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Bimber BN, Sunshine J, McElfresh GW, Reed JS, Pathak R, Bateman KB, Hughes CM, Gilbride RM, Ford JC, Morrow D, Lifson JD, Sacha JB, Hansen SG, Picker LJ. Viral escape mutations do not account for non-protection from SIVmac239 challenge in RhCMV/SIV vaccinated rhesus macaques. Front Immunol 2024; 15:1444621. [PMID: 39170621 PMCID: PMC11336698 DOI: 10.3389/fimmu.2024.1444621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2024] [Accepted: 07/17/2024] [Indexed: 08/23/2024] Open
Abstract
Simian immunodeficiency virus (SIV) vaccines based upon 68-1 Rhesus Cytomegalovirus (RhCMV) vectors show remarkable protection against pathogenic SIVmac239 challenge. Across multiple independent rhesus macaque (RM) challenge studies, nearly 60% of vaccinated RM show early, complete arrest of SIVmac239 replication after effective challenge, whereas the remainder show progressive infection similar to controls. Here, we performed viral sequencing to determine whether the failure to control viral replication in non-protected RMs is associated with the acquisition of viral escape mutations. While low level viral mutations accumulated in all animals by 28 days-post-challenge, which is after the establishment of viral control in protected animals, the dominant circulating virus in virtually all unprotected RMs was nearly identical to the challenge stock, and there was no difference in mutation patterns between this cohort and unvaccinated controls. These data definitively demonstrate that viral mutation does not explain lack of viral control in RMs not protected by RhCMV/SIV vaccination. We further demonstrate that during chronic infection RhCMV/SIV vaccinated RMs do not acquire escape mutation in epitopes targeted by RhCMV/SIV, but instead display mutation in canonical MHC-Ia epitopes similar to unvaccinated RMs. This suggests that after the initial failure of viral control, unconventional T cell responses induced by 68-1 RhCMV/SIV vaccination do not exert strong selective pressure on systemically replicating SIV.
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Affiliation(s)
- Benjamin N. Bimber
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - Justine Sunshine
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - G. W. McElfresh
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Jason S. Reed
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Reese Pathak
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Katherine B. Bateman
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
| | - Colette M. Hughes
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - Roxanne M. Gilbride
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - Julia C. Ford
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - David Morrow
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - Jeffrey D. Lifson
- AIDS and Cancer Virus Program, Frederick National Laboratory, Frederick, MD, United States
| | - Jonah B. Sacha
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - Scott G. Hansen
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
| | - Louis J. Picker
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, OR, United States
- Vaccine and Gene Therapy Institute, Oregon Health and Science University, Beaverton, OR, United States
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2
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Domingo E, García-Crespo C, Soria ME, Perales C. Viral Fitness, Population Complexity, Host Interactions, and Resistance to Antiviral Agents. Curr Top Microbiol Immunol 2023; 439:197-235. [PMID: 36592247 DOI: 10.1007/978-3-031-15640-3_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Fitness of viruses has become a standard parameter to quantify their adaptation to a biological environment. Fitness determinations for RNA viruses (and some highly variable DNA viruses) meet with several uncertainties. Of particular interest are those that arise from mutant spectrum complexity, absence of population equilibrium, and internal interactions among components of a mutant spectrum. Here, concepts, fitness measurements, limitations, and current views on experimental viral fitness landscapes are discussed. The effect of viral fitness on resistance to antiviral agents is covered in some detail since it constitutes a widespread problem in antiviral pharmacology, and a challenge for the design of effective antiviral treatments. Recent evidence with hepatitis C virus suggests the operation of mechanisms of antiviral resistance additional to the standard selection of drug-escape mutants. The possibility that high replicative fitness may be the driver of such alternative mechanisms is considered. New broad-spectrum antiviral designs that target viral fitness may curtail the impact of drug-escape mutants in treatment failures. We consider to what extent fitness-related concepts apply to coronaviruses and how they may affect strategies for COVID-19 prevention and treatment.
