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García-Crespo C, Francisco-Recuero I, Gallego I, Camblor-Murube M, Soria ME, López-López A, de Ávila AI, Madejón A, García-Samaniego J, Domingo E, Sánchez-Pacheco A, Perales C. Hepatitis C virus fitness can influence the extent of infection-mediated epigenetic modifications in the host cells. Front Cell Infect Microbiol 2023; 13:1057082. [PMID: 36992689 PMCID: PMC10040758 DOI: 10.3389/fcimb.2023.1057082] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 02/28/2023] [Indexed: 03/14/2023] Open
Abstract
IntroductionCellular epigenetic modifications occur in the course of viral infections. We previously documented that hepatitis C virus (HCV) infection of human hepatoma Huh-7.5 cells results in a core protein-mediated decrease of Aurora kinase B (AURKB) activity and phosphorylation of Serine 10 in histone H3 (H3Ser10ph) levels, with an affectation of inflammatory pathways. The possible role of HCV fitness in infection-derived cellular epigenetic modifications is not known.MethodsHere we approach this question using HCV populations that display a 2.3-fold increase in general fitness (infectious progeny production), and up to 45-fold increase of the exponential phase of intracellular viral growth rate, relative to the parental HCV population.ResultsWe show that infection resulted in a HCV fitness-dependent, average decrease of the levels of H3Ser10ph, AURKB, and histone H4 tri-methylated at Lysine 20 (H4K20m3) in the infected cell population. Remarkably, the decrease of H4K20m3, which is a hallmark of cellular transformation, was significant upon infection with high fitness HCV but not upon infection with basal fitness virus.DiscussionHere we propose two mechanisms ─which are not mutually exclusive─ to explain the effect of high viral fitness: an early advance in the number of infected cells, or larger number of replicating RNA molecules per cell. The implications of introducing HCV fitness as an influence in virus-host interactions, and for the course of liver disease, are warranted. Emphasis is made in the possibility that HCV-mediated hepatocellular carcinoma may be favoured by prolonged HCV infection of a human liver, a situation in which viral fitness is likely to increase.
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Affiliation(s)
- Carlos García-Crespo
- Department of Interactions with the Environment, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
| | - Irene Francisco-Recuero
- Department de Biochemistry, UAM, Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | - Isabel Gallego
- Department of Interactions with the Environment, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
| | - Marina Camblor-Murube
- Department de Biochemistry, UAM, Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | - María Eugenia Soria
- Department of Interactions with the Environment, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
- Department of Clinical Microbiology, IIS-Fundación Jiménez Díaz, UAM, Madrid, Spain
| | - Ana López-López
- Department de Biochemistry, UAM, Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
| | - Ana Isabel de Ávila
- Department of Interactions with the Environment, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
| | - Antonio Madejón
- Department of Interactions with the Environment, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
- Hepatology Unit Hospital Universitario La Paz/Carlos III, Instituto de Investigación Sanitaria “La Paz”, Madrid, Spain
| | - Javier García-Samaniego
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
- Hepatology Unit Hospital Universitario La Paz/Carlos III, Instituto de Investigación Sanitaria “La Paz”, Madrid, Spain
| | - Esteban Domingo
- Department of Interactions with the Environment, Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
- *Correspondence: Esteban Domingo, ; Aurora Sánchez-Pacheco, ; Celia Perales,
| | - Aurora Sánchez-Pacheco
- Department de Biochemistry, UAM, Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, Madrid, Spain
- *Correspondence: Esteban Domingo, ; Aurora Sánchez-Pacheco, ; Celia Perales,
| | - Celia Perales
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain
- Department of Clinical Microbiology, IIS-Fundación Jiménez Díaz, UAM, Madrid, Spain
- Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain
- *Correspondence: Esteban Domingo, ; Aurora Sánchez-Pacheco, ; Celia Perales,
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2
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Rindler AE, Kuster H, Neumann K, Leemann C, Braun DL, Metzner KJ, Günthard HF. A Novel High Throughput, Parallel Infection Assay for Determining the Replication Capacities of 346 Primary HIV-1 Isolates of the Zurich Primary HIV-1 Infection Study in Primary Cells. Viruses 2021; 13:404. [PMID: 33806576 PMCID: PMC8000554 DOI: 10.3390/v13030404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 03/02/2021] [Accepted: 03/02/2021] [Indexed: 12/24/2022] Open
Abstract
HIV-1 replication capacity is an important characteristic to understand the replication competence of single variants or virus populations. It can further aid in the understanding of HIV-1 pathogenicity, disease progression, and drug resistance mutations. To effectively study RC, many assays have been established. However, there is still demand for a high throughput replication capacity assay using primary cells which is robust and reproducible. In this study, we established such an assay and validated it using 346 primary HIV-1 isolates from patients enrolled in the Zurich Primary HIV Infection study (ZPHI) and two control viruses, HIV-1 JR-CSFWT and HIV-1 JR-CSFK65R_M184V. Replication capacity was determined by measuring the viral growth on PBMCs over 10 days by longitudinally transferring cell culture supernatant to TZM-bl reporter cells. By utilizing the TZM-bl luciferase reporter assay, we determined replication capacity by measuring viral infectivity. The simplicity of the experimental setup allowed for all 346 primary HIV-1 isolates to be replicated at one time. Although the infectious input dose for each virus was normalized, a broad range of replication capacity values over 4 logs was observed. The approach was confirmed by two repeated experiments and we demonstrated that the reproducibility of the replication capacity values is statistically comparable between the two separate experiments. In summary, these results endorse our high throughput replication capacity assay as reproducible and robust and can be utilized for large scale HIV-1 replication capacity experiments in primary cells.
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Affiliation(s)
- Audrey E. Rindler
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
- Life Sciences Graduate School, University of Zürich, 8057 Zürich, Switzerland
| | - Herbert Kuster
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
| | - Kathrin Neumann
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
| | - Christine Leemann
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
| | - Dominique L. Braun
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
| | - Karin J. Metzner
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
| | - Huldrych F. Günthard
- Division of Infectious Diseases and Hospital Epidemiology, University Hospital Zürich, 8091 Zürich, Switzerland; (A.E.R.); (H.K.); (K.N.); (C.L.); (D.L.B.)
- Institute of Medical Virology, University of Zürich, 8057 Zürich, Switzerland
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3
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Gomes STM, da Silva Graça Amoras E, Gomes ÉR, Queiroz MAF, Júnior ECS, de Vasconcelos Massafra JM, da Silva Lemos P, Júnior JLV, Ishak R, Vallinoto ACR. Immune escape mutations in HIV-1 controllers in the Brazilian Amazon region. BMC Infect Dis 2020; 20:546. [PMID: 32711474 PMCID: PMC7382849 DOI: 10.1186/s12879-020-05268-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 07/16/2020] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Human immunodeficiency virus (HIV-1) infection is characterized by high viral replication and a decrease in CD4+ T cells (CD4+TC), resulting in AIDS, which can lead to death. In elite controllers and viremia controllers, viral replication is naturally controlled, with maintenance of CD4+TC levels without the use of antiretroviral therapy (ART). METHODS The aim of the present study was to describe virological and immunological risk factors among HIV-1-infected individuals according to characteristics of progression to AIDS. The sample included 30 treatment-naive patients classified into three groups based on infection duration (> 6 years), CD4+TC count and viral load: (i) 2 elite controllers (ECs), (ii) 7 viremia controllers (VCs) and (iii) 21 nonviremia controllers (NVCs). Nested PCR was employed to amplify the virus genome, which was later sequenced using the Ion PGM platform for subtyping and analysis of immune escape mutations. RESULTS Viral samples were classified as HIV-1 subtypes B and F. Greater selection pressure on mutations was observed in the group of viremia controllers, with a higher frequency of immunological escape mutations in the genes investigated, including two new mutations in gag. The viral sequences of viremia controllers and nonviremia controllers did not differ significantly regarding the presence of immune escape mutations. CONCLUSION The results suggest that progression to AIDS is not dependent on a single variable but rather on a set of characteristics and pressures exerted by virus biology and interactions with immunogenetic host factors.
