host immunity. However, uncommon polymorphisms selected by HLA alleles that are not conventionally regarded to be protective may be associated with impaired protein function. Vulnerable epitopes in integrase might therefore be considered for future vaccine strategies.
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15
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Distinct effects of two HIV-1 capsid assembly inhibitor families that bind the same site within the N-terminal domain of the viral CA protein. J Virol 2012; 86:6643-55. [PMID: 22496222 DOI: 10.1128/jvi.00493-12] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The emergence of resistance to existing classes of antiretroviral drugs necessitates finding new HIV-1 targets for drug discovery. The viral capsid (CA) protein represents one such potential new target. CA is sufficient to form mature HIV-1 capsids in vitro, and extensive structure-function and mutational analyses of CA have shown that the proper assembly, morphology, and stability of the mature capsid core are essential for the infectivity of HIV-1 virions. Here we describe the development of an in vitro capsid assembly assay based on the association of CA-NC subunits on immobilized oligonucleotides. This assay was used to screen a compound library, yielding several different families of compounds that inhibited capsid assembly. Optimization of two chemical series, termed the benzodiazepines (BD) and the benzimidazoles (BM), resulted in compounds with potent antiviral activity against wild-type and drug-resistant HIV-1. Nuclear magnetic resonance (NMR) spectroscopic and X-ray crystallographic analyses showed that both series of inhibitors bound to the N-terminal domain of CA. These inhibitors induce the formation of a pocket that overlaps with the binding site for the previously reported CAP inhibitors but is expanded significantly by these new, more potent CA inhibitors. Virus release and electron microscopic (EM) studies showed that the BD compounds prevented virion release, whereas the BM compounds inhibited the formation of the mature capsid. Passage of virus in the presence of the inhibitors selected for resistance mutations that mapped to highly conserved residues surrounding the inhibitor binding pocket, but also to the C-terminal domain of CA. The resistance mutations selected by the two series differed, consistent with differences in their interactions within the pocket, and most also impaired virus replicative capacity. Resistance mutations had two modes of action, either directly impacting inhibitor binding affinity or apparently increasing the overall stability of the viral capsid without affecting inhibitor binding. These studies demonstrate that CA is a viable antiviral target and demonstrate that inhibitors that bind within the same site on CA can have distinct binding modes and mechanisms of action.
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Sanjuán R, Lázaro E, Vignuzzi M. Biomedical implications of viral mutation and evolution. Future Virol 2012. [DOI: 10.2217/fvl.12.19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Mutation rates vary hugely across viruses and strongly determine their evolution. In addition, viral mutation and evolution are biomedically relevant because they can determine pathogenesis, vaccine efficacy and antiviral resistance. We review experimental methods for estimating viral mutation rates and how these estimates vary across viral groups, paying special attention to the more general trends. Recent advances positing a direct association between viral mutation rates and virulence, or the use of high-fidelity variants as attenuated vaccines, are also discussed. Finally, we review the implications of viral mutation and evolution for the design of rational antiviral therapies and for efficient epidemiological surveillance.