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Affiliation(s)
- Esteban Domingo
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain. .,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain.
| | - Carlos García-Crespo
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - María Eugenia Soria
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040, Madrid, Spain
| | - Celia Perales
- Centro de Biología Molecular "Severo Ochoa" (CSIC-UAM), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Department of Clinical Microbiology, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Av. Reyes Católicos 2, 28040, Madrid, Spain.,Department of Molecular and Cell Biology, Centro Nacional de Biotecnología (CNB-CSIC), Consejo Superior de Investigaciones Científicas (CSIC), Campus de Cantoblanco, 28049, Madrid, Spain
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3
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Huang SH, McCann CD, Mota TM, Wang C, Lipkin SM, Jones RB. Have Cells Harboring the HIV Reservoir Been Immunoedited? Front Immunol 2019; 10:1842. [PMID: 31447850 PMCID: PMC6691121 DOI: 10.3389/fimmu.2019.01842] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Accepted: 07/22/2019] [Indexed: 01/05/2023] Open
Abstract
Immunoediting is an important concept in oncology, delineating the mechanisms through which tumors are selected for resistance to immune-mediated elimination. The recent emergence of immunotherapies, such as checkpoint inhibitors, as pillars of cancer therapy has intensified interest in immunoediting as a constraint limiting the efficacy of these approaches. Immunoediting manifests at a number of levels for different cancers, for example through the establishment of immunosuppressive microenvironments within solid tumors. Of particular interest to the current review, selection also occurs at the cellular level; and recent studies have revealed novel mechanisms by which tumor cells acquire intrinsic resistance to immune recognition and elimination. While the selection of escape mutations in viral epitopes by HIV-specific T cells, which is a hallmark of chronic HIV infection, can be considered a form of immunoediting, few studies have considered the possibility that HIV-infected cells themselves may parallel tumors in having differential intrinsic susceptibilities to immune-mediated elimination. Such selection, on the level of an infected cell, may not play a significant role in untreated HIV, where infection is propagated by high levels of cell-free virus produced by cells that quickly succumb to viral cytopathicity. However, it may play an unappreciated role in individuals treated with effective antiretroviral therapy where viral replication is abrogated. In this context, an "HIV reservoir" persists, comprising long-lived infected cells which undergo extensive and dynamic clonal expansion. The ability of these cells to persist in infected individuals has generally been attributed to viral latency, thought to render them invisible to immune recognition, and/or to their compartmentalization in anatomical sites that are poorly accessible to immune effectors. Recent data from ex vivo studies have led us to propose that reservoir-harboring cells may additionally have been selected for intrinsic resistance to CD8+ T cells, limiting their elimination even in the context of antigen expression. Here, we draw on knowledge from tumor immunoediting to discuss potential mechanisms by which clones of HIV reservoir-harboring cells may resist elimination by CD8+ T cells. The establishment of such parallels may provide a premise for testing therapeutics designed to sensitize tumor cells to immune-mediated elimination as novel approaches aimed at curing HIV infection.