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Affiliation(s)
- Samara Tatielle Monteiro Gomes
- Laboratory of Virology, Biological Science Institute, Federal University of Pará (ICB/UFPA), Ananindeua, Brazil
- Graduate Program in Biology of Infectious and Parasitic Agents, Biological Science Institute, Federal University of Pará, Ananindeua, Brazil
| | | | - Érica Ribeiro Gomes
- Laboratory of Virology, Biological Science Institute, Federal University of Pará (ICB/UFPA), Ananindeua, Brazil
| | - Maria Alice Freitas Queiroz
- Laboratory of Virology, Biological Science Institute, Federal University of Pará (ICB/UFPA), Ananindeua, Brazil
| | - Edivaldo Costa Sousa Júnior
- Health Surveillance Department, Ministry of Health (IEC-SVS/MS), Evandro Chagas Institute, Ananindeua, Brazil
| | | | - Poliana da Silva Lemos
- Health Surveillance Department, Ministry of Health (IEC-SVS/MS), Evandro Chagas Institute, Ananindeua, Brazil
| | - João Lídio Vianez Júnior
- Health Surveillance Department, Ministry of Health (IEC-SVS/MS), Evandro Chagas Institute, Ananindeua, Brazil
| | - Ricardo Ishak
- Laboratory of Virology, Biological Science Institute, Federal University of Pará (ICB/UFPA), Ananindeua, Brazil
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Silver N, Paynter M, McAllister G, Atchley M, Sayir C, Short J, Winner D, Alouani DJ, Sharkey FH, Bergefall K, Templeton K, Carrington D, Quiñones-Mateu ME. Characterization of minority HIV-1 drug resistant variants in the United Kingdom following the verification of a deep sequencing-based HIV-1 genotyping and tropism assay. AIDS Res Ther 2018; 15:18. [PMID: 30409215 PMCID: PMC6223033 DOI: 10.1186/s12981-018-0206-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Accepted: 10/30/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND The widespread global access to antiretroviral drugs has led to considerable reductions in morbidity and mortality but, unfortunately, the risk of virologic failure increases with the emergence, and potential transmission, of drug resistant viruses. Detecting and quantifying HIV-1 drug resistance has therefore become the standard of care when designing new antiretroviral regimens. The sensitivity of Sanger sequencing-based HIV-1 genotypic assays is limited by its inability to identify minority members of the quasispecies, i.e., it only detects variants present above ~ 20% of the viral population, thus, failing to detect minority variants below this threshold. It is clear that deep sequencing-based HIV-1 genotyping assays are an important step change towards accurately monitoring HIV-infected individuals. METHODS We implemented and verified a clinically validated HIV-1 genotyping assay based on deep sequencing (DEEPGEN™) in two clinical laboratories in the United Kingdom: St. George's University Hospitals Healthcare NHS Foundation Trust (London) and at NHS Lothian (Edinburgh), to characterize minority HIV-1 variants in 109 plasma samples from ART-naïve or -experienced individuals. RESULTS Although subtype B HIV-1 strains were highly prevalent (44%, 48/109), most individuals were infected with non-B subtype viruses (i.e., A1, A2, C, D, F1, G, CRF02_AG, and CRF01_AE). DEEPGEN™ was able to accurately detect drug resistance-associated mutations not identified using standard Sanger sequencing-based tests, which correlated significantly with patient's antiretroviral treatment histories. A higher proportion of minority PI-, NRTI-, and NNRTI-resistance mutations was detected in NHS Lothian patients compared to individuals from St. George's, mainly M46I/L and I50 V (associated with PIs), D67 N, K65R, L74I, M184 V/I, and K219Q (NRTIs), and L100I (NNRTIs). Interestingly, we observed an inverse correlation between intra-patient HIV-1 diversity and CD4+ T cell counts in the NHS Lothian patients. CONCLUSIONS This is the first study evaluating the transition, training, and implementation of DEEPGEN™ between three clinical laboratories in two different countries. More importantly, we were able to characterize the HIV-1 drug resistance profile (including minority variants), coreceptor tropism, subtyping, and intra-patient viral diversity in patients from the United Kingdom, providing a rigorous foundation for basing clinical decisions on highly sensitive and cost-effective deep sequencing-based HIV-1 genotyping assays in the country.
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5
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Jackson L, Hunter J, Cele S, Ferreira IM, Young AC, Karim F, Madansein R, Dullabh KJ, Chen CY, Buckels NJ, Ganga Y, Khan K, Boulle M, Lustig G, Neher RA, Sigal A. Incomplete inhibition of HIV infection results in more HIV infected lymph node cells by reducing cell death. eLife 2018; 7:30134. [PMID: 29555018 PMCID: PMC5896883 DOI: 10.7554/elife.30134] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 03/08/2018] [Indexed: 12/22/2022] Open
Abstract
HIV has been reported to be cytotoxic in vitro and in lymph node infection models. Using a computational approach, we found that partial inhibition of transmissions of multiple virions per cell could lead to increased numbers of live infected cells. If the number of viral DNA copies remains above one after inhibition, then eliminating the surplus viral copies reduces cell death. Using a cell line, we observed increased numbers of live infected cells when infection was partially inhibited with the antiretroviral efavirenz or neutralizing antibody. We then used efavirenz at concentrations reported in lymph nodes to inhibit lymph node infection by partially resistant HIV mutants. We observed more live infected lymph node cells, but with fewer HIV DNA copies per cell, relative to no drug. Hence, counterintuitively, limited attenuation of HIV transmission per cell may increase live infected cell numbers in environments where the force of infection is high. The HIVvirus infects cells of the immune system. Once inside, it hijacks the cellular molecular machineries to make more copies of itself, which are then transmitted to new host cells. HIV eventually kills most cells it infects, either in the steps leading to the infection of the cell, or after the cell is already producing virus. HIV can spread between cells in two ways, known as cell-free or cell-to-cell. In the first, individual viruses are released from infected cells and move randomly through the body in the hope of finding new cells to infect. In the second, infected cells interact directly with uninfected cells. The second method is often much more successful at infecting new cells since they are exposed to multiple virus particles. HIV infections can be controlled by using combinations of antiretroviral drugs, such as efavirenz, to prevent the virus from making more of itself. With a high enough dose, the drugs can in theory completely stop HIV infections, unless the virus becomes resistant to treatment. However, some patients continue to use these drugs even after the virus they are infected with develops resistance. It is not clear what effect taking ineffective, or partially effective, drugs has on how HIV progresses. Using efavirenz, Jackson, Hunter et al. partially limited the spread of HIV between human cells grown in the laboratory. The experiments mirrored the situation where a partially resistant HIV strain spreads through the body. The results show that the success of cell-free infection is reduced as drug dose increases. Yet paradoxically, in cell-to-cell infection, the presence of drug caused more cells to become infected. This can be explained by the fact that, in cell-to-cell spread, each cell is exposed to multiple copies of the virus. The drug dose reduced the number of viral copies per cell without stopping the virus from infecting completely. The reduced number of viral copies per cell made it more likely that infected cells would survive the infection long enough to produce virus particles themselves. Viruses that can kill cells, such as HIV, must balance the need to make more of themselves against the speed that they kill their host cell to maximize the number of infected cells. If transmission between cells is too effective and too many virus particles are delivered to the new cell, the virus may not manage to infect new hosts before killing the old ones. These findings highlight this delicate balance. They also indicate a potential issue in using drugs to treat partially resistant virus strains. Without care, these treatments could increase the number of infected cells in the body, potentially worsening the effects of living with HIV.
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Affiliation(s)
- Laurelle Jackson
- Africa Health Research Institute, Durban, South Africa.,School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Jessica Hunter
- Africa Health Research Institute, Durban, South Africa.,School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Sandile Cele
- Africa Health Research Institute, Durban, South Africa
| | - Isabella Markham Ferreira
- Africa Health Research Institute, Durban, South Africa.,School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
| | - Andrew C Young
- Africa Health Research Institute, Durban, South Africa.,Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, United States
| | - Farina Karim
- Africa Health Research Institute, Durban, South Africa
| | - Rajhmun Madansein
- Department of Cardiothoracic Surgery, University of KwaZulu-Natal, Durban, South Africa.,Centre for the AIDS Programme of Research in South Africa, Durban, South Africa
| | - Kaylesh J Dullabh
- Department of Cardiothoracic Surgery, University of KwaZulu-Natal, Durban, South Africa
| | - Chih-Yuan Chen
- Department of Cardiothoracic Surgery, University of KwaZulu-Natal, Durban, South Africa
| | - Noel J Buckels
- Department of Cardiothoracic Surgery, University of KwaZulu-Natal, Durban, South Africa
| | - Yashica Ganga
- Africa Health Research Institute, Durban, South Africa
| | - Khadija Khan
- Africa Health Research Institute, Durban, South Africa
| | - Mikael Boulle
- Africa Health Research Institute, Durban, South Africa
| | - Gila Lustig
- Africa Health Research Institute, Durban, South Africa
| | - Richard A Neher
- Biozentrum, University of Basel, Basel, Switzerland.,SIB Swiss Institute of Bioinformatics, Basel, Switzerland
| | - Alex Sigal
- Africa Health Research Institute, Durban, South Africa.,School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa.,Max Planck Institute for Infection Biology, Berlin, Germany
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Gibson RM, Nickel G, Crawford M, Kyeyune F, Venner C, Nankya I, Nabulime E, Ndashimye E, Poon AFY, Salata RA, Kityo C, Mugyenyi P, Quiñones-Mateu ME, Arts EJ. Sensitive detection of HIV-1 resistance to Zidovudine and impact on treatment outcomes in low- to middle-income countries. Infect Dis Poverty 2017; 6:163. [PMID: 29202874 PMCID: PMC5716384 DOI: 10.1186/s40249-017-0377-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 11/22/2017] [Indexed: 12/31/2022] Open
Abstract
Background Thymidine analogs, namely AZT (Zidovudine or Retrovir™) and d4T (Stavudine or Zerit™) are antiretroviral drugs still employed in over 75% of first line combination antiretroviral therapy (cART) in Kampala, Uganda despite aversion to prescribing these drugs for cART in high income countries due in part to adverse events. For this study, we explored how the continued use of these thymidine analogs in cART could impact emergence of drug resistance and impact on future treatment success in Uganda, a low-income country. Methods We examined the drug resistance genotypes by Sanger sequencing of 262 HIV-infected patients failing a first line combined antiretroviral treatment containing either AZT or d4T, which represents approximately 5% of the patients at the Joint Clinical Research Center receiving a AZT or d4T containing treatment. Next generation sequencing (DEEPGEN™HIV) and multiplex oligonucleotide ligation assays (AfriPOLA) were then performed on a subset of patient samples to detect low frequency drug resistant mutations. CD4 cell counts, viral RNA loads, and treatment changes were analyzed in a cohort of treatment success and failures. Results Over 80% of patients failing first line AZT/d4T-containing cART had predicted drug resistance to 3TC (Lamivudine) and non-nucleoside RT inhibitors (NNRTIs) in the treatment regimen but only 45% had resistance AZT/d4T associated resistance mutations (TAMs). TAMs were however detected at low frequency within the patients HIV quasispecies (1–20%) in 21 of 34 individuals who were failing first-line AZT-containing cART and lacked TAMs by Sanger. Due to lack of TAMs by Sanger, AZT was typically maintained in second-line therapies and these patients had a low frequency of subsequent virologic success. Conclusions Our findings suggest that continued use of AZT and d4T in first-line treatment in low-to-middle income countries may lead to misdiagnosis of HIV-1 drug resistance and possibly enhance a succession of second- and third-line treatment failures. Electronic supplementary material The online version of this article (doi: 10.1186/s40249-017-0377-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Richard M Gibson
- Department of Microbiology and Immunology, University of Western Ontario, 1151 Richmond St., Dental Sciences Bldg., Rm 3014, London, Ontario, N6A 5C1, Canada
| | - Gabrielle Nickel
- Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Michael Crawford
- Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Fred Kyeyune
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA.,Department of Pathology, Case Western Reserve University, Cleveland, OH, USA
| | - Colin Venner
- Department of Microbiology and Immunology, University of Western Ontario, 1151 Richmond St., Dental Sciences Bldg., Rm 3014, London, Ontario, N6A 5C1, Canada
| | - Immaculate Nankya
- Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, OH, USA.,Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda.,Department of Pathology and Laboratory Medicine, University of Western Ontario, Kampala, Uganda
| | - Eva Nabulime
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Emmanuel Ndashimye
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Art F Y Poon
- Department of Pathology and Laboratory Medicine, University of Western Ontario, Kampala, Uganda
| | - Robert A Salata
- Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Cissy Kityo
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Peter Mugyenyi
- Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Miguel E Quiñones-Mateu
- Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, OH, USA.,Department of Pathology, Case Western Reserve University, Cleveland, OH, USA.,Center for AIDS Research Uganda Laboratories, Joint Clinical Research Centre, Kampala, Uganda
| | - Eric J Arts
- Department of Microbiology and Immunology, University of Western Ontario, 1151 Richmond St., Dental Sciences Bldg., Rm 3014, London, Ontario, N6A 5C1, Canada. .,TREAT, Joint Clinical Research Centre, Kampala, Uganda.