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Affiliation(s)
- Rafael Sanjuán
- Instituto Cavanilles de Biodiversidad y Biología Evolutiva, Universitat de València, Valencia, Spain
| | - Ester Lázaro
- Centro de Astrobiología, CSIC-INTA, Madrid, Spain
| | - Marco Vignuzzi
- Institut Pasteur, Viral Populations & Pathogenesis Laboratory, Paris, France
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Selhorst P, Vazquez AC, Terrazas-Aranda K, Michiels J, Vereecken K, Heyndrickx L, Weber J, Quiñones-Mateu ME, Ariën KK, Vanham G. Human immunodeficiency virus type 1 resistance or cross-resistance to nonnucleoside reverse transcriptase inhibitors currently under development as microbicides. Antimicrob Agents Chemother 2011; 55:1403-13. [PMID: 21282453 PMCID: PMC3067143 DOI: 10.1128/aac.01426-10] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 11/29/2010] [Accepted: 01/19/2011] [Indexed: 11/20/2022] Open
Abstract
Microbicides based on nonnucleoside reverse transcriptase inhibitors (NNRTIs) are currently being developed to protect women from HIV acquisition through sexual contact. However, the large-scale introduction of these products raises two major concerns. First, when these microbicides are used by undiagnosed HIV-positive women, they could potentially select for viral resistance, which may compromise subsequent therapeutic options. Second, NNRTI-based microbicides that are inactive against NNRTI-resistant strains might promote the selective transmission of these viruses. In order to address these concerns, drug resistance was selected in vitro by the serial passage of three viral isolates from subtypes B and C and CRF02_AG (a circulating recombinant form) in activated peripheral blood mononuclear cells (PBMCs) under conditions of increasing concentrations of three NNRTIs (i.e., TMC120, UC781, and MIV-160) that are currently being developed as candidate microbicides. TMC120 and MIV-160 displayed a high genetic barrier to resistance development, whereas resistance to UC781 emerged rapidly, similarly to efavirenz and nevirapine. Phenotypically, the selected viruses appeared to be highly cross-resistant to current first-line therapeutic NNRTIs (i.e., delavirdine, nevirapine, and efavirenz), although they retained some susceptibility to the more recently developed NNRTIs lersivirine and etravirine. The ability of UC781, TMC120, and MIV-160 to inhibit the in vitro-selected NNRTI-resistant viruses was also limited, although residual activity could be observed for the candidate microbicide NNRTI MIV-170. Interestingly, only four p2/p7/p1/p6/PR/RT/INT recombinant NNRTI-resistant viruses (i.e., TMC120-resistant VI829, EFV-resistant VI829, MIV-160-resistant VI829, and EFV-resistant MP568) showed impairments in replicative fitness. Overall, these in vitro analyses demonstrate that due to potential cross-resistance, the large-scale introduction of single-NNRTI-based microbicides should be considered with caution.
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Affiliation(s)
- Philippe Selhorst
- Department of Microbiology, Virology Unit, Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium.
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Gelman MA, Glenn JS. Mixing the right hepatitis C inhibitor cocktail. Trends Mol Med 2011; 17:34-46. [PMID: 21106440 PMCID: PMC3085044 DOI: 10.1016/j.molmed.2010.10.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 09/23/2010] [Accepted: 10/11/2010] [Indexed: 01/06/2023]
Abstract
Therapy for hepatitis C virus (HCV) infection is on the cusp of a new era. Until now, standard-of-care therapy has involved interferon (IFN) and ribavirin. With the first successful Phase III trials of specific targeted antiviral therapy for HCV (STAT-C) compounds, as well as three trials in progress giving the first glimpse of IFN-free combinations of STAT-C agents, this review looks ahead to the new classes of anti-HCV agents currently in clinical development. Successful pharmacologic control of HIV and TB frames the discussion, as well as consideration of the mutation frequency of HCV replication. Maximizing synergy between agents and minimizing cumulative toxicity will be critical to the design of future IFN-free STAT-C regimens.
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Affiliation(s)
- Michael A. Gelman
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, California
| | - Jeffrey S. Glenn
- Division of Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, California
- Veterans Administration Medical Center, Palo Alto, California
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Applegate TL, Birkett DJ, Mcintyre GJ, Jaramillo AB, Symonds G, Murray JM. In silico modeling indicates the development of HIV-1 resistance to multiple shRNA gene therapy differs to standard antiretroviral therapy. Retrovirology 2010; 7:83. [PMID: 20932334 PMCID: PMC2959037 DOI: 10.1186/1742-4690-7-83] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2010] [Accepted: 10/09/2010] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Gene therapy has the potential to counter problems that still hamper standard HIV antiretroviral therapy, such as toxicity, patient adherence and the development of resistance. RNA interference can suppress HIV replication as a gene therapeutic via expressed short hairpin RNAs (shRNAs). It is now clear that multiple shRNAs will likely be required to suppress infection and prevent the emergence of resistant virus. RESULTS We have developed the first biologically relevant stochastic model in which multiple shRNAs are introduced into CD34+ hematopoietic stem cells. This model has been used to track the production of gene-containing CD4+ T cells, the degree of HIV infection, and the development of HIV resistance in lymphoid tissue for 13 years. In this model, we found that at least four active shRNAs were required to suppress HIV infection/replication effectively and prevent the development of resistance. The inhibition of incoming virus was shown to be critical for effective treatment. The low potential for resistance development that we found is largely due to a pool of replicating wild-type HIV that is maintained in non-gene containing CD4+ T cells. This wild-type HIV effectively out-competes emerging viral strains, maintaining the viral status quo. CONCLUSIONS The presence of a group of cells that lack the gene therapeutic and is available for infection by wild-type virus appears to mitigate the development of resistance observed with systemic antiretroviral therapy.