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Affiliation(s)
- Szu-Han Huang
- Department of Medicine, Weill Cornell Medical College, New York, NY, United States
| | - Chase D. McCann
- Department of Medicine, Weill Cornell Medical College, New York, NY, United States
- Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, United States
| | - Talia M. Mota
- Department of Medicine, Weill Cornell Medical College, New York, NY, United States
| | - Chao Wang
- Department of Medicine, Weill Cornell Medical College, New York, NY, United States
| | - Steven M. Lipkin
- Department of Medicine, Weill Cornell Medical College, New York, NY, United States
| | - R. Brad Jones
- Department of Medicine, Weill Cornell Medical College, New York, NY, United States
- Program in Immunology and Microbial Pathogenesis, Weill Cornell Graduate School of Medical Sciences, New York, NY, United States
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High-Resolution Sequencing of Viral Populations during Early Simian Immunodeficiency Virus Infection Reveals Evolutionary Strategies for Rapid Escape from Emerging Env-Specific Antibody Responses. J Virol 2018; 92:JVI.01574-17. [PMID: 29343575 DOI: 10.1128/jvi.01574-17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 01/08/2018] [Indexed: 01/01/2023] Open
Abstract
Primate lentiviruses, including the human and simian immunodeficiency viruses (HIV and SIV), produce infections marked by persistent, ongoing viral replication. This occurs despite the presence of virus-specific adaptive immune responses, including antibodies targeting the viral envelope glycoprotein (Env), and evolution of antibody-escape variants is a well-documented feature of lentiviral infection. Here, we examined the evolutionary dynamics of the SIV env gene during early infection (≤29 weeks postinfection) in a cohort of four SIVmac251-infected rhesus macaques. We tracked env evolution during acute and early infection using frequent sampling and ultradeep sequencing of viral populations, capturing a transmission bottleneck and the subsequent reestablishment of Env diversity. A majority of changes in the gp120 subunit mapped to two short clusters, one in the first variable region (V1) and one in V4, while most changes in the gp41 subunit appeared in the cytoplasmic domain. Variation in V1 was dominated by short duplications and deletions of repetitive sequence, while variation in V4 was marked by short in-frame deletions and closely overlapping substitutions. The most common substitutions in both patches did not alter viral replicative fitness when tested using a highly sensitive, deep-sequencing-based competition assay. Our results, together with the observation that very similar or identical patterns of sequence evolution also occur in different macaque species infected with related but divergent strains of SIV, suggest that resistance to early, strain-specific anti-Env antibodies is the result of temporally and mutationally predictable pathways of escape that occur during the early stages of infection.IMPORTANCE The envelope glycoprotein (Env) of primate lentiviruses mediates entry by binding to host cell receptors followed by fusion of the viral membrane with the cell membrane. The exposure of Env complexes on the surface of the virion results in targeting by antibodies, leading to selection for virus escape mutations. We used the SIV/rhesus macaque model to track in vivo evolution of variation in Env during acute/early infection in animals with and without antibody responses to Env, uncovering remarkable variation in animals with antibody responses within weeks of infection. Using a deep-sequencing-based fitness assay, we found substitutions associated with antibody escape had little to no effect on inherent replicative capacity. The ability to readily propagate advantageous changes that incur little to no replicative fitness costs may be a mechanism to maintain continuous replication under constant immune selection, allowing the virus to persist for months to years in the infected host.
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5
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John M, Gaudieri S, Mallal S. Immunogenetics and Vaccination. HUMAN VACCINES 2017. [DOI: 10.1016/b978-0-12-802302-0.00005-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Arcia D, Acevedo-Sáenz L, Rugeles MT, Velilla PA. Role of CD8 + T Cells in the Selection of HIV-1 Immune Escape Mutations. Viral Immunol 2016; 30:3-12. [PMID: 27805477 DOI: 10.1089/vim.2016.0095] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human immunodeficiency virus type-1 (HIV-1) infection represents one of the biggest public health problems worldwide. The immune response, mainly the effector mechanisms mediated by CD8+ T cells, induces the selection of mutations that allows the virus to escape the immune control. These mutations are generally selected within CD8+ T cell epitopes restricted to human leukocyte antigen class I (HLA-I), leading to a decrease in the presentation and recognition of the epitope, decreasing the activation of CD8+ T cells. However, these mutations may also affect cellular processing of the peptide or recognition by the T cell receptor. Escape mutations often carry a negative impact in viral fitness that is partially or totally compensated by the selection of compensatory mutations. The selection of either escape mutations or compensatory mutations may negatively affect the course of the infection. In addition, these mutations are a major barrier for the development of new therapeutic strategies focused on the induction of specific CD8+ T cell responses.