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7
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Weber J, Gibson RM, Sácká L, Strunin D, Hodek J, Weberová J, Pávová M, Alouani DJ, Asaad R, Rodriguez B, Lederman MM, Quiñones-Mateu ME. Impaired human immunodeficiency virus type 1 replicative fitness in atypical viremic non-progressor individuals. AIDS Res Ther 2017; 14:15. [PMID: 28331526 PMCID: PMC5359922 DOI: 10.1186/s12981-017-0144-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Accepted: 03/15/2017] [Indexed: 01/15/2023] Open
Abstract
Background Progression rates from initial HIV-1 infection to advanced AIDS vary significantly among infected individuals. A distinct subgroup of HIV-1-infected individuals—termed viremic non-progressors (VNP) or controllers—do not seem to progress to AIDS, maintaining high CD4+ T cell counts despite high levels of viremia for many years. Several studies have evaluated multiple host factors, including immune activation, trying to elucidate the atypical HIV-1 disease progression in these patients; however, limited work has been done to characterize viral factors in viremic controllers. Methods We analyzed HIV-1 isolates from three VNP individuals and compared the replicative fitness, near full-length HIV-1 genomes and intra-patient HIV-1 genetic diversity with viruses from three typical (TP) and one rapid (RP) progressor individuals. Results Viremic non-progressors and typical patients were infected for >10 years (range 10–17 years), with a mean CD4+ T-cell count of 472 cells/mm3 (442–529) and 400 cells/mm3 (126–789), respectively. VNP individuals had a less marked decline in CD4+ cells (mean −0.56, range −0.4 to −0.7 CD4+/month) than TP patients (mean −10.3, −8.2 to −13.1 CD4+/month). Interestingly, VNP individuals carried viruses with impaired replicative fitness, compared to HIV-1 isolates from the TP and RP patients (p < 0.05, 95% CI). Although analyses of the near full-length HIV-1 genomes showed no clear patterns of single-nucleotide polymorphisms (SNP) that could explain the decrease in replicative fitness, both the number of SNPs and HIV-1 population diversity correlated inversely with the replication capacity of the viruses (r = −0.956 and r = −0.878, p < 0.01, respectively). Conclusion It is likely that complex multifactorial parameters govern HIV-1 disease progression in each individual, starting with the infecting virus (phenotype, load, and quasispecies diversity) and the intrinsic ability of the host to respond to the infection. Here we analyzed a subset of viremic controller patients and demonstrated that similar to the phenomenon observed in patients with a discordant response to antiretroviral therapy (i.e., high CD4+ cell counts with detectable plasma HIV-1 RNA load), reduced viral replicative fitness seems to be linked to slow disease progression in these antiretroviral-naïve individuals. Electronic supplementary material The online version of this article (doi:10.1186/s12981-017-0144-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jan Weber
- 0000 0001 1015 3316grid.418095.1Institute of Organic Chemistry and Biochemistry v.v.i., Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Richard M Gibson
- 0000 0000 9149 4843grid.443867.aUniversity Hospital Translational Laboratory, University Hospitals Cleveland Medical Center, Cleveland, OH USA
| | - Lenka Sácká
- 0000 0001 1015 3316grid.418095.1Institute of Organic Chemistry and Biochemistry v.v.i., Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Dmytro Strunin
- 0000 0001 1015 3316grid.418095.1Institute of Organic Chemistry and Biochemistry v.v.i., Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Jan Hodek
- 0000 0001 1015 3316grid.418095.1Institute of Organic Chemistry and Biochemistry v.v.i., Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Jitka Weberová
- 0000 0001 1015 3316grid.418095.1Institute of Organic Chemistry and Biochemistry v.v.i., Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - Marcela Pávová
- 0000 0001 1015 3316grid.418095.1Institute of Organic Chemistry and Biochemistry v.v.i., Academy of Sciences of the Czech Republic, Flemingovo n. 2, 166 10 Prague 6, Czech Republic
| | - David J Alouani
- 0000 0000 9149 4843grid.443867.aUniversity Hospital Translational Laboratory, University Hospitals Cleveland Medical Center, Cleveland, OH USA
| | - Robert Asaad
- 0000 0001 2164 3847grid.67105.35Department of Medicine, Case Western Reserve University/University Hospitals Cleveland Medical Center, 10900 Euclid Avenue, Cleveland, OH 44106-7288 USA
| | - Benigno Rodriguez
- 0000 0001 2164 3847grid.67105.35Department of Medicine, Case Western Reserve University/University Hospitals Cleveland Medical Center, 10900 Euclid Avenue, Cleveland, OH 44106-7288 USA
| | - Michael M Lederman
- 0000 0001 2164 3847grid.67105.35Department of Medicine, Case Western Reserve University/University Hospitals Cleveland Medical Center, 10900 Euclid Avenue, Cleveland, OH 44106-7288 USA
| | - Miguel E Quiñones-Mateu
- 0000 0000 9149 4843grid.443867.aUniversity Hospital Translational Laboratory, University Hospitals Cleveland Medical Center, Cleveland, OH USA ; 0000 0001 2164 3847grid.67105.35Department of Medicine, Case Western Reserve University/University Hospitals Cleveland Medical Center, 10900 Euclid Avenue, Cleveland, OH 44106-7288 USA ; 0000 0001 2164 3847grid.67105.35Department of Pathology, Case Western Reserve University, Cleveland, OH USA
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Low-Frequency Drug Resistance in HIV-Infected Ugandans on Antiretroviral Treatment Is Associated with Regimen Failure. Antimicrob Agents Chemother 2016; 60:3380-97. [PMID: 27001818 DOI: 10.1128/aac.00038-16] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Accepted: 03/11/2016] [Indexed: 12/27/2022] Open
Abstract
Most patients failing antiretroviral treatment in Uganda continue to fail their treatment regimen even if a dominant drug-resistant HIV-1 genotype is not detected. In a recent retrospective study, we observed that approximately 30% of HIV-infected individuals in the Joint Clinical Research Centre (Kampala, Uganda) experienced virologic failure with a susceptible HIV-1 genotype based on standard Sanger sequencing. Selection of minority drug-resistant HIV-1 variants (not detectable by Sanger sequencing) under antiretroviral therapy pressure can lead to a shift in the viral quasispecies distribution, becoming dominant members of the virus population and eventually causing treatment failure. Here, we used a novel HIV-1 genotyping assay based on deep sequencing (DeepGen) to quantify low-level drug-resistant HIV-1 variants in 33 patients failing a first-line antiretroviral treatment regimen in the absence of drug-resistant mutations, as screened by standard population-based Sanger sequencing. Using this sensitive assay, we observed that 64% (21/33) of these individuals had low-frequency (or minority) drug-resistant variants in the intrapatient HIV-1 population, which correlated with treatment failure. Moreover, the presence of these minority HIV-1 variants was associated with higher intrapatient HIV-1 diversity, suggesting a dynamic selection or fading of drug-resistant HIV-1 variants from the viral quasispecies in the presence or absence of drug pressure, respectively. This study identified low-frequency HIV drug resistance mutations by deep sequencing in Ugandan patients failing antiretroviral treatment but lacking dominant drug resistance mutations as determined by Sanger sequencing methods. We showed that these low-abundance drug-resistant viruses could have significant consequences for clinical outcomes, especially if treatment is not modified based on a susceptible HIV-1 genotype by Sanger sequencing. Therefore, we propose to make clinical decisions using more sensitive methods to detect minority HIV-1 variants.
