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Rubbenstroth D. Avian Bornavirus Research—A Comprehensive Review. Viruses 2022; 14:v14071513. [PMID: 35891493 PMCID: PMC9321243 DOI: 10.3390/v14071513] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/30/2022] [Accepted: 07/05/2022] [Indexed: 02/01/2023] Open
Abstract
Avian bornaviruses constitute a genetically diverse group of at least 15 viruses belonging to the genus Orthobornavirus within the family Bornaviridae. After the discovery of the first avian bornaviruses in diseased psittacines in 2008, further viruses have been detected in passerines and aquatic birds. Parrot bornaviruses (PaBVs) possess the highest veterinary relevance amongst the avian bornaviruses as the causative agents of proventricular dilatation disease (PDD). PDD is a chronic and often fatal disease that may engulf a broad range of clinical presentations, typically including neurologic signs as well as impaired gastrointestinal motility, leading to proventricular dilatation. It occurs worldwide in captive psittacine populations and threatens private bird collections, zoological gardens and rehabilitation projects of endangered species. In contrast, only little is known about the pathogenic roles of passerine and waterbird bornaviruses. This comprehensive review summarizes the current knowledge on avian bornavirus infections, including their taxonomy, pathogenesis of associated diseases, epidemiology, diagnostic strategies and recent developments on prophylactic and therapeutic countermeasures.
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Affiliation(s)
- Dennis Rubbenstroth
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, 17493 Greifswald, Insel Riems, Germany
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Komatsu Y, Tomonaga K. Reverse genetics approaches of Borna disease virus: applications in development of viral vectors and preventive vaccines. Curr Opin Virol 2020; 44:42-48. [PMID: 32659515 DOI: 10.1016/j.coviro.2020.05.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/27/2020] [Accepted: 05/29/2020] [Indexed: 01/10/2023]
Abstract
The plasmid-based reverse genetics system, which involves generation of recombinant viruses from cloned cDNA, has accelerated the understanding of clinical and virological aspects of different viruses. Borna disease virus (BoDV) is a nonsegmented, negative-strand RNA virus that causes persistent intranuclear infection in various vertebrate species. Since its first report, reverse genetics approaches with modified strategies have greatly improved rescue efficiency of recombinant BoDV and enhanced the understanding of function of each viral protein and mechanism of intranuclear persistency. Here, we summarize different reverse genetics approaches of BoDV and recent developments in the use of reverse genetics for generation of viral vectors for gene therapy and virus-like particles for potential preventive vaccines.
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Affiliation(s)
- Yumiko Komatsu
- Laboratory of RNA Viruses, Department of Virus Research, Institute for Frontier Life and Medical Sciences (inFront), Kyoto University, Kyoto, Japan; Keihanshin Consortium for Fostering the Next Generation of Global Leaders in Research, Kyoto University, Kyoto, Japan
| | - Keizo Tomonaga
- Laboratory of RNA Viruses, Department of Virus Research, Institute for Frontier Life and Medical Sciences (inFront), Kyoto University, Kyoto, Japan; Department of Mammalian Regulatory Network, Graduate School of Biostudies, Kyoto University, Kyoto, Japan; Department of Molecular Virology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
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Rubbenstroth D, Schmidt V, Rinder M, Legler M, Corman VM, Staeheli P. Discovery of a new avian bornavirus genotype in estrildid finches (Estrildidae) in Germany. Vet Microbiol 2013; 168:318-23. [PMID: 24389254 DOI: 10.1016/j.vetmic.2013.11.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 11/27/2013] [Accepted: 11/29/2013] [Indexed: 11/18/2022]
Abstract
Avian bornaviruses (ABV) are known to be the causative agent of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). A broad range of ABV genotypes has been detected not only in psittacine birds, but also in other avian species including canary birds (Serinus canaria forma domestica) and Bengalese finches (Lonchura striata f. dom.), which are both members of the order songbirds (Passeriformes). During this study 286 samples collected from captive and wild birds of various passerine species in different parts of Germany were screened for the presence of ABV. Interestingly, only three ABV-positive samples were identified by RT-PCR. They originated from one yellow-winged pytilia (Pytilia hypogrammica) and two black-rumped waxbills (Estrilda troglodytes) from a flock of captive estrildid finches in Saxony. The ABV isolates detected here were only distantly related to ABV isolates found in passerine species in Germany and Japan and form a new genotype tentatively called ABV-EF (for "estrildid finches").
