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Jurisic L, Malatesta D, Zaccaria G, Di Teodoro G, Bonfini B, Valleriani F, Teodori L, Bencivenga F, Leone A, Ripà P, D'Innocenzo V, Rossi E, Lorusso A. Immunization with Usutu virus and with a chimeric West Nile virus (WNV) harboring Usutu-E protein protects immunocompetent adult mice against lethal challenges with different WNV lineage 1 and 2 strains. Vet Microbiol 2023; 277:109636. [PMID: 36580873 DOI: 10.1016/j.vetmic.2022.109636] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 12/09/2022] [Accepted: 12/11/2022] [Indexed: 12/15/2022]
Abstract
West Nile virus (WNV) and Usutu virus (USUV), two antigenically related flaviviruses co-circulating in Europe, can cause severe neurological disease in animals and humans. The immune response against USUV and WNV and their immunopathogenesis are still poorly investigated. Here we present results upon sequential infections of adult immunocompetent CD-1 and BALB/c mice primed with two different doses (high dose, HD or low dose, LD) of an USUV isolate and challenged with HD or LD of three different WNV isolates. CD-1 and BALB/c LD USUV-primed mice, regardless of the dose, are largely protected from lethal WNV challenges despite showing no detectable neutralizing antibodies. Furthermore, mice immunized with a chimeric virus harboring the E protein of USUV within the WNV backbone (WNVE-USUV) are protected against a lethal challenge with WNV. We believe these findings could contribute to understanding the dynamics of the interaction during sequential infection of these two flaviviruses.
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Affiliation(s)
- Lucija Jurisic
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy; Faculty of Veterinary Medicine, University of Teramo, Teramo, Italy
| | - Daniela Malatesta
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Guendalina Zaccaria
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Giovanni Di Teodoro
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Barbara Bonfini
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Fabrizia Valleriani
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Liana Teodori
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | | | - Alessandra Leone
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Paola Ripà
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Vincenzo D'Innocenzo
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Emanuela Rossi
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy
| | - Alessio Lorusso
- Istituto Zooprofilattico Sperimentale Teramo (IZS-Te), Campo Boario, Teramo, Italy.
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Harris PE, Brasel T, Massey C, Herst CV, Burkholz S, Lloyd P, Blankenberg T, Bey TM, Carback R, Hodge T, Ciotlos S, Wang L, Comer JE, Rubsamen RM. A Synthetic Peptide CTL Vaccine Targeting Nucleocapsid Confers Protection from SARS-CoV-2 Challenge in Rhesus Macaques. Vaccines (Basel) 2021; 9:520. [PMID: 34070152 PMCID: PMC8158516 DOI: 10.3390/vaccines9050520] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 05/10/2021] [Accepted: 05/13/2021] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Persistent transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has given rise to a COVID-19 pandemic. Several vaccines, conceived in 2020, that evoke protective spike antibody responses are being deployed in mass public health vaccination programs. Recent data suggests, however, that as sequence variation in the spike genome accumulates, some vaccines may lose efficacy. METHODS Using a macaque model of SARS-CoV-2 infection, we tested the efficacy of a peptide-based vaccine targeting MHC class I epitopes on the SARS-CoV-2 nucleocapsid protein. We administered biodegradable microspheres with synthetic peptides and adjuvants to rhesus macaques. Unvaccinated control and vaccinated macaques were challenged with 1 × 108 TCID50 units of SARS-CoV-2, followed by assessment of clinical symptoms and viral load, chest radiographs, and sampling of peripheral blood and bronchoalveolar lavage (BAL) fluid for downstream analysis. RESULTS Vaccinated animals were free of pneumonia-like infiltrates characteristic of SARS-CoV-2 infection and presented with lower viral loads relative to controls. Gene expression in cells collected from BAL samples of vaccinated macaques revealed a unique signature associated with enhanced development of adaptive immune responses relative to control macaques. CONCLUSIONS We demonstrate that a room temperature stable peptide vaccine based on known immunogenic HLA class I bound CTL epitopes from the nucleocapsid protein can provide protection against SARS-CoV-2 infection in nonhuman primates.
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Affiliation(s)
- Paul E. Harris
- Department of Medicine, Columbia University, P&S 10-502, 650 West 168th Street, New York, NY 10032, USA;
| | - Trevor Brasel
- Department of Microbiology & Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555, USA; (T.B.); (C.M.)
| | - Christopher Massey
- Department of Microbiology & Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555, USA; (T.B.); (C.M.)
| | - C. V. Herst
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Scott Burkholz
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Peter Lloyd
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Tikoes Blankenberg
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
- Dignity Health Mercy Medical Center, Redding, CA 96001, USA;
| | - Thomas M. Bey
- Dignity Health Mercy Medical Center, Redding, CA 96001, USA;
| | - Richard Carback
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Thomas Hodge
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Serban Ciotlos
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Lu Wang
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
| | - Jason E. Comer
- Department of Microbiology & Immunology, University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555, USA; (T.B.); (C.M.)
| | - Reid M. Rubsamen
- Flow Pharma Inc., 4829 Galaxy Parkway, Suite K, Warrensville Heights, OH 44128, USA; (C.V.H.); (S.B.); (P.L.); (T.B.); (R.C.); (T.H.); (S.C.); (L.W.)