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9
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Contribution of human immunodeficiency virus type 1 minority variants to reduced drug susceptibility in patients on an integrase strand transfer inhibitor-based therapy. PLoS One 2014; 9:e104512. [PMID: 25110880 PMCID: PMC4128663 DOI: 10.1371/journal.pone.0104512] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2014] [Accepted: 07/09/2014] [Indexed: 12/13/2022] Open
Abstract
The role of HIV-1 minority variants on transmission, pathogenesis, and virologic failure to antiretroviral regimens has been explored; however, most studies of low-level HIV-1 drug-resistant variants have focused in single target regions. Here we used a novel HIV-1 genotypic assay based on deep sequencing, DEEPGEN (Gibson et al 2014 Antimicrob Agents Chemother 58∶2167) to simultaneously analyze the presence of minority variants carrying mutations associated with reduced susceptibility to protease (PR), reverse transcriptase (RT), and integrase strand transfer integrase inhibitors (INSTIs), as well as HIV-1 coreceptor tropism. gag-p2/NCp7/p1/p6/pol-PR/RT/INT and env/C2V3 PCR products were obtained from twelve heavily treatment-experienced patients experiencing virologic failure while participating in a 48-week dose-ranging study of elvitegravir (GS-US-183-0105). Deep sequencing results were compared with (i) virological response to treatment, (ii) genotyping based on population sequencing, (iii) phenotyping data using PhenoSense and VIRALARTS, and (iv) HIV-1 coreceptor tropism based on the phenotypic test VERITROP. Most patients failed the antiretroviral regimen with numerous pre-existing mutations in the PR and RT, and additionally newly acquired INSTI-resistance mutations as determined by population sequencing (mean 9.4, 5.3, and 1.4 PI- RTI-, and INSTI-resistance mutations, respectively). Interestingly, since DEEPGEN allows the accurate detection of amino acid substitutions at frequencies as low as 1% of the population, a series of additional drug resistance mutations were detected by deep sequencing (mean 2.5, 1.5, and 0.9, respectively). The presence of these low-abundance HIV-1 variants was associated with drug susceptibility, replicative fitness, and coreceptor tropism determined using sensitive phenotypic assays, enhancing the overall burden of resistance to all four antiretroviral drug classes. Further longitudinal studies based on deep sequencing tests will help to clarify (i) the potential impact of minority HIV-1 drug resistant variants in response to antiretroviral therapy and (ii) the importance of the detection of HIV minority variants in the clinical practice.
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10
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Lanxon-Cookson EC, Swain JV, Manocheewa S, Smith RA, Maust B, Kim M, Westfall D, Rolland M, Mullins JI. Factors affecting relative fitness measurements in pairwise competition assays of human immunodeficiency viruses. J Virol Methods 2013; 194:7-13. [PMID: 23933395 DOI: 10.1016/j.jviromet.2013.07.062] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Revised: 07/30/2013] [Accepted: 07/31/2013] [Indexed: 10/26/2022]
Abstract
Cell culture growth competition assays of human immunodeficiency virus type 1 (HIV-1) are used to estimate viral fitness and quantify the impact of mutations conferring drug resistance and immunological escape. A comprehensive study of growth competition assays was conducted and identified experimental parameters that can impact measurements of relative fitness including multiplicity of infection, viral input ratio, number, timing and interval of time points used to evaluate selective outgrowth, and the algorithm for calculating fitness values. An optimized protocol is developed here that is a multi-point growth competition assay that resolves reproducibly small differences in viral fitness. The optimized protocol uses an MOI of 0.005, a consistent ratio of mutant: parental viruses (70:30), and a multipoint [1+s 4,7] algorithm that uses data points within the logarithmic phase of viral growth for assessing fitness differences.
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Affiliation(s)
- Erinn C Lanxon-Cookson
- Department of Microbiology, University of Washington School of Medicine, Seattle, WA 98105-8070, United States
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11
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Resistance mutations outside the integrase coding region have an effect on human immunodeficiency virus replicative fitness but do not affect its susceptibility to integrase strand transfer inhibitors. PLoS One 2013; 8:e65631. [PMID: 23776513 PMCID: PMC3679210 DOI: 10.1371/journal.pone.0065631] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 04/25/2013] [Indexed: 11/19/2022] Open
Abstract
Most studies describing phenotypic resistance to integrase strand transfer inhibitors have analyzed viruses carrying only patient-derived HIV-1 integrase genes (INT-recombinant viruses). However, to date, many of the patients on INSTI-based treatment regimes, such as raltegravir (RAL), elvitegravir (EVG), and dolutegravir (DTG) are infected with multidrug-resistant HIV-1 strains. Here we analyzed the effect of drug resistance mutations in Gag (p2/NCp7/p1/p6), protease (PR), reverse transcriptase (RT), and integrase (IN) coding regions on susceptibility to INSTIs and viral replicative fitness using a novel HIV-1 phenotyping assay. Initial characterization based on site-directed mutant INSTI-resistant viruses confirmed the effect of a series of INSTI mutations on reduced susceptibility to EVG and RAL and viral replicative fitness (0.6% to 99% relative to the HIV-1NL4-3 control). Two sets of recombinant viruses containing a 3,428-bp gag-p2/NCp7/p1/p6/pol-PR/RT/IN (p2-INT) or a 1,088 bp integrase (INT) patient-derived fragment were constructed from plasma samples obtained from 27 virologic failure patients participating in a 48-week dose-ranging study of elvitegravir, GS-US-183-0105. A strong correlation was observed when susceptibility to EVG and RAL was assayed using p2-INT- vs. INT-recombinant viruses (Pearson coefficient correlation 0.869 and 0.918, P<0.0001 for EVG and RAL, respectively), demonstrating that mutations in the protease and RT have limited effect on susceptibility to these INSTIs. On the other hand, the replicative fitness of viruses harboring drug resistance mutations in PR, RT, and IN was generally impaired compared to viruses carrying only INSTI-resistance mutations. Thus, in the absence of drug pressure, drug resistance mutations in the PR and RT contribute to decrease the replicative fitness of the virus already impaired by mutations in the integrase. The use of recombinant viruses containing most or all HIV-1 regions targeted by antiretroviral drugs might be essential to understand the collective effect of epistatic interactions in multidrug-resistant viruses.
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12
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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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13
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HIV-1 conserved-element vaccines: relationship between sequence conservation and replicative capacity. J Virol 2013; 87:5461-7. [PMID: 23468488 DOI: 10.1128/jvi.03033-12] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To overcome the problem of HIV-1 variability, candidate vaccine antigens have been designed to be composed of conserved elements of the HIV-1 proteome. Such candidate vaccines could be improved with a better understanding of both HIV-1 evolutionary constraints and the fitness cost of specific mutations. We evaluated the in vitro fitness cost of 23 mutations engineered in the HIV-1 subtype B Gag-p24 Center-of-Tree (COT) protein through fitness competition assays. While some mutations at conserved sites exacted a high fitness cost, as expected under the assumption that the most conserved residue confers the highest fitness, there was no overall strong relationship between sequence conservation and replicative capacity. By comparing sites that have evolved since the beginning of the epidemic to those that have remain unchanged, we found that sites that have evolved over time were more likely to correspond to HLA-associated sites and that their mutation had limited fitness costs. Our data showed no transcendent link between high conservation and high fitness cost, indicating that merely focusing on conserved segments of HIV-1 would not be sufficient for a successful vaccine strategy. Nonetheless, a subset of sites exacted a high fitness cost upon mutation--these sites have been under selective pressure to change since the beginning of the epidemic but have proved virtually nonmutable and could constitute preferred targets for vaccine design.
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Jaramillo N, Domingo E, Muñoz-Egea MC, Tabarés E, Gadea I. Evidence of Muller's ratchet in herpes simplex virus type 1. J Gen Virol 2012; 94:366-375. [PMID: 23100362 DOI: 10.1099/vir.0.044685-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Population bottlenecks can have major effects in the evolution of RNA viruses, but their possible influence in the evolution of DNA viruses is largely unknown. Genetic and biological variation of herpes simplex virus type 1 (HSV-1) has been studied by subjecting 23 biological clones of the virus to 10 plaque-to-plaque transfers. In contrast to large population passages, plaque transfers led to a decrease in replicative capacity of HSV-1. Two out of a total of 23 clones did not survive to the last transfer in 143 TK(-) cells. DNA from three genomic regions (DNA polymerase, glycoprotein gD and thymidine kinase) from the initial and passaged clones was sequenced. Nucleotide substitutions were detected in the TK and gD genes, but not in the DNA polymerase gene. Assuming a uniform distribution of mutations along the genome, the average rate of fixation of mutations was about five mutations per viral genome and plaque transfer. This value is comparable to the range of values calculated for RNA viruses. Four plaque-transferred populations lost neurovirulence for mice, as compared with the corresponding initial clones. LD(50) values obtained with the populations subjected to serial bottlenecks were 4- to 67-fold higher than for their parental clones. These results equate HSV-1 with RNA viruses regarding fitness decrease as a result of plaque-to-plaque transfers, and show that population bottlenecks can modify the pathogenic potential of HSV-1. Implications for the evolution of complex DNA viruses are discussed.
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Affiliation(s)
- Nacarí Jaramillo
- Departamento de Medicina Preventiva Salud Pública y Microbiología, Facultad de Medicina, UAM, Madrid, Spain
| | - Esteban Domingo
- Centro de Investigación en Red de Enfermedades Hepáticas y Digestivas (CIBER ehd), Barcelona, Spain.,Centro de Biología Molecular 'Severo Ochoa' (Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid) Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
| | | | - Enrique Tabarés
- Departamento de Medicina Preventiva Salud Pública y Microbiología, Facultad de Medicina, UAM, Madrid, Spain
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15
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Emerging Viral Infections in Rheumatic Diseases. Semin Arthritis Rheum 2011; 41:236-46. [DOI: 10.1016/j.semarthrit.2011.01.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 01/27/2011] [Accepted: 01/28/2011] [Indexed: 02/06/2023]
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16
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Quasispecies as a matter of fact: viruses and beyond. Virus Res 2011; 162:203-15. [PMID: 21945638 PMCID: PMC7172439 DOI: 10.1016/j.virusres.2011.09.018] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2011] [Revised: 09/12/2011] [Accepted: 09/12/2011] [Indexed: 12/13/2022]
Abstract
We review the origins of the quasispecies concept and its relevance for RNA virus evolution, viral pathogenesis and antiviral treatment strategies. We emphasize a critical point of quasispecies that refers to genome collectivities as the unit of selection, and establish parallels between RNA viruses and some cellular systems such as bacteria and tumor cells. We refer also to tantalizing new observations that suggest quasispecies behavior in prions, perhaps as a result of the same quantum-mechanical indeterminations that underlie protein conformation and error-prone replication in genetic systems. If substantiated, these observations with prions could lead to new research on the structure-function relationship of non-nucleic acid biological molecules.