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Affiliation(s)
- Dennis Rubbenstroth
- Institute of Virology, University of Freiburg, Hermann-Herder-Straße 11, D-79104 Freiburg, Germany.
| | - Volker Schmidt
- Clinic for Birds and Reptiles, University of Leipzig, An den Tierkliniken 17, D-04103 Leipzig, Germany
| | - Monika Rinder
- Clinic for Birds, Reptiles, Amphibians and Ornamental Fish, Centre for Clinical Veterinary Medicine, University Ludwig Maximilian Munich, Sonnenstraße 18, D-85764 Oberschleißheim, Germany
| | - Marko Legler
- Clinic for Pets, Reptiles and Birds, University of Veterinary Medicine Hannover, Bünteweg 9, D-30559 Hannover, Germany
| | - Victor Max Corman
- Institute for Virology, University of Bonn, Sigmund-Freud-Straße 25, D-53127 Bonn, Germany
| | - Peter Staeheli
- Institute of Virology, University of Freiburg, Hermann-Herder-Straße 11, D-79104 Freiburg, Germany
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Avian bornaviruses are widely distributed in canary birds (Serinus canaria f. domestica). Vet Microbiol 2013; 165:287-95. [PMID: 23631925 DOI: 10.1016/j.vetmic.2013.03.024] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 03/23/2013] [Accepted: 03/28/2013] [Indexed: 11/23/2022]
Abstract
Avian bornavirus (ABV) was identified in 2008 as the causative agent of proventricular dilatation disease (PDD) in psittacine birds. In addition, ABV variants were detected in wild waterfowl and in a canary bird. PDD-like diseases were also reported in various other avian species, but it remains unknown whether ABV is involved. In this study we detected ABV in 12 of 30 tested canary bird flocks (40%), indicating a wide distribution of ABV in captive canary birds in Germany. Sequence analysis identified several distinct ABV genotypes which differ markedly from the genotypes present in psittacine birds. Some canaries naturally infected with ABV exhibited gastrointestinal and neurological symptoms which resembled PDD in psittacines, while others did not show signs of disease. Canaries experimentally inoculated with ABV developed infections of the brain and various other organs. The experimentally infected canaries transmitted the virus to sentinel birds kept in the same aviary, but did not show any clinical signs during a five month observation period. Embryonated eggs originating from ABV-infected hens contained ABV-specific RNA, but virus could not be re-isolated from embryonic tissue. These results indicate that ABV is widely distributed in canary birds and due to its association to clinical signs should be considered as a potential pathogen of this species.
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Herbein G, Varin A. The macrophage in HIV-1 infection: from activation to deactivation? Retrovirology 2010; 7:33. [PMID: 20380696 PMCID: PMC2859752 DOI: 10.1186/1742-4690-7-33] [Citation(s) in RCA: 135] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2009] [Accepted: 04/09/2010] [Indexed: 01/09/2023] Open
Abstract
Macrophages play a crucial role in innate and adaptative immunity in response to microorganisms and are an important cellular target during HIV-1 infection. Recently, the heterogeneity of the macrophage population has been highlighted. Classically activated or type 1 macrophages (M1) induced in particular by IFN-γ display a pro-inflammatory profile. The alternatively activated or type 2 macrophages (M2) induced by Th-2 cytokines, such as IL-4 and IL-13 express anti-inflammatory and tissue repair properties. Finally IL-10 has been described as the prototypic cytokine involved in the deactivation of macrophages (dM). Since the capacity of macrophages to support productive HIV-1 infection is known to be modulated by cytokines, this review shows how modulation of macrophage activation by cytokines impacts the capacity to support productive HIV-1 infection. Based on the activation status of macrophages we propose a model starting with M1 classically activated macrophages with accelerated formation of viral reservoirs in a context of Th1 and proinflammatory cytokines. Then IL-4/IL-13 alternatively activated M2 macrophages will enter into the game that will stop the expansion of the HIV-1 reservoir. Finally IL-10 deactivation of macrophages will lead to immune failure observed at the very late stages of the HIV-1 disease.