- The Department of Anesthesiology and Perioperative Medicine, Case Western Reserve School of Medicine, Cleveland Medical Center, University Hospitals, Cleveland, OH 44106, USA
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, MA 96001, USA
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3
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Grubor-Bauk B, Wijesundara DK, Masavuli M, Abbink P, Peterson RL, Prow NA, Larocca RA, Mekonnen ZA, Shrestha A, Eyre NS, Beard MR, Gummow J, Carr J, Robertson SA, Hayball JD, Barouch DH, Gowans EJ. NS1 DNA vaccination protects against Zika infection through T cell-mediated immunity in immunocompetent mice. SCIENCE ADVANCES 2019; 5:eaax2388. [PMID: 31844662 PMCID: PMC6905874 DOI: 10.1126/sciadv.aax2388] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Accepted: 10/08/2019] [Indexed: 05/08/2023]
Abstract
The causal association of Zika virus (ZIKV) with microcephaly, congenital malformations in infants, and Guillain-Barré syndrome in adults highlights the need for effective vaccines. Thus far, efforts to develop ZIKV vaccines have focused on the viral envelope. ZIKV NS1 as a vaccine immunogen has not been fully explored, although it can circumvent the risk of antibody-dependent enhancement of ZIKV infection, associated with envelope antibodies. Here, we describe a novel DNA vaccine encoding a secreted ZIKV NS1, that confers rapid protection from systemic ZIKV infection in immunocompetent mice. We identify novel NS1 T cell epitopes in vivo and show that functional NS1-specific T cell responses are critical for protection against ZIKV infection. We demonstrate that vaccine-induced anti-NS1 antibodies fail to confer protection in the absence of a functional T cell response. This highlights the importance of using NS1 as a target for T cell-based ZIKV vaccines.
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Affiliation(s)
- B. Grubor-Bauk
- Discipline of Surgery, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
- Corresponding author.
| | - D. K. Wijesundara
- Discipline of Surgery, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - M. Masavuli
- Discipline of Surgery, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - P. Abbink
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - R. L. Peterson
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - N. A. Prow
- Experimental Therapeutics Laboratory, Cancer Research Institute, School of Pharmacy and Medical Science, University of South Australia, Adelaide, SA 5000, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, QLD 4029, Australia
- Australian Infectious Diseases Research Centre, Brisbane, QLD 4072, Australia
| | - R. A. Larocca
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Z. A. Mekonnen
- Discipline of Surgery, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - A. Shrestha
- Discipline of Surgery, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
| | - N. S. Eyre
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - M. R. Beard
- Research Centre for Infectious Diseases, School of Biological Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - J. Gummow
- Gene Silencing and Expression Core Facility, Adelaide Health and Medical Sciences, Robinson Research Institute, University of Adelaide, Adelaide, SA 5005, Australia
| | - J. Carr
- Microbiology and Infectious Diseases, College of Medicine and Public Health, Flinders University, Adelaide, SA 5042, Australia
| | - S. A. Robertson
- Robinson Research Institute, School of Medicine, University of Adelaide, Adelaide, SA 5005, Australia
| | - J. D. Hayball
- Experimental Therapeutics Laboratory, Cancer Research Institute, School of Pharmacy and Medical Science, University of South Australia, Adelaide, SA 5000, Australia
- Robinson Research Institute, School of Medicine, University of Adelaide, Adelaide, SA 5005, Australia
| | - D. H. Barouch
- Center for Virology and Vaccine Research, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
- Ragon Institute of MGH, MIT, and Harvard, Cambridge, MA 02139, USA
| | - E. J. Gowans
- Discipline of Surgery, University of Adelaide and Basil Hetzel Institute for Translational Health Research, Adelaide, SA 5005, Australia
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Hassert M, Brien JD, Pinto AK. Mouse Models of Heterologous Flavivirus Immunity: A Role for Cross-Reactive T Cells. Front Immunol 2019; 10:1045. [PMID: 31143185 PMCID: PMC6520664 DOI: 10.3389/fimmu.2019.01045] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/24/2019] [Indexed: 12/20/2022] Open
Abstract
Most of the world is at risk of being infected with a flavivirus such as dengue virus, West Nile virus, yellow fever virus, Japanese encephalitis virus, tick-borne encephalitis virus, and Zika virus, significantly impacting millions of lives. Importantly, many of these genetically similar viruses co-circulate within the same geographic regions, making it likely for individuals living in areas of high flavivirus endemicity to be infected with multiple flaviviruses during their lifetime. Following a flavivirus infection, a robust virus-specific T cell response is generated and the memory recall of this response has been demonstrated to provide long-lasting immunity, protecting against reinfection with the same pathogen. However, multiple studies have shown that this flavivirus specific T cell response can be cross-reactive and active during heterologous flavivirus infection, leading to the question: How does immunity to one flavivirus shape immunity to the next, and how does this impact disease? It has been proposed that in some cases unfavorable disease outcomes may be caused by lower avidity cross-reactive memory T cells generated during a primary flavivirus infection that preferentially expand during a secondary heterologous infection and function sub optimally against the new pathogen. While in other cases, these cross-reactive cells still have the potential to facilitate cross-protection. In this review, we focus on cross-reactive T cell responses to flaviviruses and the concepts and consequences of T cell cross-reactivity, with particular emphasis linking data generated using murine models to our new understanding of disease outcomes following heterologous flavivirus infection.