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Affiliation(s)
- David Arcia
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA , Medellín, Colombia
| | - Liliana Acevedo-Sáenz
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA , Medellín, Colombia
| | - María Teresa Rugeles
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA , Medellín, Colombia
| | - Paula A Velilla
- Grupo Inmunovirología, Facultad de Medicina, Universidad de Antioquia UdeA , Medellín, Colombia
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7
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Martins MA, Tully DC, Cruz MA, Power KA, Veloso de Santana MG, Bean DJ, Ogilvie CB, Gadgil R, Lima NS, Magnani DM, Ejima K, Allison DB, Piatak M, Altman JD, Parks CL, Rakasz EG, Capuano S, Galler R, Bonaldo MC, Lifson JD, Allen TM, Watkins DI. Vaccine-Induced Simian Immunodeficiency Virus-Specific CD8+ T-Cell Responses Focused on a Single Nef Epitope Select for Escape Variants Shortly after Infection. J Virol 2015; 89:10802-20. [PMID: 26292326 PMCID: PMC4621113 DOI: 10.1128/jvi.01440-15] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 08/05/2015] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED Certain major histocompatibility complex class I (MHC-I) alleles (e.g., HLA-B*27) are enriched among human immunodeficiency virus type 1 (HIV-1)-infected individuals who suppress viremia without treatment (termed "elite controllers" [ECs]). Likewise, Mamu-B*08 expression also predisposes rhesus macaques to control simian immunodeficiency virus (SIV) replication. Given the similarities between Mamu-B*08 and HLA-B*27, SIV-infected Mamu-B*08(+) animals provide a model to investigate HLA-B*27-mediated elite control. We have recently shown that vaccination with three immunodominant Mamu-B*08-restricted epitopes (Vif RL8, Vif RL9, and Nef RL10) increased the incidence of elite control in Mamu-B*08(+) macaques after challenge with the pathogenic SIVmac239 clone. Furthermore, a correlate analysis revealed that CD8(+) T cells targeting Nef RL10 was correlated with improved outcome. Interestingly, this epitope is conserved between SIV and HIV-1 and exhibits a delayed and atypical escape pattern. These features led us to postulate that a monotypic vaccine-induced Nef RL10-specific CD8(+) T-cell response would facilitate the development of elite control in Mamu-B*08(+) animals following repeated intrarectal challenges with SIVmac239. To test this, we vaccinated Mamu-B*08(+) animals with nef inserts in which Nef RL10 was either left intact (group 1) or disrupted by mutations (group 2). Although monkeys in both groups mounted Nef-specific cellular responses, only those in group 1 developed Nef RL10-specific CD8(+) T cells. These vaccine-induced effector memory CD8(+) T cells did not prevent infection. Escape variants emerged rapidly in the group 1 vaccinees, and ultimately, the numbers of ECs were similar in groups 1 and 2. High-frequency vaccine-induced CD8(+) T cells focused on a single conserved epitope and therefore did not prevent infection or increase the incidence of elite control in Mamu-B*08(+) macaques. IMPORTANCE Since elite control of chronic-phase viremia is a classic example of an effective immune response against HIV/SIV, elucidating the basis of this phenomenon may provide useful insights into how to elicit such responses by vaccination. We have previously established that vaccine-induced CD8(+) T-cell responses against three immunodominant epitopes can increase the incidence of elite control in SIV-infected Mamu-B*08(+) rhesus macaques—a model of HLA-B*27-mediated elite control. Here, we investigated whether a monotypic vaccine-induced CD8(+) T-cell response targeting the conserved "late-escaping" Nef RL10 epitope can increase the incidence of elite control in Mamu-B*08(+) monkeys. Surprisingly, vaccine-induced Nef RL10-specific CD8(+) T cells selected for variants within days after infection and, ultimately, did not facilitate the development of elite control. Elite control is, therefore, likely to involve CD8(+) T-cell responses against more than one epitope. Together, these results underscore the complexity and multidimensional nature of virologic control of lentivirus infection.