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Affiliation(s)
- Georges Herbein
- Department of Virology, UPRES EA 4266 Pathogens and Inflammation, IFR 133 INSERM, Franche-Comte University, CHU Besançon, Besançon, France.
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Richter K, Hausmann J, Staeheli P. Interferon-gamma prevents death of bystander neurons during CD8 T cell responses in the brain. THE AMERICAN JOURNAL OF PATHOLOGY 2009; 174:1799-807. [PMID: 19359516 DOI: 10.2353/ajpath.2009.080897] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
T cells restricted to neurotropic viruses are potentially harmful as their activity may result in the destruction of neurons. In the Borna disease virus (BDV) model, antiviral CD8 T cells entering the brain of infected mice cause neurological disease but no substantial loss of neurons unless the animals lack interferon-gamma (IFN-gamma). We show here that glutamate receptor antagonists failed to prevent BDV-induced neuronal loss in IFN-gamma-deficient mice, suggesting that excitotoxicity resulting from glutamate receptor overstimulation is an unlikely explanation for the neuronal damage. Experiments with IFN-gamma-deficient mice lacking eosinophils indicated that these cells, which specifically accumulate in the infected brains of IFN-gamma-deficient mice, are not responsible for CA1 neuronal death. Interestingly, BDV-induced damage of CA1 neurons was reduced significantly in IFN-gamma-deficient mice lacking perforin, suggesting a key role for CD8 T cells in this pathological process. Specific death of hippocampal CA1 neurons could be triggered by adoptive transfer of BDV-specific CD8 T cells from IFN-gamma-deficient mice into uninfected mice that express transgene-encoded BDV antigen at high level in astrocytes. These results indicate that attack by CD8 T cells that cause the death of CA1 neurons might be directed toward regional astrocytes and that IFN-gamma protects vulnerable CA1 neurons from collateral damage resulting from exposure to potentially toxic substances generated as a result of CD8 T cell-mediated impairment of astrocyte function.
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Affiliation(s)
- Kirsten Richter
- Department of Virology, University of Freiburg, Freiburg, Germany
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Protein X of Borna disease virus inhibits apoptosis and promotes viral persistence in the central nervous systems of newborn-infected rats. J Virol 2009; 83:4297-307. [PMID: 19211764 DOI: 10.1128/jvi.02321-08] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Borna disease virus (BDV) is a neurotropic member of the order Mononegavirales with noncytolytic replication and obligatory persistence in cultured cells and animals. Here we show that the accessory protein X of BDV represents the first mitochondrion-localized protein of an RNA virus that inhibits rather than promotes apoptosis induction. Rat C6 astroglioma cells persistently infected with wild-type BDV were significantly more resistant to death receptor-dependent and -independent apoptotic stimuli than uninfected cells or cells infected with a BDV mutant expressing reduced amounts of X. Confocal microscopy demonstrated that X colocalizes with mitochondria and expression of X from plasmid DNA rendered human 293T and mouse L929 cells resistant to apoptosis induction. A recombinant virus encoding a mutant X protein unable to associate with mitochondria (BDV-X(A6A7)) failed to block apoptosis in C6 cells. Furthermore, Lewis rats neonatally infected with BDV-X(A6A7) developed severe neurological symptoms and died around day 30 postinfection, whereas all animals infected with wild-type BDV remained healthy and became persistently infected. TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling) staining revealed a significant increase in the number of apoptotic cells in the brain of BDV-X(A6A7)-infected animals, whereas the numbers of CD3(+) T lymphocytes were comparable to those detected in animals infected with wild-type BDV. Our data thus indicate that inhibition of apoptosis by X promotes noncytolytic viral persistence and is required for the survival of cells in the central nervous system of BDV-infected animals.