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Affiliation(s)
- Mariah Hassert
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, MO, United States
| | - James D Brien
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, MO, United States
| | - Amelia K Pinto
- Department of Molecular Microbiology and Immunology, Saint Louis University, St. Louis, MO, United States
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Trobaugh DW, Sun C, Dunn MD, Reed DS, Klimstra WB. Rational design of a live-attenuated eastern equine encephalitis virus vaccine through informed mutation of virulence determinants. PLoS Pathog 2019; 15:e1007584. [PMID: 30742691 PMCID: PMC6386422 DOI: 10.1371/journal.ppat.1007584] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Revised: 02/22/2019] [Accepted: 01/15/2019] [Indexed: 12/20/2022] Open
Abstract
Live attenuated vaccines (LAVs), if sufficiently safe, provide the most potent and durable anti-pathogen responses in vaccinees with single immunizations commonly yielding lifelong immunity. Historically, viral LAVs were derived by blind passage of virulent strains in cultured cells resulting in adaptation to culture and a loss of fitness and disease-causing potential in vivo. Mutations associated with these phenomena have been identified but rarely have specific attenuation mechanisms been ascribed, thereby limiting understanding of the attenuating characteristics of the LAV strain and applicability of the attenuation mechanism to other vaccines. Furthermore, the attenuated phenotype is often associated with single nucleotide changes in the viral genome, which can easily revert to the virulent sequence during replication in animals. Here, we have used a rational approach to attenuation of eastern equine encephalitis virus (EEEV), a mosquito-transmitted alphavirus that is among the most acutely human-virulent viruses endemic to North America and has potential for use as an aerosolized bioweapon. Currently, there is no licensed antiviral therapy or vaccine for this virus. Four virulence loci in the EEEV genome were identified and were mutated individually and in combination to abrogate virulence and to resist reversion. The resultant viruses were tested for virulence in mice to examine the degree of attenuation and efficacy was tested by subcutaneous or aerosol challenge with wild type EEEV. Importantly, all viruses containing three or more mutations were avirulent after intracerebral infection of mice, indicating a very high degree of attenuation. All vaccines protected from subcutaneous EEEV challenge while a single vaccine with three mutations provided reproducible, near-complete protection against aerosol challenge. These results suggest that informed mutation of virulence determinants is a productive strategy for production of LAVs even with highly virulent viruses such as EEEV. Furthermore, these results can be directly applied to mutation of analogous virulence loci to create LAVs from other viruses. Live-attenuated vaccines (LAVs) mimic a natural virus infection and elicit high levels of neutralizing antibodies that can persist for long times. Historically, LAVs have been created by blind passaging of the virus leading to attenuating mutations in the viral genome with no known mechanism of action. We have used an informed approach to create a LAV for eastern equine encephalitis virus (EEEV). EEEV is one of the most highly virulent mosquito-borne viruses in the United States, and there is currently no approved vaccine or antiviral therapeutic. Here, we created a series of LAVs by combining mutations of four alphavirus virulence loci that have known functions. We demonstrate that viruses containing at last three mutations are highly attenuated after both a subcutaneous and intracerebral infection of mice and provide protective immunity against both a subcutaneous and aerosol challenge. We have also identified a key mutation, elimination of the miR-142-3p microRNA biding sites in the EEEV 3’ untranslated region, as critical for myeloid cell replication and essential for eliciting optimal cytokine responses, T cell responses, and protection from challenge. In summary, our results provide a rationale for an informed approach to the generation of LAVs against arboviruses.