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Abstract
PURPOSE OF REVIEW Differential rates of disease progression are obviously multifactorial, but the virulence of the actual infecting virus is most frequently ignored as potential source of slow or rapid disease progression. In this review, the argument will be made that nearly all elite suppressors are infected by weak HIV-1 strain (in terms of replicative capacity). Whether this poor virus replication is the cause of elite suppression or the consequence of a strong immune response remains a leading question in the field. RECENT FINDINGS Although numerous research studies have related HIV-1 replicative capacity/fitness in tissue culture to virulence within patients, this review will focus on several recent and key discoveries on the important role of HIV-1 fitness in elite suppression. First, elite suppressors appear to harbor HIV-1 variants that encode Gag, Pol, and Env proteins that are less efficient than their counterparts of HIV-1 in typical/chronic progressors. Second, the actual HIV-1 clone(s) that establish acute infection may be less fit in patients who become elite controllers as compared with typical progressors. Finally, the fitness costs of cytotoxic T lymphocyte escape in HIV-1 may be easily compensated by secondary mutations if the infecting strain is capable of high replication kinetics and rapid evolution. A strain with weak replicative capacity might not compensate for fitness loss or even generate the initial escape mutations. SUMMARY A combination of good, anti-HIV-1 host genetics (e.g. HLA-B*57) along with infection by a 'whimpy' HIV-1 strain may be necessary for elite suppression, whereas only one of these may lead to slow progression and viremia.
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Mariam SH, Werngren J, Aronsson J, Hoffner S, Andersson DI. Dynamics of antibiotic resistant Mycobacterium tuberculosis during long-term infection and antibiotic treatment. PLoS One 2011; 6:e21147. [PMID: 21698208 PMCID: PMC3116863 DOI: 10.1371/journal.pone.0021147] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2011] [Accepted: 05/20/2011] [Indexed: 11/19/2022] Open
Abstract
For an infecting bacterium the human body provides several potential ecological niches with both internally (e.g. host immunity) and externally (e.g. antibiotic use) imposed growth restrictions that are expected to drive adaptive evolution in the bacterium, including the development of antibiotic resistance. To determine the extent and pattern of heterogeneity generated in a bacterial population during long-term antibiotic treatment, we examined in a monoclonal Mycobacterium tuberculosis infection antibiotic resistant mutants isolated from one patient during a 9-years period. There was a progressive accumulation of resistance mutations in the infecting clone. Furthermore, apparent clonal sweeps as well as co-existence of different resistant mutants were observed during this time, demonstrating that during treatment there is a high degree of dynamics in the bacterial population. These findings have important implications for diagnostics and treatment of drug resistant tuberculosis infections.
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Affiliation(s)
- Solomon H. Mariam
- Swedish Institute for Infectious Disease Control, Solna, Sweden
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Jim Werngren
- Swedish Institute for Infectious Disease Control, Solna, Sweden
| | - Joakim Aronsson
- Department of Infectious Diseases, County Hospital Ryhov, Jönköping, Sweden
| | - Sven Hoffner
- Swedish Institute for Infectious Disease Control, Solna, Sweden
| | - Dan I. Andersson
- Department of Infectious Diseases, County Hospital Ryhov, Jönköping, Sweden
- Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- * E-mail:
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Kwon OK, Choi JY, Kim EJ, Kim SS. Infectivity of Homologous Recombinant HIV-1 Pseudo-virus with Reverse Transcriptase Inhibitor-related Mutations from Highly Active Antiretroviral Therapy Experienced Patients. Osong Public Health Res Perspect 2011; 2:23-8. [PMID: 24159446 PMCID: PMC3766909 DOI: 10.1016/j.phrp.2011.04.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2011] [Revised: 03/22/2011] [Accepted: 03/31/2011] [Indexed: 11/04/2022] Open
Abstract
Objectives In this study, the viral fitness of pseudo-viruses with a drug-resistant site in the reverse transcriptase (RT) region of the genome was investigated. The pseudo-viruses were derived from highly active antiretroviral therapy (HAART)-experienced HIV/AIDS patients. Methods HIV-1 RNA was extracted from the plasma of HAART-experienced (KRB9149, KRB7021, KRC1097) and HAART-naïve (KRC5180, KRC5123) HIV-1 patients. The RT gene from the extracted viral RNA was amplified and the polymerase chain reaction product was cloned from the pHXB2Δ2-261 RT vector. C8166 and TZM-bl cell lines were used as the HIV-1 replication capacity measurement system. To quantify the infectivity of homologous recombinant HIV-1, the infectivity derived from each pseudo-virus was compared with the infectivity of the reference strain HXB2. Results Patient-derived HIV-1 was cotransfected into C8166 cells and the expression level of the p24 antigen was measured. The expression was high in the HIV-1 isolates from patients KRC5180 and KRB9149 and low in patients KRB7021, KRC5123, and KRC1097, when compared with the reference strain. The infectivity of the pseudo-virus measured in TZM-bl cells decreased in the order, reference strain HXB2 > KRC5180 > KRC5123 > KRB9149 > KRB7021 > KRC1097. Conclusion In this study, HIV-1 infectivity of the drug-resistant strain isolated from HAART-experienced patients with HIV/AIDS was found to be lower than the infectivity of the reference strain HXB2. This study provides useful data for the phenotypic susceptibility assay in HAART-experienced patients infected with HIV-1.
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Affiliation(s)
- Oh-Kyung Kwon
- Division of AIDS, Center for Immunology and Pathology, Korea National Institute of Health, Osong, Korea
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Novel method for simultaneous quantification of phenotypic resistance to maturation, protease, reverse transcriptase, and integrase HIV inhibitors based on 3'Gag(p2/p7/p1/p6)/PR/RT/INT-recombinant viruses: a useful tool in the multitarget era of antiretroviral therapy. Antimicrob Agents Chemother 2011; 55:3729-42. [PMID: 21628544 DOI: 10.1128/aac.00396-11] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Twenty-six antiretroviral drugs (ARVs), targeting five different steps in the life cycle of the human immunodeficiency virus type 1 (HIV-1), have been approved for the treatment of HIV-1 infection. Accordingly, HIV-1 phenotypic assays based on common cloning technology currently employ three, or possibly four, different recombinant viruses. Here, we describe a system to assess HIV-1 resistance to all drugs targeting the three viral enzymes as well as viral assembly using a single patient-derived, chimeric virus. Patient-derived p2-INT (gag-p2/NCp7/p1/p6/pol-PR/RT/IN) products were PCR amplified as a single fragment (3,428 bp) or two overlapping fragments (1,657 bp and 2,002 bp) and then recombined into a vector containing a near-full-length HIV-1 genome with the Saccharomyces cerevisiae uracil biosynthesis gene (URA3) replacing the 3,428 bp p2-INT segment (Dudley et al., Biotechniques 46:458-467, 2009). P2-INT-recombinant viruses were employed in drug susceptibility assays to test the activity of protease (PI), nucleoside/nucleotide reverse transcriptase (NRTI), nonnucleoside reverse transcriptase (NNRTI), and integrase strand-transfer (INSTI) inhibitors. Using a single standardized test (ViralARTS HIV), this new technology permits the rapid and automated quantification of phenotypic resistance for all known and candidate antiretroviral drugs targeting all viral enzymes (PR, RT, including polymerase and RNase H activities, and IN), some of the current and potential assembly inhibitors, and any drug targeting Pol or Gag precursor cleavage sites (relevant for PI and maturation inhibitors) This novel assay may be instrumental (i) in the development and clinical assessment of novel ARV drugs and (ii) to monitor patients failing prior complex treatment regimens.
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Jegede O, Khodyakova A, Chernov M, Weber J, Menéndez-Arias L, Gudkov A, Quiñones-Mateu ME. Identification of low-molecular weight inhibitors of HIV-1 reverse transcriptase using a cell-based high-throughput screening system. Antiviral Res 2011; 91:94-8. [PMID: 21600931 DOI: 10.1016/j.antiviral.2011.05.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2011] [Revised: 05/04/2011] [Accepted: 05/05/2011] [Indexed: 11/26/2022]
Abstract
A cell-based drug screening system that utilizes a green fluorescent protein (GFP)-tagged recombinant lentiviral vector has been used to screen a chemical library of 34,000 small molecules for antiretroviral compounds. Thirty-three initial hits were analyzed and four compounds were selected based on their anti-human immunodeficiency virus type 1 (HIV-1) activity (EC(50) values ranging from 0.17 to 1.9 μM) and low cellular toxicity (CC(50) values >50 μM). The four compounds blocked reverse transcription and were able to inhibit the replication of a panel of different HIV-1 strains, including non-B subtype and viruses resistant to different drug classes. Serial in vitro passages of HIV-1(B-HXB2) in the presence of increasing drug concentrations selected for viruses with reduced susceptibility. Mutations previously associated with resistance to non-nucleoside reverse transcriptase (RT) inhibitors (L100I and Y181C for CBL-17 and CBL-21, respectively) or linked to nucleoside analogue resistance (A62V for CBL-4.0 and CBL-4.1) were identified. Viruses with reduced susceptibility to CBL-17 and CBL-21 but not the ones resistant to CBL-4.0 or CBL-4.1 showed a decrease in replicative fitness. Interestingly, two of the small molecules (CBL-4.0 and CBL-4.1) are indolopyridinones that were previously described as nucleotide-competing RT inhibitors.