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Polymerase read-through at the first transcription termination site contributes to regulation of borna disease virus gene expression. J Virol 2008; 82:9537-45. [PMID: 18653450 DOI: 10.1128/jvi.00639-08] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An unusually long noncoding sequence is located between the N gene of Borna disease virus (BDV) and the genes for regulatory factor X and polymerase cofactor P. Most of these nucleotides are transcribed and seem to control translation of the bicistronic X/P mRNA. We report here that Vero cells persistently infected with mutant viruses containing minor alterations in this control region showed almost normal levels of N, X, and P proteins but exhibited greatly reduced levels of mRNAs coding for these viral gene products. Surprisingly, cells infected with these BDV mutants accumulated a viral transcript 1.9 kb in length that represents a capped and polyadenylated mRNA containing the coding regions of the N, X, and P genes. Cells infected with wild-type BDV also contained substantial amounts of this read-through mRNA, which yielded both N and P protein when translated in vitro. Viruses carrying mutations that promoted read-through transcription at the first gene junction failed to replicate in the brain of adult rats. In the brains of newborn rats, these mutant viruses were able to replicate after acquiring second-site mutations in or near the termination signal located downstream of the N gene. Thus, sequence elements adjacent to the core termination signal seem to regulate the frequency by which the polymerase terminates transcription after the N gene. We conclude from these observations that BDV uses read-through transcription for fine-tuning the expression of the N, X, and P genes which, in turn, influence viral polymerase activity.
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Antiviral CD8 T cells recognize borna disease virus antigen transgenically expressed in either neurons or astrocytes. J Virol 2008; 82:3099-108. [PMID: 18184705 DOI: 10.1128/jvi.02479-07] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Borna disease virus (BDV) can persistently infect the central nervous system (CNS) of mice. The infection remains nonsymptomatic as long as antiviral CD8 T cells do not infiltrate the infected brain. BDV mainly infects neurons which reportedly carry few, if any, major histocompatibility complex class I molecules on the surface. Therefore, it remains unclear whether T cells can recognize replicating virus in these cells or whether cross-presentation of viral antigen by other cell types is important for immune recognition of BDV. To distinguish between these possibilities, we used two lines of transgenic mice that strongly express the N protein of BDV in either neurons (Neuro-N) or astrocytes (Astro-N). Since these animals are tolerant to the neo-self-antigen, we adoptively transferred T cells with specificity for BDV N. In nontransgenic mice persistently infected with BDV, the transferred cells accumulated in the brain parenchyma along with immune cells of host origin and efficiently induced neurological disease. Neurological disease was also observed if antiviral T cells were injected into the brains of Astro-N or Neuro-N but not nontransgenic control mice. Our results demonstrate that CD8 T cells can recognize foreign antigen on neurons and astrocytes even in the absence of infection or inflammation, indicating that these CNS cell types are playing an active role in immune recognition of viruses.
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Richter K, Baur K, Ackermann A, Schneider U, Hausmann J, Staeheli P. Pathogenic potential of borna disease virus lacking the immunodominant CD8 T-cell epitope. J Virol 2007; 81:11187-94. [PMID: 17686872 PMCID: PMC2045572 DOI: 10.1128/jvi.00742-07] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Borna disease virus (BDV) is a highly neurotropic, noncytolytic virus. Experimentally infected B10.BR mice remain healthy unless specific antiviral T cells that infiltrate the infected brain are triggered by immunization. In contrast, infected MRL mice spontaneously mount an antiviral T-cell response that can result in meningoencephalitis and neurological disease. The antiviral T cells may, alternatively, eliminate the virus without inducing disease if they are present in sufficient numbers before the virus replicates to high titers. Since the immune response of H-2(k) mice is directed mainly against the epitope TELEISSI located in the viral nucleoprotein N, we generated BDV mutants that feature TQLEISSI in place of TELEISSI. We show that adoptive transfer of BDV N-specific CD8 T cells induced neurological disease in B10.BR mice persistently infected with wild-type BDV but not with the mutant virus expressing TQLEISSI. Surprisingly, the mutant virus replicated less well in adult MRL wild-type mice than in mutant mice lacking mature CD8 T cells. Furthermore, when MRL mice were infected with the TQLEISSI-expressing BDV mutant as newborns, neurological disease was observed, although at a lower rate and with slower kinetics than in mice infected with wild-type virus. These results confirm that TELEISSI is the major CD8 T-cell epitope in H-2(k) mice and suggest that unidentified minor epitopes are present in the BDV proteome which are recognized rather efficiently by antiviral T cells if the dominant epitope is absent.