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Affiliation(s)
- Derek W. Trobaugh
- Center for Vaccine Research, Department of Immunology, University of Pittsburgh, Pittsburgh, PA United States of America
| | - Chengqun Sun
- Center for Vaccine Research, Department of Immunology, University of Pittsburgh, Pittsburgh, PA United States of America
| | - Matthew D. Dunn
- Center for Vaccine Research, Department of Immunology, University of Pittsburgh, Pittsburgh, PA United States of America
| | - Douglas S. Reed
- Center for Vaccine Research, Department of Immunology, University of Pittsburgh, Pittsburgh, PA United States of America
| | - William B. Klimstra
- Center for Vaccine Research, Department of Immunology, University of Pittsburgh, Pittsburgh, PA United States of America
- * E-mail:
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6
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Saron WAA, Rathore APS, Ting L, Ooi EE, Low J, Abraham SN, St. John AL. Flavivirus serocomplex cross-reactive immunity is protective by activating heterologous memory CD4 T cells. SCIENCE ADVANCES 2018; 4:eaar4297. [PMID: 29978039 PMCID: PMC6031378 DOI: 10.1126/sciadv.aar4297] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Accepted: 05/22/2018] [Indexed: 05/07/2023]
Abstract
How previous immunity influences immune memory recall and protection against related flaviviruses is largely unknown, yet encounter with multiple flaviviruses in a lifetime is increasingly likely. Using sequential challenges with dengue virus (DENV), yellow fever virus (YFV), and Japanese encephalitis virus (JEV), we induced cross-reactive cellular and humoral immunity among flaviviruses from differing serocomplexes. Antibodies against JEV enhanced DENV replication; however, JEV immunity was protective in vivo during secondary DENV1 infection, promoting rapid gains in antibody avidity. Mechanistically, JEV immunity activated dendritic cells and effector memory T cells, which developed a T follicular helper cell phenotype in draining lymph nodes upon secondary DENV1 infection. We identified cross-reactive epitopes that promote recall from a pool of flavivirus serocomplex cross-reactive memory CD4 T cells and confirmed that a similar serocomplex cross-reactive immunity occurs in humans. These results show that sequential immunizations for flaviviruses sharing CD4 epitopes should promote protection during a subsequent heterologous infection.
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Affiliation(s)
- Wilfried A. A. Saron
- Program in Emerging Infectious Diseases, Duke–National University of Singapore, Singapore, Singapore
| | - Abhay P. S. Rathore
- Program in Emerging Infectious Diseases, Duke–National University of Singapore, Singapore, Singapore
- Department of Pathology, Duke University Medical Center, Durham, NC 27705, USA
| | - Lim Ting
- Program in Emerging Infectious Diseases, Duke–National University of Singapore, Singapore, Singapore
| | - Eng Eong Ooi
- Program in Emerging Infectious Diseases, Duke–National University of Singapore, Singapore, Singapore
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, Singapore, Singapore
| | - Jenny Low
- Department of Infectious Diseases, Singapore General Hospital, Singapore, Singapore
| | - Soman N. Abraham
- Program in Emerging Infectious Diseases, Duke–National University of Singapore, Singapore, Singapore
- Department of Pathology, Duke University Medical Center, Durham, NC 27705, USA
| | - Ashley L. St. John
- Program in Emerging Infectious Diseases, Duke–National University of Singapore, Singapore, Singapore
- Department of Pathology, Duke University Medical Center, Durham, NC 27705, USA
- Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore
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7
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CD8 T cells protect adult naive mice from JEV-induced morbidity via lytic function. PLoS Negl Trop Dis 2017; 11:e0005329. [PMID: 28151989 PMCID: PMC5308832 DOI: 10.1371/journal.pntd.0005329] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Revised: 02/14/2017] [Accepted: 01/13/2017] [Indexed: 12/02/2022] Open
Abstract
Following Japanese encephalitis virus (JEV) infection neutralizing antibodies are shown to provide protection in a significant proportion of cases, but not all, suggesting additional components of immune system might also contribute to elicit protective immune response. Here we have characterized the role of T cells in offering protection in adult mice infected with JEV. Mice lacking α/β–T cells (TCRβ–null) are highly susceptible and die over 10–18 day period as compared to the wild-type (WT) mice which are resistant. This is associated with high viral load, higher mRNA levels of proinflammatory cytokines and breach in the blood-brain-barrier (BBB). Infected WT mice do not show a breach in BBB; however, in contrast to TCRβ-null, they show the presence of T cells in the brain. Using adoptive transfer of cells with specific genetic deficiencies we see that neither the presence of CD4 T cells nor cytokines such as IL-4, IL-10 or interferon-gamma have any significant role in offering protection from primary infection. In contrast, we show that CD8 T cell deficiency is more critical as absence of CD8 T cells alone increases mortality in mice infected with JEV. Further, transfer of T cells from beige mice with defects in granular lytic function into TCRβ-null mice shows poor protection implicating granule-mediated target cell lysis as an essential component for survival. In addition, for the first time we report that γ/δ-T cells also make significant contribution to confer protection from JEV infection. Our data show that effector CD8 T cells play a protective role during primary infection possibly by preventing the breach in BBB and neuronal damage. Japanese encephalitis virus (JEV) commonly infects human beings in developing countries including those in Southeast Asia. While the majority of the infected people suffer from mild illness, a minority suffers from encephalitis which may lead to death. The virus is transmitted by mosquito bites and elimination of mosquitoes is not a practical answer to prevent the disease, therefore, prevention by vaccination is a desired goal. While various vaccines are clinically tried and some are marketed further improvement in vaccines is still possible. In a complex disease like JE many components of the immune system contribute to variable extent in protection. We show here that one subset of T cells called CD8 cells which are capable of killing infected cells are very critical for providing protection against JEV infection in mice. In the absence of T cells we also observed that virus reaches the brain early, unlike in the presence of T cells, and this possibly results in high virus load in the brain leading to worsening of the condition and death. Thus, our data help in identifying the role of CD8 T cells in protection from lethal JEV infection and the information may be useful for modifying and/or developing vaccine for prevention of JEV-mediated disease.