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Affiliation(s)
- Oyebisi Jegede
- Department of Molecular Genetics, Section of Virology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, USA
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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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Abstract
A number of virologic and environmental factors are involved in the emergence and re-emergence of viral disease. Viruses do not conservatively occupy a single and permanent ecological niche. Rather, due to their intrinsic capacity for genetic change, and to the evolvability of fitness levels, viruses display a potential to parasitize alternative host species. Mutation, recombination and genome segment reassortment, and combination of these molecular events, produce complex and phenotypically diverse populations of viruses, which constitute the raw material on which selection acts. The majority of emerging viral diseases of humans have a zoonotic origin. Sociologic and ecologic factors produce diverse and changing environments in which viral subpopulations have ample opportunities to be selected from intrinsically heterogeneous viral populations, particularly in the case of RNA viruses. In this manner, new human, animal and plant viruses have emerged periodically and, from all evidence, will continue to emerge. This article reviews some of the mechanisms that have been identified in viral emergence, with a focus on the importance of genetic variation of viruses, and on the general concept of biological complexity.
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Drug susceptibility of human immunodeficiency virus type 1-derived pseudoviruses from treatment-experienced patients to protease inhibitors and reverse transcriptase inhibitors, using a modified single-round assay. J Clin Virol 2010; 50:19-25. [PMID: 20970373 DOI: 10.1016/j.jcv.2010.09.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2010] [Revised: 09/17/2010] [Accepted: 09/20/2010] [Indexed: 11/22/2022]
Abstract
BACKGROUND Genotypic drug resistance assay has been the only method available to provide information related to drug resistance in South Korea since 1999. Phenotypic assay is also a useful method to predict a patient's state related to antiretroviral drug resistance. However, commercial systems and methods for phenotyping have not been introduced into South Korea. OBJECTIVES To establish and apply modified phenotypic drug susceptibility assay using treatment-experienced patients' derived HIV-1 in South Korea. STUDY DESIGN The genotypic drug resistance and phenotypic drug susceptibility of two different methods, Stanford HIV Drug Resistance Database (Stanford DB) and modified phenotypic drug susceptibility assay were compared especially focused on the HIV-1 protease (PR) and reverse transcriptase (RT) sequences. RESULTS There was some discordance in comparing drug susceptibility results (a modified drug susceptibility assay) with the predicted genotypic drug resistance (Stanford DB). Phenotypic drug resistance showed the following order for pseudoviruses from treatment-experienced patients infected with HIV/AIDS: Efavirenz (EFV, 21 to 1,319-fold change), Lamivudine (3TC, 31 to >189-fold change), Indinavir sulfate (IDV, 26 to 63-fold change), Amprenavir (APV, 4 to 35-fold change) and Zidovudine (AZT, 20 to 634-fold change). For patient KRC3221, the AZT-related phenotypic drug resistance was the greatest, with 634-fold change compared with the wild type. CONCLUSIONS Application of this modified phenotypic drug susceptibility assay is expected to help in predicting drug resistance as a guideline for clinicians to obtain a combined interpretation among genotyping, phenotyping and effective clinical treatments.
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Abstract
A large number of medically important viruses, including HIV, hepatitis C virus, and influenza, have RNA genomes. These viruses replicate with extremely high mutation rates and exhibit significant genetic diversity. This diversity allows a viral population to rapidly adapt to dynamic environments and evolve resistance to vaccines and antiviral drugs. For the last 30 years, quasispecies theory has provided a population-based framework for understanding RNA viral evolution. A quasispecies is a cloud of diverse variants that are genetically linked through mutation, interact cooperatively on a functional level, and collectively contribute to the characteristics of the population. Many predictions of quasispecies theory run counter to traditional views of microbial behavior and evolution and have profound implications for our understanding of viral disease. Here, we discuss basic principles of quasispecies theory and describe its relevance for our understanding of viral fitness, virulence, and antiviral therapeutic strategy.
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Affiliation(s)
- Adam S. Lauring
- Department of Medicine, University of California, San Francisco, San Francisco, California, United States of America
| | - Raul Andino
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
- * E-mail:
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van der Kuyl AC, Kozaczynska K, Ariën KK, Gali Y, Balázs VR, Dekker SJ, Zorgdrager F, Vanham G, Berkhout B, Cornelissen M. Analysis of infectious virus clones from two HIV-1 superinfection cases suggests that the primary strains have lower fitness. Retrovirology 2010; 7:60. [PMID: 20646276 PMCID: PMC2918528 DOI: 10.1186/1742-4690-7-60] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 07/20/2010] [Indexed: 11/30/2022] Open
Abstract
Background Two HIV-1 positive patients, L and P, participating in the Amsterdam Cohort studies acquired an HIV-1 superinfection within half a year from their primary HIV-1 infection (Jurriaans et al., JAIDS 2008, 47:69-73). The aim of this study was to compare the replicative fitness of the primary and superinfecting HIV-1 strains of both patients. The use of isolate-specific primer sets indicated that the primary and secondary strains co-exist in plasma at all time points after the moment of superinfection. Results Biological HIV-1 clones were derived from peripheral blood CD4 + T cells at different time point, and identified as the primary or secondary virus through sequence analysis. Replication competition assays were performed with selected virus pairs in PHA/IL-2 activated peripheral blood mononuclear cells (PBMC's) and analyzed with the Heteroduplex Tracking Assay (HTA) and isolate-specific PCR amplification. In both cases, we found a replicative advantage of the secondary HIV-1 strain over the primary virus. Full-length HIV-1 genomes were sequenced to find possible explanations for the difference in replication capacity. Mutations that could negatively affect viral replication were identified in the primary infecting strains. In patient L, the primary strain has two insertions in the LTR promoter, combined with a mutation in the tat gene that has been associated with decreased replication capacity. The primary HIV-1 strain isolated from patient P has two mutations in the LTR that have been associated with a reduced replication rate. In a luciferase assay, only the LTR from the primary virus of patient P had lower transcriptional activity compared with the superinfecting virus. Conclusions These preliminary findings suggest the interesting scenario that superinfection occurs preferentially in patients infected with a relatively attenuated HIV-1 isolate.
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Affiliation(s)
- Antoinette C van der Kuyl
- Laboratory of Experimental Virology, Department of Medical Microbiology, Centre for Infection and Immunity Amsterdam (CINIMA), Academic Medical Centre, University of Amsterdam, Amsterdam, The Netherlands.
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Unfinished stories on viral quasispecies and Darwinian views of evolution. J Mol Biol 2010; 397:865-77. [PMID: 20152841 DOI: 10.1016/j.jmb.2010.02.005] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2009] [Revised: 02/02/2010] [Accepted: 02/03/2010] [Indexed: 11/22/2022]
Abstract
Experimental evidence that RNA virus populations consist of distributions of mutant genomes, termed quasispecies, was first published 31 years ago. This work provided the earliest experimental support for a theory to explain a system that replicated with limited fidelity and to understand the self-organization and adaptability of early life forms on Earth. High mutation rates and quasispecies dynamics of RNA viruses are intimately related to both viral disease and antiviral treatment strategies. Moreover, the quasispecies concept is being applied to other biological systems such as cancer research in which cellular mutant spectra can be also detected. This review addresses some of the unanswered questions regarding viral and theoretical quasispecies concepts as well as more practical aspects concerning resistance to antiviral treatments and pathogenesis.
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Structure-function analysis of human immunodeficiency virus type 1 gp120 amino acid mutations associated with resistance to the CCR5 coreceptor antagonist vicriviroc. J Virol 2009; 83:12151-63. [PMID: 19776131 DOI: 10.1128/jvi.01351-09] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Vicriviroc (VCV) is a small-molecule CCR5 coreceptor antagonist currently in clinical trials for treatment of R5-tropic human immunodeficiency virus type 1 (HIV-1) infection. With this drug in development, identification of resistance mechanisms to VCV is needed to allow optimal outcomes in clinical practice. In this study we further characterized VCV resistance in a lab-adapted, VCV-resistant RU570 virus (RU570-VCV(res)). We show that K305R, R315Q, and K319T amino acid changes in the V3 loop, along with P437S in C4, completely reproduced the resistance phenotype in a chimeric ADA envelope containing the C2-V5 region from RU570 passage control gp120. The K305R amino acid change primarily impacted the degree of resistance, whereas K319T contributed to both resistance and virus infectivity. The P437S mutation in C4 had more influence on the relative degree of virus infectivity, while the R315Q mutation contributed to the virus concentration-dependent phenotypic resistance pattern observed for RU570-VCV(res). RU570-VCV(res) pseudovirus entry with VCV-bound CCR5 was dramatically reduced by Y10A, D11A, Y14A, and Y15A mutations in the N terminus of CCR5, whereas these mutations had less impact on entry in the absence of VCV. Notably, an additional Q315E/I317F substitution in the crown region of the V3 loop enhanced resistance to VCV, resulting in a stronger dependence on the N terminus for viral entry. By fitting the envelope mutations to a molecular model of a recently described docked N-terminal CCR5 peptide consisting of residues 2 to 15 in complex with HIV-1 gp120 CD4, potential new interactions in gp120 with the N terminus of CCR5 were uncovered. The cumulative results of this study suggest that as the RU570 VCV-resistant virus adapted to use the drug-bound receptor, it also developed an increased reliance on the N terminus of CCR5.