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Affiliation(s)
- Tanya Lynn Applegate
- Johnson and Johnson Research Pty Ltd, Level 4 Biomedical Building, 1 Central Avenue, Australian Technology Park, Eveleigh, NSW, 1430, Australia
- The National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Level 9 Lowy Packer Building, 405 Liverpool St, Darlinghurst, NSW, 2010, Australia
| | - Donald John Birkett
- Johnson and Johnson Research Pty Ltd, Level 4 Biomedical Building, 1 Central Avenue, Australian Technology Park, Eveleigh, NSW, 1430, Australia
- 9 Raglan St, Mosman, NSW, 2088, Australia
| | - Glen John Mcintyre
- Johnson and Johnson Research Pty Ltd, Level 4 Biomedical Building, 1 Central Avenue, Australian Technology Park, Eveleigh, NSW, 1430, Australia
- School of Molecular and Microbial Biosciences, School of Biological Sciences, University of Sydney, NSW, 2006, Australia
| | - Angel Belisario Jaramillo
- Johnson and Johnson Research Pty Ltd, Level 4 Biomedical Building, 1 Central Avenue, Australian Technology Park, Eveleigh, NSW, 1430, Australia
- Cell and Molecular Therapies, Royal Prince Alfred Hospital Missenden Road, Camperdown, NSW, 2050, Australia
| | - Geoff Symonds
- Johnson and Johnson Research Pty Ltd, Level 4 Biomedical Building, 1 Central Avenue, Australian Technology Park, Eveleigh, NSW, 1430, Australia
- Faculty of Medicine, Level 8, Lowy Packer Building, 405 Liverpool St, Darlinghurst, NSW, 2010, Australia
| | - John Michael Murray
- The National Centre in HIV Epidemiology and Clinical Research, University of New South Wales, Level 9 Lowy Packer Building, 405 Liverpool St, Darlinghurst, NSW, 2010, Australia
- School of Mathematics and Statistics, University of New South Wales, Sydney, NSW, 2052, Australia
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Shen L, Rabi SA, Siliciano RF. A novel method for determining the inhibitory potential of anti-HIV drugs. Trends Pharmacol Sci 2010; 30:610-6. [PMID: 19837466 DOI: 10.1016/j.tips.2009.09.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 09/06/2009] [Accepted: 09/07/2009] [Indexed: 11/26/2022]
Abstract
In the absence of cure, most HIV-1-infected individuals will require lifelong treatment. It is therefore essential to optimize highly active antiretroviral therapy. Recent research has shown that the slope parameter or Hill coefficient, which describes the steepness of a dose-response curve, is a critical missing dimension in the evaluation of the activity of antiviral drugs. Based on this finding, instantaneous inhibitory potential (IIP) has been derived as a new measure of antiviral drug activity. IIP incorporates the slope parameter and thus is a more accurate pharmacodynamic measure of antiviral activity than current measures such as IC(50) and inhibitory quotient. Determining how to use IIP to predict the in vivo efficacy of anti-HIV-1 drugs is nevertheless important. This article discusses recent advances in in vitro measures of antiviral activity and the therapeutic implications of the dose-response curve slope and IIP.