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8
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Krylova NV, Smolina TP, Leonova GN. Molecular Mechanisms of Interaction Between Human Immune Cells and Far Eastern Tick-Borne Encephalitis Virus Strains. Viral Immunol 2015; 28:272-81. [PMID: 25695407 PMCID: PMC4486442 DOI: 10.1089/vim.2014.0083] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Although studies have established that immune mechanisms are important in controlling tick-borne encephalitis virus (TBEV) infection, the interactions of different TBEV strains with cells of innate and adaptive immunity are not well understood. In this study, the ability of two Far Eastern subtype TBEV strains (Dal'negorsk and Primorye-183) with various degrees of pathogenicity for humans to modulate the expression of membrane molecules differently on human immune cells were investigated using a whole-blood flow cytometry-based assay. The whole-blood samples (from 10 healthy donors) were infected with TBEV strains and analyzed for the virus binding to the blood cells, as well as expression of adhesion (CD11b and ICAM-1) and activation (CD69, CD25, CD95) molecules on the surfaces of monocytes, granulocytes, natural killer (NK) cells, and T-lymphocytes (CD4+, CD8+) at selected times (3, 6, and 24 h post-infection). It was found that the highly pathogenic Dal'negorsk strain penetrated rapidly and was actively replicated in the blood cells, inducing downregulation of CD11b, ICAM-1, and CD69 on monocytes and a significant decrease of NK cells expressing CD69, CD25, CD95, and CD8 T-lymphocytes expressing CD69 compared with the mock-infected cells. The nonpathogenic Primorye-183 strain penetrated slowly and was replicated in the blood cells, but caused a significant increase in the adhesion and activation of molecule expression to trigger innate defense mechanisms and enable the rapid elimination of the virus from the organism. Thus, TBEV-induced activation or suppression of adhesion and activation receptors expression form an essential part of fundamental virus properties, that is, virulence and pathogenicity.
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Affiliation(s)
- Natalya V Krylova
- Laboratory of Flaviviral Infections, Institute of Epidemiology and Microbiology, Siberian Branch of Russian Academy of Medical Sciences, Vladivostok, Russian Federation
| | - Tatiana P Smolina
- Laboratory of Flaviviral Infections, Institute of Epidemiology and Microbiology, Siberian Branch of Russian Academy of Medical Sciences, Vladivostok, Russian Federation
| | - Galina N Leonova
- Laboratory of Flaviviral Infections, Institute of Epidemiology and Microbiology, Siberian Branch of Russian Academy of Medical Sciences, Vladivostok, Russian Federation
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9
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Of Mice and Men: Protective and Pathogenic Immune Responses to West Nile virus Infection. CURRENT TROPICAL MEDICINE REPORTS 2015; 2:41-48. [PMID: 26120511 DOI: 10.1007/s40475-015-0040-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
West Nile virus, a mosquito-borne flavivirus, first emerged in the Western Hemisphere in 1999. Although the majority of infections are asymptomatic, WNV causes significant morbidity and mortality in a minority of individuals who develop neuroinvasive disease, in particular the elderly and immunocompromised. Research in animal models has demonstrated interactions between WNV and the innate and adaptive immune system, some of which protect the host and others which are deleterious. Studies of disease pathogenesis in humans are less numerous, largely due to the complexities of WNV epidemiology. Human studies that have been done support the notion that innate and adaptive immune responses are delicately balanced and may help or harm the host. Further human investigations are needed to characterize beneficial responses to WNV with the goal of such research leading to therapeutics and effective vaccines in order to control this emerging viral disease.