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Variable fitness impact of HIV-1 escape mutations to cytotoxic T lymphocyte (CTL) response. PLoS Pathog 2009; 5:e1000365. [PMID: 19343217 PMCID: PMC2659432 DOI: 10.1371/journal.ppat.1000365] [Citation(s) in RCA: 158] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2008] [Accepted: 03/05/2009] [Indexed: 12/16/2022] Open
Abstract
Human lymphocyte antigen (HLA)-restricted CD8(+) cytotoxic T lymphocytes (CTL) target and kill HIV-infected cells expressing cognate viral epitopes. This response selects for escape mutations within CTL epitopes that can diminish viral replication fitness. Here, we assess the fitness impact of escape mutations emerging in seven CTL epitopes in the gp120 Env and p24 Gag coding regions of an individual followed longitudinally from the time of acute HIV-1 infection, as well as some of these same epitopes recognized in other HIV-1-infected individuals. Nine dominant mutations appeared in five gp120 epitopes within the first year of infection, whereas all four mutations found in two p24 epitopes emerged after nearly two years of infection. These mutations were introduced individually into the autologous gene found in acute infection and then placed into a full-length, infectious viral genome. When competed against virus expressing the parental protein, fitness loss was observed with only one of the nine gp120 mutations, whereas four had no effect and three conferred a slight increase in fitness. In contrast, mutations conferring CTL escape in the p24 epitopes significantly decreased viral fitness. One particular escape mutation within a p24 epitope was associated with reduced peptide recognition and high viral fitness costs but was replaced by a fitness-neutral mutation. This mutation appeared to alter epitope processing concomitant with a reduced CTL response. In conclusion, CTL escape mutations in HIV-1 Gag p24 were associated with significant fitness costs, whereas most escape mutations in the Env gene were fitness neutral, suggesting a balance between immunologic escape and replicative fitness costs.
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CCR5- and CXCR4-tropic subtype C human immunodeficiency virus type 1 isolates have a lower level of pathogenic fitness than other dominant group M subtypes: implications for the epidemic. J Virol 2009; 83:5592-605. [PMID: 19297481 DOI: 10.1128/jvi.02051-08] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Human immunodeficiency virus type 1 (HIV-1) subtype C is the dominant subtype globally, due largely to the incidence of subtype C infections in sub-Saharan Africa and east Asia. We compared the relative replicative fitness (ex vivo) of the major (M) group of HIV-1 subtypes A, B, C, D, and CRF01_AE and group O isolates. To estimate pathogenic fitness, pairwise competitions were performed between CCR5-tropic (R5) or CXCR4-tropic (X4) virus isolates in peripheral blood mononuclear cells (PBMC). A general fitness order was observed among 33 HIV-1 isolates; subtype B and D HIV-1 isolates were slightly more fit than the subtype A and dramatically more fit than the 12 subtype C isolates. All group M isolates were more fit (ex vivo) than the group O isolates. To estimate ex vivo transmission fitness, a subset of primary HIV-1 isolates were examined in primary human explants from penile, cervical, and rectal tissues. Only R5 isolates and no X4 HIV-1 isolates could replicate in these tissues, whereas the spread to PM1 cells was dependent on active replication and passive virus transfer. In tissue competition experiments, subtype C isolates could compete with and, in some cases, even win over subtype A and D isolates. However, when the migratory cells from infected tissues were mixed with a susceptible cell line, the subtype C isolates were outcompeted by other subtypes, as observed in experiments with PBMC. These findings suggest that subtype C HIV-1 isolates might have equal transmission fitness but reduced pathogenic fitness relative to other group M HIV-1 isolates.
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Quiñones-Mateu ME, Moore-Dudley DM, Jegede O, Weber J, J Arts E. Viral drug resistance and fitness. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 2008; 56:257-96. [PMID: 18086415 DOI: 10.1016/s1054-3589(07)56009-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Anastassopoulou CG, Marozsan AJ, Matet A, Snyder AD, Arts EJ, Kuhmann SE, Moore JP. Escape of HIV-1 from a small molecule CCR5 inhibitor is not associated with a fitness loss. PLoS Pathog 2007; 3:e79. [PMID: 17542646 PMCID: PMC1885273 DOI: 10.1371/journal.ppat.0030079] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2007] [Accepted: 04/18/2007] [Indexed: 11/19/2022] Open
Abstract
Fitness is a parameter used to quantify how well an organism adapts to its environment; in the present study, fitness is a measure of how well strains of human immunodeficiency virus type 1 (HIV-1) replicate in tissue culture. When HIV-1 develops resistance in vitro or in vivo to antiretroviral drugs such as reverse transcriptase or protease inhibitors, its fitness is often impaired. Here, we have investigated whether the development of resistance in vitro to a small molecule CCR5 inhibitor, AD101, has an associated fitness cost. To do this, we developed a growth-competition assay involving dual infections with molecularly cloned viruses that are essentially isogenic outside the env genes under study. Real-time TaqMan quantitative PCR (QPCR) was used to quantify each competing virus individually via probes specific to different, phenotypically silent target sequences engineered within their vif genes. Head-to-head competition assays of env clones derived from the AD101 escape mutant isolate, the inhibitor-sensitive parental virus, and a passage control virus showed that AD101 resistance was not associated with a fitness loss. This observation is consistent with the retention of the resistant phenotype when the escape mutant was cultured for a total of 20 passages in the absence of the selecting compound. Amino acid substitutions in the V3 region of gp120 that confer complete AD101 resistance cause a fitness loss when introduced into an AD101-sensitive, parental clone; however, in the resistant isolate, changes elsewhere in env that occurred prior to the substitutions within V3 appear to compensate for the adverse effect of the V3 changes on replicative capacity. These in vitro studies may have implications for the development and management of resistance to other CCR5 inhibitors that are being evaluated clinically for the treatment of HIV-1 infection.
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Affiliation(s)
- Cleo G Anastassopoulou
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, United States of America
| | - Andre J Marozsan
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, United States of America
| | - Alexandre Matet
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, United States of America
| | - Amy D Snyder
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, United States of America
| | - Eric J Arts
- Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Shawn E Kuhmann
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, United States of America
- * To whom correspondence should be addressed. E-mail: (SEK); (JPM)
| | - John P Moore
- Department of Microbiology and Immunology, Weill Medical College of Cornell University, New York, New York, United States of America
- * To whom correspondence should be addressed. E-mail: (SEK); (JPM)
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Herrera M, García-Arriaza J, Pariente N, Escarmís C, Domingo E. Molecular basis for a lack of correlation between viral fitness and cell killing capacity. PLoS Pathog 2007; 3:e53. [PMID: 17432933 PMCID: PMC1851977 DOI: 10.1371/journal.ppat.0030053] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2006] [Accepted: 02/27/2007] [Indexed: 11/19/2022] Open
Abstract
The relationship between parasite fitness and virulence has been the object of experimental and theoretical studies often with conflicting conclusions. Here, we provide direct experimental evidence that viral fitness and virulence, both measured in the same biological environment provided by host cells in culture, can be two unrelated traits. A biological clone of foot-and-mouth disease virus acquired high fitness and virulence (cell killing capacity) upon large population passages in cell culture. However, subsequent plaque-to-plaque transfers resulted in profound fitness loss, but only a minimal decrease of virulence. While fitness-decreasing mutations have been mapped throughout the genome, virulence determinants-studied here with mutant and chimeric viruses-were multigenic, but concentrated on some genomic regions. Therefore, we propose a model in which viral virulence is more robust to mutation than viral fitness. As a consequence, depending on the passage regime, viral fitness and virulence can follow different evolutionary trajectories. This lack of correlation is relevant to current models of attenuation and virulence in that virus de-adaptation need not entail a decrease of virulence.
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Affiliation(s)
- Mónica Herrera
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
| | - Juan García-Arriaza
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
| | - Nonia Pariente
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
| | - Cristina Escarmís
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
| | - Esteban Domingo
- Centro de Biología Molecular “Severo Ochoa” (CSIC-UAM), Cantoblanco, Madrid, Spain
- * To whom correspondence should be addressed. E-mail:
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Henry KR, Weber J, Quiñones-Mateu ME, Arts EJ. The impact of viral and host elements on HIV fitness and disease progression. Curr HIV/AIDS Rep 2007; 4:36-41. [PMID: 17338859 DOI: 10.1007/s11904-007-0006-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Twenty-five years after the emergence of HIV onto the global scene, multiple advancements have been made in the understanding of HIV pathology. Thanks to the development of antiretroviral therapies, growing numbers of individuals with HIV infection experience slowed or halted acceleration to AIDS. Despite this, new HIV infections and AIDS-related morbidity and mortality are still common in the highly active antiretroviral therapy era. Recently, we and others have identified viral replicative fitness as a major determinant of HIV disease progression, which could have a major impact in the clinical setting. Therefore, in this review, we will discuss host and viral factors that affect viral fitness and its relationship on HIV pathogenesis.
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Affiliation(s)
- Kenneth R Henry
- Division of Infectious Diseases, BRB 1029, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, OH 44106, USA
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Natera S, Machuca C, Padrón-Nieves M, Romero A, Díaz E, Ponte-Sucre A. Leishmania spp.: proficiency of drug-resistant parasites. Int J Antimicrob Agents 2007; 29:637-42. [PMID: 17353113 DOI: 10.1016/j.ijantimicag.2007.01.004] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Revised: 01/12/2007] [Accepted: 01/16/2007] [Indexed: 11/29/2022]
Abstract
Leishmaniasis is a disease caused by at least 17 different species of protozoan Leishmania parasites and currently affects around 12 million people living mostly in tropical and subtropical areas. Failure to treat leishmaniasis successfully is often due to drug resistance. However, there are no cellular and molecular markers of chemoresistance against leishmanicidal drugs and the only reliable method for monitoring resistance of individual isolates is the in vitro amastigote/macrophage model. It is thus necessary to find cellular and molecular markers that can be used systematically to identify the drug-resistant phenotype of the infecting parasites. Until now, whether drug resistance in Leishmania compromises parasite proficiency, e.g. in terms of infectivity or metabolism, has not been systematically evaluated. Therefore, here we examine whether the physiological changes expressed by drug-resistant Leishmania reflect a modification of parasite vitality in drug-resistant compared with drug-sensitive parasites. Finally, the clinical implications of drug resistance in Leishmania are also discussed.