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Affiliation(s)
| | - Damien C Tully
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Michael A Cruz
- Department of Pathology, University of Miami, Miami, Florida, USA
| | - Karen A Power
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | | | - David J Bean
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Colin B Ogilvie
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Rujuta Gadgil
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - Noemia S Lima
- Laboratório de Biologia Molecular de Flavivirus, Instituto Oswaldo Cruz-FIOCRUZ, Rio de Janeiro, Brazil
| | - Diogo M Magnani
- Department of Pathology, University of Miami, Miami, Florida, USA
| | - Keisuke Ejima
- Section on Statistical Genetics, Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - David B Allison
- Section on Statistical Genetics, Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Michael Piatak
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory, Frederick, Maryland, USA
| | - John D Altman
- Department of Microbiology and Immunology, Emory University, Atlanta, Georgia, USA
| | - Christopher L Parks
- International AIDS Vaccine Initiative, AIDS Vaccine Design and Development Laboratory, Brooklyn Army Terminal, Brooklyn, New York, USA
| | - Eva G Rakasz
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Saverio Capuano
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Ricardo Galler
- Instituto de Tecnologia em Imunobiológicos, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Myrna C Bonaldo
- Laboratório de Biologia Molecular de Flavivirus, Instituto Oswaldo Cruz-FIOCRUZ, Rio de Janeiro, Brazil
| | - Jeffrey D Lifson
- AIDS and Cancer Virus Program, Leidos Biomedical Research, Inc., Frederick National Laboratory, Frederick, Maryland, USA
| | - Todd M Allen
- Ragon Institute of MGH, MIT and Harvard, Cambridge, Massachusetts, USA
| | - David I Watkins
- Department of Pathology, University of Miami, Miami, Florida, USA
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The Breadth of Expandable Memory CD8+ T Cells Inversely Correlates with Residual Viral Loads in HIV Elite Controllers. J Virol 2015; 89:10735-47. [PMID: 26269189 DOI: 10.1128/jvi.01527-15] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Accepted: 07/27/2015] [Indexed: 12/28/2022] Open
Abstract
UNLABELLED Previous studies have shown that elite controllers with minimal effector T cell responses harbor a low-frequency, readily expandable, highly functional, and broadly directed memory population. Here, we interrogated the in vivo relevance of this cell population by investigating whether the breadth of expandable memory responses is associated with the magnitude of residual viremia in individuals achieving durable suppression of HIV infection. HIV-specific memory CD8(+) T cells were expanded by using autologous epitopic and variant peptides. Viral load was measured by an ultrasensitive single-copy PCR assay. Following expansion, controllers showed a greater increase in the overall breadth of Gag responses than did untreated progressors (P = 0.01) as well as treated progressors (P = 0.0003). Nef- and Env-specific memory cells expanded poorly for all groups, and their expanded breadths were indistinguishable among groups (P = 0.9 for Nef as determined by a Kruskal-Wallis test; P = 0.6 for Env as determined by a Kruskal-Wallis test). More importantly, we show that the breadth of expandable, previously undetectable Gag-specific responses was inversely correlated with residual viral load (r = -0.6; P = 0.009). Together, these data reveal a direct link between the abundance of Gag-specific expandable memory responses and prolonged maintenance of low-level viremia. Our studies highlight a CD8(+) T cell feature that would be desirable in a vaccine-induced T cell response. IMPORTANCE Many studies have shown that the rare ability of some individuals to control HIV infection in the absence of antiretroviral therapy appears to be heavily dependent upon special HIV-specific killer T lymphocytes that are able to inhibit viral replication. The identification of key features of these immune cells has the potential to inform rational HIV vaccine design. This study shows that a special subset of killer lymphocytes, known as central memory CD8(+) T lymphocytes, is at least partially involved in the durable control of HIV replication. HIV controllers maintain a large proportion of Gag-specific expandable memory CD8(+) T cells involved in ongoing viral suppression. These data suggest that induction of this cell subset by future HIV vaccines may be important for narrowing possible routes of rapid escape from vaccine-induced CD8(+) T cell responses.