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10
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Han YW, Choi JY, Uyangaa E, Kim SB, Kim JH, Kim BS, Kim K, Eo SK. Distinct dictation of Japanese encephalitis virus-induced neuroinflammation and lethality via triggering TLR3 and TLR4 signal pathways. PLoS Pathog 2014; 10:e1004319. [PMID: 25188232 PMCID: PMC4154777 DOI: 10.1371/journal.ppat.1004319] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2013] [Accepted: 07/09/2014] [Indexed: 12/22/2022] Open
Abstract
Japanese encephalitis (JE) is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9). Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3(-/-) and TLR4(-/-) mice, i.e. TLR3(-/-) mice were highly susceptible to JE, whereas TLR4(-/-) mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b(+)Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4(-/-) mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5), transcription factors (IRF-3, IRF-7), and IFN-dependent (PKR, Oas1, Mx) and independent ISGs (ISG49, ISG54, ISG56) by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3(-/-) myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4(+) and CD8(+) T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b(+)Ly-6C(high) monocytes) and CD4(+)Foxp3(+) Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components during JE progression could be responsible for determining disease outcome through regulating negative and positive factors.
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MESH Headings
- Animals
- Blotting, Western
- Brain/immunology
- Brain/metabolism
- Brain/virology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/virology
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/metabolism
- CD8-Positive T-Lymphocytes/virology
- Cells, Cultured
- Cytokines/genetics
- Cytokines/metabolism
- Encephalitis Virus, Japanese/pathogenicity
- Encephalitis, Japanese/complications
- Encephalitis, Japanese/virology
- Enzyme-Linked Immunosorbent Assay
- Immunity, Innate
- Inflammation/etiology
- Inflammation/metabolism
- Inflammation/pathology
- Macrophages/immunology
- Macrophages/metabolism
- Macrophages/virology
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Knockout
- Monocytes/immunology
- Monocytes/metabolism
- Monocytes/virology
- Myeloid Cells/immunology
- Myeloid Cells/metabolism
- Myeloid Cells/virology
- RNA, Messenger/genetics
- Real-Time Polymerase Chain Reaction
- Reverse Transcriptase Polymerase Chain Reaction
- Signal Transduction
- Toll-Like Receptor 3/physiology
- Toll-Like Receptor 4/physiology
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Affiliation(s)
- Young Woo Han
- College of Veterinary Medicine and Bio-Safety Research Institute, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
| | - Jin Young Choi
- College of Veterinary Medicine and Bio-Safety Research Institute, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
| | - Erdenebelig Uyangaa
- College of Veterinary Medicine and Bio-Safety Research Institute, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
| | - Seong Bum Kim
- College of Veterinary Medicine and Bio-Safety Research Institute, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
| | - Jin Hyoung Kim
- Department of Biology, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
| | - Bum Seok Kim
- College of Veterinary Medicine and Bio-Safety Research Institute, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
| | - Koanhoi Kim
- Department of Pharmacology, School of Medicine, Pusan National University, Yangsan, Republic of Korea
| | - Seong Kug Eo
- College of Veterinary Medicine and Bio-Safety Research Institute, College of Natural Science, Chonbuk National University, Jeonju, Republic of Korea
- * E-mail:
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11
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Choi YS, Lee DH, Shin EC. Relationship between Poor Immunogenicity of HLA-A2-Restricted Peptide Epitopes and Paucity of Naïve CD8(+) T-Cell Precursors in HLA-A2-Transgenic Mice. Immune Netw 2014; 14:219-25. [PMID: 25177254 PMCID: PMC4148492 DOI: 10.4110/in.2014.14.4.219] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2014] [Revised: 07/26/2014] [Accepted: 08/01/2014] [Indexed: 12/26/2022] Open
Abstract
We examined the immunogenicity of H-2 class I-restricted and HLA-A2-restricted epitopes through peptide immunization of HLA-A2-transgenic mice that also express mouse H-2 class I molecules. All four of the tested epitopes restricted by H-2 class I robustly elicited T-cell responses, but four of seven epitopes restricted by HLA-A2 did not induce T-cell responses, showing that HLA-A2-restricted peptide epitopes tend to be poorly immunogenic in HLA-A2-transgenic mice. This finding was confirmed in HLA-A2-transgenic mice infected with a recombinant vaccinia virus expressing hepatitis C virus proteins. We examined the precursor frequency of epitope-specific naïve CD8(+) T cells in HLA-A2-transgenic and conventional C57BL/6 mice and found that the poor immunogenicity of HLA-A2-restricted peptide epitopes is related to the paucity of naïve CD8(+) T-cell precursors in HLA-A2-transgenic mice. These results provide direction for the improvement of mouse models to study epitope repertoires and the immunodominance of human T-cell responses.