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Affiliation(s)
- Sonimar Natera
- Laboratorio de Fisiología Molecular, Instituto de Medicina Experimental, Facultad de Medicina, Universidad Central de Venezuela, Caracas, Venezuela
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Domingo E, Gomez J. Quasispecies and its impact on viral hepatitis. Virus Res 2007; 127:131-50. [PMID: 17349710 PMCID: PMC7125676 DOI: 10.1016/j.virusres.2007.02.001] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2006] [Revised: 01/11/2007] [Accepted: 02/03/2007] [Indexed: 12/17/2022]
Abstract
Quasispecies dynamics mediates adaptability of RNA viruses through a number of mechanisms reviewed in the present article, with emphasis on the medical implications for the hepatitis viruses. We discuss replicative and non-replicative molecular mechanisms of genome variation, modulating effects of mutant spectra, and several modes of viral evolution that can affect viral pathogenesis. Relevant evolutionary events include the generation of minority virus variants with altered functional properties, and alterations of mutant spectrum complexity that can affect disease progression or response to treatment. The widespread occurrence of resistance to antiviral drugs encourages new strategies to control hepatic viral disease such as combination therapies and lethal mutagenesis. In particular, ribavirin may be exerting in some cases its antiviral activity with participation of its mutagenic action. Despite many unanswered questions, here we document that quasispecies dynamics has provided an interpretation of the adaptability of the hepatitis viruses, with features conceptually similar to those observed with other RNA viruses, a reflection of the common underlying Darwinian principles.
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Affiliation(s)
- Esteban Domingo
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
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Abstract
During the rapid spread of HIV-1 in humans, the main (M) group of HIV-1 has evolved into ten distinct subtypes, undergone countless recombination events and diversified extensively. The impact of this extreme genetic diversity on the phenotype of HIV-1 has only recently become a research focus, but early findings indicate that the dominance of HIV-1 subtype C in the current epidemic might be related to the lower virulence of this subtype compared with other subtypes. Here, we explore whether HIV-1 has reached peak virulence or has already started the slow path to attenuation.
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Affiliation(s)
- Kevin K. Ariën
- the Department of Microbiology, HIV and Retrovirology Research Unit, Institute of Tropical Medicine, Nationalestraat 155, Antwerp, B2000 Belgium
- Present Address: the Department of Clinical Chemistry, Microbiology and Immunology, Faculty of Medicine and Health Sciences, Ghent University, De Pintelaan 185, Ghent, B-9000 Belgium
| | - Guido Vanham
- the Department of Microbiology, HIV and Retrovirology Research Unit, Institute of Tropical Medicine, Nationalestraat 155, Antwerp, B2000 Belgium
| | - Eric J. Arts
- the Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, 2109, Adelbert Rd, Cleveland, 44195 Ohio USA
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38
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Cong ME, Heneine W, García-Lerma JG. The fitness cost of mutations associated with human immunodeficiency virus type 1 drug resistance is modulated by mutational interactions. J Virol 2006; 81:3037-41. [PMID: 17192300 PMCID: PMC1865994 DOI: 10.1128/jvi.02712-06] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
It is generally accepted that the fitness cost of resistance mutations plays a role in the persistence of transmitted drug-resistant human immunodeficiency virus type 1 and that mutations that confer a high fitness cost are less able to persist in the absence of drug pressure. Here, we show that the fitness cost of reverse transcriptase (RT) mutations can vary within a 72-fold range. We also demonstrate that the fitness cost of M184V and K70R can be decreased or enhanced by other resistance mutations such as D67N and K219Q. We conclude that the persistence of transmitted RT mutants might range widely on the basis of fitness and that the modulation of fitness cost by mutational interactions will be a critical determinant of persistence.
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Affiliation(s)
- Mian-er Cong
- Division of HIV/AIDS Prevention, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, 1600 Clifton Road NE, Atlanta, GA 30333, USA
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39
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Abstract
Genomics is now a core element in the effort to develop a vaccine against HIV-1. Thanks to unprecedented progress in high-throughput genotyping and sequencing, in knowledge about genetic variation in humans, and in evolutionary genomics, it is finally possible to systematically search the genome for common genetic variants that influence the human response to HIV-1. The identification of such variants would help to determine which aspects of the response to the virus are the most promising targets for intervention. However, a key obstacle to progress remains the scarcity of appropriate human cohorts available for genomic research.
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Affiliation(s)
- Amalio Telenti
- Institute of Microbiology, University Hospital, University of Lausanne, 1011 Lausanne, Switzerland.
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40
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Njai HF, Gali Y, Vanham G, Clybergh C, Jennes W, Vidal N, Butel C, Mpoudi-Ngolle E, Peeters M, Ariën KK. The predominance of Human Immunodeficiency Virus type 1 (HIV-1) circulating recombinant form 02 (CRF02_AG) in West Central Africa may be related to its replicative fitness. Retrovirology 2006; 3:40. [PMID: 16817969 PMCID: PMC1525194 DOI: 10.1186/1742-4690-3-40] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2006] [Accepted: 07/03/2006] [Indexed: 11/30/2022] Open
Abstract
Background CRF02_AG is the predominant HIV strain circulating in West and West Central Africa. The aim of this study was to test whether this predominance is associated with a higher in vitro replicative fitness relative to parental subtype A and G viruses. Primary HIV-1 isolates (10 CRF02_AG, 5 subtype A and 5 subtype G) were obtained from a well-described Cameroonian cohort. Growth competition experiments were carried out at equal multiplicity of infection in activated T cells and monocyte-derived dendritic cells (MO-DC) in parallel. Results Dual infection/competition experiments in activated T cells clearly indicated that CRF02_AG isolates had a significant replication advantage over the subtype A and subtype G viruses. The higher fitness of CRF02_AG was evident for isolates from patients with CD4+ T cell counts >200 cells/μL (non-AIDS) or CD4+ T cell counts <200 cells/μL (AIDS), and was independent of the co-receptor tropism. In MO-DC cultures, CRF02_AG isolates showed a slightly but not significantly higher replication advantage compared to subtype A or G isolates. Conclusion We observed a higher ex vivo replicative fitness of CRF02_AG isolates compared to subtype A and G viruses from the same geographic region and showed that this was independent of the co-receptor tropism and irrespective of high or low CD4+ T cell count. This advantage in replicative fitness may contribute to the dominant spread of CRF02_AG over A and G subtypes in West and West Central Africa.
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Affiliation(s)
- Harr F Njai
- HIV and Retrovirology Research Unit, Department of Microbiology, Institute of Tropical Medicine, 155 Nationalestraat, B-2000 Antwerp, Belgium
| | - Youssef Gali
- HIV and Retrovirology Research Unit, Department of Microbiology, Institute of Tropical Medicine, 155 Nationalestraat, B-2000 Antwerp, Belgium
| | - Guido Vanham
- HIV and Retrovirology Research Unit, Department of Microbiology, Institute of Tropical Medicine, 155 Nationalestraat, B-2000 Antwerp, Belgium
- Department of Biomedical Sciences, Faculty of Pharmaceutical, Veterinary and Biomedical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerpen, Belgium
| | - Claude Clybergh
- HIV and Retrovirology Research Unit, Department of Microbiology, Institute of Tropical Medicine, 155 Nationalestraat, B-2000 Antwerp, Belgium
| | - Wim Jennes
- Immunology Unit, Department of Microbiology, Institute of Tropical Medicine, 155 Nationalestraat, B-2000 Antwerp, Belgium
| | - Nicole Vidal
- Institut de Recherche pour le Développement (IRD-UR 36) and Department of International Health, University of Montpellier, Montpellier, France
| | - Christelle Butel
- Institut de Recherche pour le Développement (IRD-UR 36) and Department of International Health, University of Montpellier, Montpellier, France
| | | | - Martine Peeters
- Institut de Recherche pour le Développement (IRD-UR 36) and Department of International Health, University of Montpellier, Montpellier, France
- Projet Presica, Hopital Militaire de Yaounde, BP 906, Yaounde, Cameroon
| | - Kevin K Ariën
- HIV and Retrovirology Research Unit, Department of Microbiology, Institute of Tropical Medicine, 155 Nationalestraat, B-2000 Antwerp, Belgium
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41
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Vercauteren J, Vandamme AM. Algorithms for the interpretation of HIV-1 genotypic drug resistance information. Antiviral Res 2006; 71:335-42. [PMID: 16782210 DOI: 10.1016/j.antiviral.2006.05.003] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2006] [Revised: 04/29/2006] [Accepted: 05/04/2006] [Indexed: 10/24/2022]
Abstract
Drug resistance testing has proven its use to guide treatment decisions in HIV-1 infected patients. Genotyping is the preferred technique for clinical drug resistance testing. Many factors complicate the interpretation of mutations towards therapy response, such that an interpretation system is necessary to help the clinical virologist. No consensus interpretation exists to date and experts often have quite different opinions. As a result, several algorithms for the interpretation of HIV-1 genotypic drug resistance information have been designed. Clinical evaluation of their genotypic interpretation is not always straightforward. We describe a few publicly available systems and their clinical evaluation. We also stress that in addition to drug resistance, for effective management of HIV infection the clinician needs to take into account all potential causes of treatment failure. Successful therapy heavily relies on the expertise of the clinician.
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Affiliation(s)
- Jurgen Vercauteren
- Clinical and Epidemiological Virology, Rega Institute for Medical Research, Katholieke Universiteit Leuven, Minderbroedersstraat 10, 3000 Leuven, Belgium
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