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Affiliation(s)
- Lin Shen
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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Rhee SY, Fessel WJ, Liu TF, Marlowe NM, Rowland CM, Rode RA, Vandamme AM, Van Laethem K, Brun-Vezinet F, Calvez V, Taylor J, Hurley L, Horberg M, Shafer RW. Predictive value of HIV-1 genotypic resistance test interpretation algorithms. J Infect Dis 2009; 200:453-63. [PMID: 19552527 PMCID: PMC4774893 DOI: 10.1086/600073] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Interpreting human immunodeficiency virus type 1 (HIV-1) genotypic drug-resistance test results is challenging for clinicians treating HIV-1-infected patients. Multiple drug-resistance interpretation algorithms have been developed, but their predictive value has rarely been evaluated using contemporary clinical data sets. METHODS We examined the predictive value of 4 algorithms at predicting virologic response (VR) during 734 treatment-change episodes (TCEs). VR was defined as attaining plasma HIV-1 RNA levels below the limit of quantification. Drug-specific genotypic susceptibility scores (GSSs) were calculated by applying each algorithm to the baseline genotype. Weighted GSSs were calculated by multiplying drug-specific GSSs by antiretroviral (ARV) potency factors. Regimen-specific GSSs (rGSSs) were calculated by adding unweighted or weighted drug-specific GSSs for each salvage therapy ARV. The predictive value of rGSSs were estimated by use of multivariate logistic regression. RESULTS Of 734 TCEs, 475 (65%) were associated with VR. The rGSSs for the 4 algorithms were the variables most strongly predictive of VR. The adjusted rGSS odds ratios ranged from 1.6 to 2.2 (P < .001). Using 10-fold cross-validation, the averaged area under the receiver operating characteristic curve for all algorithms increased from 0.76 with unweighted rGSSs to 0.80 with weighted rGSSs. CONCLUSIONS Unweighted and weighted rGSSs of 4 genotypic resistance algorithms were the strongest independent predictors of VR. Optimizing ARV weighting may further improve VR predictions.
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Affiliation(s)
- Soo-Yon Rhee
- Division of Infectious Diseases, Dept. of Medicine, Stanford University, Stanford, CA 94305, USA.
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The impact of individual human immunodeficiency virus type 1 protease mutations on drug susceptibility is highly influenced by complex interactions with the background protease sequence. J Virol 2009; 83:9512-20. [PMID: 19587054 DOI: 10.1128/jvi.00291-09] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The requirement for multiple mutations for protease inhibitor (PI) resistance necessitates a better understanding of the molecular basis of resistance development. The novel bioinformatics resistance determination approach presented here elaborates on genetic profiles observed in clinical human immunodeficiency virus type 1 (HIV-1) isolates. Synthetic protease sequences were cloned in a wild-type HIV-1 background to generate a large number of close variants, covering 69 mutation clusters between multi-PI-resistant viruses and their corresponding genetically closely related, but PI-susceptible, counterparts. The vast number of mutants generated facilitates a profound and broad analysis of the influence of the background on the effect of individual PI resistance-associated mutations (PI-RAMs) on PI susceptibility. Within a set of viruses, all PI-RAMs that differed between susceptible and resistant viruses were varied while maintaining the background sequence from the resistant virus. The PI darunavir was used to evaluate PI susceptibility. Single sets allowed delineation of the impact of individual mutations on PI susceptibility, as well as the influence of PI-RAMs on one another. Comparing across sets, it could be inferred how the background influenced the interaction between two mutations, in some cases even changing antagonistic relationships into synergistic ones or vice versa. The approach elaborates on patient data and demonstrates how the specific mutational background greatly influences the impact of individual mutations on PI susceptibility in clinical patterns.
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Domingo E, Grande-Pérez A, Martín V. Future prospects for the treatment of rapidly evolving viral pathogens: insights from evolutionary biology. Expert Opin Biol Ther 2008; 8:1455-60. [DOI: 10.1517/14712598.8.10.1455] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Abstract
Accumulating data suggest that not all human immunodeficiency virus (HIV)-1–specific immune responses are equally effective at controlling HIV-1 replication. A new study now demonstrates that multiple immune-driven sequence polymorphisms in the highly conserved HIV-1 Gag region of transmitted viruses are associated with reduced viral replication in newly infected humans. These data suggest that targeting these and other conserved viral regions may be the key to developing an effective HIV-1 vaccine.
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Affiliation(s)
- Todd M Allen
- Partners AIDS Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA.
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