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Affiliation(s)
- Yoon Seok Choi
- Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Korea. ; Department of Internal Medicine, Chungnam National University College of Medicine, Daejeon 301-721, Korea
| | - Dong Ho Lee
- Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Korea
| | - Eui-Cheol Shin
- Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Korea
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12
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Highly pathological influenza A virus infection is associated with augmented expression of PD-1 by functionally compromised virus-specific CD8+ T cells. J Virol 2013; 88:1636-51. [PMID: 24257598 DOI: 10.1128/jvi.02851-13] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
One question that continues to challenge influenza A research is why some strains of virus are so devastating compared to their more mild counterparts. We approached this question from an immunological perspective, investigating the CD8(+) T cell response in a mouse model system comparing high- and low-pathological influenza virus infections. Our findings reveal that the early (day 0 to 5) viral titer was not the determining factor in the outcome of disease. Instead, increased numbers of antigen-specific CD8(+) T cells and elevated effector function on a per-cell basis were found in the low-pathological infection and correlated with reduced illness and later-time-point (day 6 to 10) viral titer. High-pathological infection was associated with increased PD-1 expression on influenza virus-specific CD8(+) T cells, and blockade of PD-L1 in vivo led to reduced virus titers and increased CD8(+) T cell numbers in high- but not low-pathological infection, though T cell functionality was not restored. These data show that high-pathological acute influenza virus infection is associated with a dysregulated CD8(+) T cell response, which is likely caused by the more highly inflamed airway microenvironment during the early days of infection. Therapeutic approaches specifically aimed at modulating innate airway inflammation may therefore promote efficient CD8(+) T cell activity. We show that during a severe influenza virus infection, one type of immune cell, the CD8 T cell, is less abundant and less functional than in a more mild infection. This dysregulated T cell phenotype correlates with a lower rate of virus clearance in the severe infection and is partially regulated by the expression of a suppressive coreceptor called PD-1. Treatment with an antibody that blocks PD-1 improves T cell functionality and increases virus clearance.
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13
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You S, Choi YS, Hong S, Shin EC. Priming of autoreactive CD8(+) T cells is inhibited by immunogenic peptides which are competitive for major histocompatibility complex class I binding. Immune Netw 2013; 13:86-93. [PMID: 23885222 PMCID: PMC3718923 DOI: 10.4110/in.2013.13.3.86] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 04/30/2013] [Accepted: 05/03/2013] [Indexed: 01/03/2023] Open
Abstract
In the present study, we investigated if priming of autoreactive CD8+ T cells would be inhibited by competitive peptides for major histocompatibility complex (MHC) class I binding. We used a mouse model of vitiligo which is induced by immunization of Kb-binding tyrosinase-related protein 2 (TRP2)-180 peptide. Competitive peptides for Kb binding inhibited IFN-γ production and proliferation of TRP2-180-specific CD8+ T cells upon ex vivo peptide restimulation, while other MHC class I-binding peptides did not. In mice, the capability of inhibition was influenced by T-cell immunogenicity of the competitive peptides. The competitive peptide with a high T-cell immunogenicity efficiently inhibited priming of TRP2-180-specific CD8+ T cells in vivo, whereas the competitive peptide with a low T-cell immunogenicity did not. Taken together, the inhibition of priming of autoreactive CD8+ T cells depends on not only competition of peptides for MHC class I binding but also competitive peptide-specific CD8+ T cells, suggesting that clonal expansion of autoreactive T cells would be affected by expansion of competitive peptide-specific T cells. This result provides new insights into the development of competitive peptides-based therapy for the treatment of autoimmune diseases.
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Affiliation(s)
- Sooseong You
- Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Korea
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14
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Spero D, Levitz L, De Groot AS. Report from the field: Overview of the Sixth Annual Vaccine Renaissance Conference. Hum Vaccin Immunother 2013; 9:1555-7. [PMID: 23732897 DOI: 10.4161/hv.24833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The Sixth Annual Vaccine Renaissance Conference, hosted by the Institute for Immunology and Informatics (iCubed) at the University of Rhode Island (URI), took place on October 15-17, 2012. This conference provides a forum for the review of current progress in the discovery and development of vaccines, and creates an environment for the exchange of ideas. Dr. Joel McCleary opened the conference with a warning about the importance of preparing for well-defined biowarfare threats, including tularemia and Staphylococcal enterotoxin B. Following the keynote address, sessions explored biodefense and preparation for pandemic and biowarfare threats; vaccines for emerging and re-emerging neglected tropical diseases; animal vaccines and human health; and vaccine vectors and the human microbiome. In this issue of Human Vaccines and Immunotherapeutics, seven Vaccine Renaissance Conference speakers will showcase their work; here, we describe a few of the conference highlights.