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HLA-B*57 elite suppressor and chronic progressor HIV-1 isolates replicate vigorously and cause CD4+ T cell depletion in humanized BLT mice. J Virol 2014; 88:3340-52. [PMID: 24390323 DOI: 10.1128/jvi.03380-13] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Elite controllers or suppressors (ES) are HIV-1-infected patients who maintain undetectable viral loads without antiretroviral therapy. The mechanism of control remains unclear, but the HLA-B*57 allele is overrepresented in cohorts of these patients. However, many HLA-B*57 patients develop progressive disease, and some studies have suggested that infection with defective viruses may be the cause of the lack of high levels of virus replication and disease progression in ES. We therefore performed a comprehensive comparative in vivo and in vitro characterization of viruses isolated from well-defined ES. For this purpose, we first performed full-genome sequence analysis and in vitro fitness assays on replication-competent isolates from HLA-B*57 ES and HLA-B*57 chronic progressors (CPs). Under our experimental conditions, we found that isolates from ES and CPs can replicate in vitro. However, since inherently these assays involve the use of unnaturally in vitro-activated cells, we also investigated the replication competence and pathogenic potential of these HIV isolates in vivo using humanized BLT mice. The results from these analyses demonstrate that virus isolates from ES are fully replication competent in vivo and can induce peripheral and systemic CD4 T cell depletion. These results provide the first direct in vivo evidence that viral fitness does not likely determine clinical outcome in HLA-B*57 patients and that elite suppressors can control replication-competent, fully pathogenic viruses. A better understanding of the immunological bases of viral suppression in ES will serve to inform novel approaches to preventive and therapeutic HIV vaccine design. IMPORTANCE Elite suppressors are HIV-1-infected patients who have undetectable levels of viremia despite not being on antiviral drugs. One of the most fundamental questions about this phenomenon involves the mechanism of control. To address this question, we isolated virus from elite suppressors and from HIV-1-infected patients who have the usual progressive disease course. We compared how well the isolates from the two groups of patients replicated in culture and in humanized mice. Our results suggest that elite suppressors are capable of controlling HIV-1 due to the possession of unique host factors rather than infection with defective virus.
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10
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Tertiary mutations stabilize CD8+ T lymphocyte escape-associated compensatory mutations following transmission of simian immunodeficiency virus. J Virol 2013; 88:3598-604. [PMID: 24371068 DOI: 10.1128/jvi.03304-13] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Compensatory mutations offset fitness defects resulting from CD8(+) T lymphocyte (CD8(TL))-mediated escape, but their impact on viral evolution following transmission to naive hosts remains unclear. Here, we investigated the reversion kinetics of Gag(181-189)CM9 CD8(TL) escape-associated compensatory mutations in simian immunodeficiency virus (SIV)-infected macaques. Preexisting compensatory mutations did not result in acute-phase escape of the SIVmac239 CD8(TL) epitope Gag(181-189)CM9 and instead required a tertiary mutation for stabilization in the absence of Gag(181-189)CM9 escape mutations. Therefore, transmitted compensatory mutations do not necessarily predict rapid CD8(TL) escape.
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11
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Walsh AD, Bimber BN, Das A, Piaskowski SM, Rakasz EG, Bean AT, Mudd PA, Ericsen AJ, Wilson NA, Hughes AL, O'Connor DH, Maness NJ. Acute phase CD8+ T lymphocytes against alternate reading frame epitopes select for rapid viral escape during SIV infection. PLoS One 2013; 8:e61383. [PMID: 23671565 PMCID: PMC3645990 DOI: 10.1371/journal.pone.0061383] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 03/07/2013] [Indexed: 12/13/2022] Open
Abstract
CD8+ T Lymphocytes (CTL) can control AIDS virus replication. However, natural selection favoring viral variants that escape CTL recognition is a common feature of both simian immunodeficiency virus (SIV) infection of macaques and HIV infection of humans. Emerging data indicate that CTL directed against alternate reading frame (ARF)-derived epitopes (a.k.a. cryptic epitopes) are important components of the total virus-specific response in SIV and HIV infection but the contributions of these responses during the critical first several weeks of infection have not been determined. We used a focused deep sequencing approach to examine acute phase viral evolution in response to CTL targeting two polypeptides encoded by ARFs of SIVmac239 in SIV-infected rhesus macaques. We report high magnitude CTL responses as early as three weeks post-infection against epitopes within both ARFs, which both overlap the 5′ end of the env gene. Further, mutations accumulated in the epitopes by three to four weeks post infection consistent with viral escape. Interestingly, these mutations largely maintained the primary amino acid sequence of the overlapping Envelope protein. Our data show that high frequency CTL target cryptic epitopes and exert selective pressure on SIV during the acute phase, underscoring the importance of these unique immune responses.
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Affiliation(s)
- Andrew D. Walsh
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Benjamin N. Bimber
- Oregon National Primate Research Center, Oregon Health and Science University, Beaverton, Oregon, United States of America
| | - Arpita Das
- Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
| | - Shari M. Piaskowski
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Eva G. Rakasz
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Alexander T. Bean
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Philip A. Mudd
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Medical Scientist Training Program, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Adam J. Ericsen
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Nancy A. Wilson
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Austin L. Hughes
- Department of Biological Sciences, University of South Carolina, Columbia, South Carolina, United States of America
| | - David H. O'Connor
- Department of Pathology and Laboratory Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Wisconsin National Primate Research Center, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Nicholas J. Maness
- Division of Microbiology, Tulane National Primate Research Center, Covington, Louisiana, United States of America
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
- * E-mail:
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Lech PJ, Tobin GJ, Bushnell R, Gutschenritter E, Pham LD, Nace R, Verhoeyen E, Cosset FL, Muller CP, Russell SJ, Nara PL. Epitope dampening monotypic measles virus hemagglutinin glycoprotein results in resistance to cocktail of monoclonal antibodies. PLoS One 2013; 8:e52306. [PMID: 23300970 PMCID: PMC3536790 DOI: 10.1371/journal.pone.0052306] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 11/16/2012] [Indexed: 12/21/2022] Open
Abstract
The measles virus (MV) is serologically monotypic. Life-long immunity is conferred by a single attack of measles or following vaccination with the MV vaccine. This is contrary to viruses such as influenza, which readily develop resistance to the immune system and recur. A better understanding of factors that restrain MV to one serotype may allow us to predict if MV will remain monotypic in the future and influence the design of novel MV vaccines and therapeutics. MV hemagglutinin (H) glycoprotein, binds to cellular receptors and subsequently triggers the fusion (F) glycoprotein to fuse the virus into the cell. H is also the major target for neutralizing antibodies. To explore if MV remains monotypic due to a lack of plasticity of the H glycoprotein, we used the technology of Immune Dampening to generate viruses with rationally designed N-linked glycosylation sites and mutations in different epitopes and screened for viruses that escaped monoclonal antibodies (mAbs). We then combined rationally designed mutations with naturally selected mutations to generate a virus resistant to a cocktail of neutralizing mAbs targeting four different epitopes simultaneously. Two epitopes were protected by engineered N-linked glycosylations and two epitopes acquired escape mutations via two consecutive rounds of artificial selection in the presence of mAbs. Three of these epitopes were targeted by mAbs known to interfere with receptor binding. Results demonstrate that, within the epitopes analyzed, H can tolerate mutations in different residues and additional N-linked glycosylations to escape mAbs. Understanding the degree of change that H can tolerate is important as we follow its evolution in a host whose immunity is vaccine induced by genotype A strains instead of multiple genetically distinct wild-type MVs.
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Affiliation(s)
- Patrycja J Lech
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, United States of America.
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Abstract
Successful vaccine development for infectious diseases has largely been achieved in settings where natural immunity to the pathogen results in clearance in at least some individuals. HIV presents an additional challenge in that natural clearance of infection does not occur, and the correlates of immune protection are still uncertain. However, partial control of viremia and markedly different outcomes of disease are observed in HIV-infected persons. Here, we examine the antiviral mechanisms implicated by one variable that has been consistently associated with extremes of outcome, namely HLA class I alleles, and in particular HLA-B, and examine the mechanisms by which this modulation is likely to occur and the impact of these interactions on evolution of the virus and the host. Studies to date provide evidence for both HLA-dependent and epitope-dependent influences on viral control and viral evolution and have important implications for the continued quest for an effective HIV vaccine.
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