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Affiliation(s)
- Denice Spero
- Institute for Immunology and Informatics; University of Rhode Island; Providence, RI USA
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15
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Kitaura K, Fujii Y, Hayasaka D, Matsutani T, Shirai K, Nagata N, Lim CK, Suzuki S, Takasaki T, Suzuki R, Kurane I. High clonality of virus-specific T lymphocytes defined by TCR usage in the brains of mice infected with West Nile virus. THE JOURNAL OF IMMUNOLOGY 2011; 187:3919-30. [PMID: 21908734 DOI: 10.4049/jimmunol.1100442] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
It has been reported that brain-infiltrating T lymphocytes play critical roles in the clearance of West Nile virus (WNV) from the brains of mice. We characterized brain-infiltrating T lymphocytes by analyzing the TCR α- and β-chain repertoires, T cell clonality, and CDR3 sequences. CD3(+)CD8(+) T cells were localized in the WNV-infected brains. The expression of CD3, CD8, CD25, CD69, perforin, and granzymes positively correlated with viral RNA levels, and high levels of expression of IFN-γ, TNF-α, and IL-2 were detected in the brains, suggesting that Th1-like cytotoxic CD8(+) T cells are expanded in the brains in response to WNV infection. The brain-infiltrating T lymphocytes dominantly used TCR genes, VA1-1, VA2-1, VB5-2, and VB8-2, and exhibited a highly oligoclonal TCR repertoire. Interestingly, the brain-infiltrating T lymphocytes had different patterns of TCR repertoire usages among WNV-, Japanese encephalitis virus-, and tick-borne encephalitis virus-infected mice. Moreover, CD8(+) T cells isolated from the brains of WNV-infected mice produced IFN-γ and TNF-α after in vitro stimulation with peritoneal cells infected with WNV, but not with Japanese encephalitis virus. The results suggest that the infiltrating CD8(+) T cells were WNV-specific, but not cross-reactive among flaviviruses. T cells from the WNV-infected brains exhibited identical or similar CDR3 sequences in TCRα among tested mice, but somewhat diverse sequences in TCRβ. The results indicate that WNV-specific CD3(+)CD8(+) T cells expanding in the infected brains are highly oligoclonal, and they suggest that TCR α-chains play a dominant and critical role in Ag specificity of WNV-specific T cells.
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Affiliation(s)
- Kazutaka Kitaura
- Department of Rheumatology and Clinical Immunology, Clinical Research Center for Allergy and Rheumatology, Sagamihara National Hospital, National Hospital Organization, Kanagawa 228-0815, Japan
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16
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Abstract
AbstractT cell–mediated heterologous immunity to different pathogens is promising for the development of immunotherapeutic strategies. Aspergillus fumigatus and Candida albicans, the 2 most common fungal pathogens causing severe infections in immunocompromised patients, are controlled by CD4+ type 1 helper T (TH1) cells in humans and mice, making induction of fungus-specific CD4+ TH1 immunity an appealing strategy for antifungal therapy. We identified an immunogenic epitope of the A fumigatus cell wall glucanase Crf1 that can be presented by 3 common major histocompatibility complex class II alleles and that induces memory CD4+ TH1 cells with a diverse T-cell receptor repertoire that is cross-reactive to C albicans. In BALB/c mice, the Crf1 protein also elicits cross-protection against lethal infection with C albicans that is mediated by the same epitope as in humans. These data illustrate the existence of T cell–based cross-protection for the 2 distantly related clinically relevant fungal pathogens that may foster the development of immunotherapeutic strategies.
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17
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Pivotal role of antibody and subsidiary contribution of CD8+ T cells to recovery from infection in a murine model of Japanese encephalitis. J Virol 2011; 85:5446-55. [PMID: 21450826 DOI: 10.1128/jvi.02611-10] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The immunological correlates for recovery from primary Japanese encephalitis virus (JEV) infection in humans and experimental animals remain poorly defined. To investigate the relative importance of the adaptive immune responses, we have established a mouse model for Japanese encephalitis in which a low-dose virus inoculum was administered into the footpads of adult C57BL/6 mice. In this model, ~60% of the mice developed a fatal encephalitis and a virus burden in the central nervous system (CNS). Using mice lacking B cells (μMT(-/-) mice) and immune B cell transfer to wild-type mice, we show a critically important role for humoral immunity in preventing virus spread to the CNS. T cell help played an essential part in the maintenance of an effective antibody response necessary to combat the infection, since mice lacking major histocompatibility complex class II showed truncated IgM and blunted IgG responses and uniformly high lethality. JEV infection resulted in extensive CD8(+) T cell activation, judged by upregulation of surface markers CD69 and CD25 and cytokine production after stimulation with a JEV NS4B protein-derived H-2D(b)-binding peptide and trafficking of virus-immune CD8(+) T cells into the CNS. However, no significant effect of CD8(+) T cells on the survival phenotype was found, which was corroborated in knockout mice lacking key effector molecules (Fas receptor, perforin, or granzymes) of cytolytic pathways triggered by T lymphocytes. Accordingly, CD8(+) T cells are mostly dispensable for recovery from infection with JEV. This finding highlights the conflicting role that CD8(+) T cells play in the pathogenesis of JEV and closely related encephalitic flaviviruses such as West Nile virus.
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