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Affiliation(s)
- Kirsten Richter
- Department of Virology, University of Freiburg, Hermann-Herder-Strasse 11, D-79104 Freiburg, Germany
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Ohtaki N, Kamitani W, Watanabe Y, Hayashi Y, Yanai H, Ikuta K, Tomonaga K. Downregulation of an astrocyte-derived inflammatory protein, S100B, reduces vascular inflammatory responses in brains persistently infected with Borna disease virus. J Virol 2007; 81:5940-8. [PMID: 17376896 PMCID: PMC1900267 DOI: 10.1128/jvi.02137-06] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Borna disease virus (BDV) is a neurotropic virus that causes a persistent infection in the central nervous system (CNS) of many vertebrate species. Although a severe reactive gliosis is observed in experimentally BDV-infected rat brains, little is known about the glial reactions contributing to the viral persistence and immune modulation in the CNS. In this regard, we examined the expression of an astrocyte-derived factor, S100B, in the brains of Lewis rats persistently infected with BDV. S100B is a Ca(2+)-binding protein produced mainly by astrocytes. A prominent role of this protein appears to be the promotion of vascular inflammatory responses through interaction with the receptor for advanced glycation end products (RAGE). Here we show that the expression of S100B is significantly reduced in BDV-infected brains despite severe astrocytosis with increased glial fibrillary acidic protein immunoreactivity. Interestingly, no upregulation of the expression of S100B, or RAGE, was observed in the persistently infected brains even when incited with several inflammatory stimuli, including lipopolysaccharide. In addition, expression of the vascular cell adhesion molecule 1 (VCAM-1), as well as the infiltration of encephalitogenic T cells, was significantly reduced in persistently infected brains in which an experimental autoimmune encephalomyelitis was induced by immunization with myelin-basic protein. Furthermore, we demonstrated that the continuous activation of S100B in the brain may be necessary for the progression of vascular immune responses in neonatally infected rat brains. Our results suggested that BDV infection may impair astrocyte functions via a downregulation of S100B expression, leading to the maintenance of a persistent infection.
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Affiliation(s)
- Naohiro Ohtaki
- Department of Virology, Research Institute for Microbial Diseases, Osaka University, 3-1 Yamadaoka, Suita, Osaka 565-0871, Japan
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Stahl T, Reimers C, Johne R, Schliebs R, Seeger J. Viral-induced inflammation is accompanied by beta-amyloid plaque reduction in brains of amyloid precursor protein transgenic Tg2576 mice. Eur J Neurosci 2006; 24:1923-34. [PMID: 17067295 DOI: 10.1111/j.1460-9568.2006.05069.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Amyloid plaques, one of the neuropathological hallmarks of Alzheimer's disease, and their main constituent, the amyloid beta-peptide (Abeta), are triggers of the activation of innate inflammatory mechanisms involving the activation of microglia. To dissect the effects of a non-Abeta-specific microglial activation on the Abeta metabolism, we employed a viral infection-based model. Transgenic mice expressing a mutated form of the human amyloid precursor protein (Tg2576) were used. In preceding experiments, 2-week-old transgenic mice and non-transgenic littermates were infected intracerebrally with the neurotropic Borna disease virus and investigated at 2, 4 and 14 weeks post-infection. The Borna disease virus-inoculated mice showed a persisting, subclinical infection of cortical and limbic brain areas characterized by slight T-cell infiltrates, expression of cytokines and a massive microglial activation in the hippocampus and neocortex. Viral-induced effects reached their peak at 4 weeks post-infection. In 14-month-old Tg2576 mice, characterized by the deposition of diffuse and dense-core amyloid plaques in cortical brain regions, Borna disease virus-induced microglial activation in the vicinity of Abeta deposits was used to investigate the influence of a local inflammatory response on these deposits. At 4 weeks post-infection, histometric analyses employing Abeta immunohistochemistry revealed a decrease of the cortical and hippocampal Abeta-immunopositive area. This overall decrease was accompanied by a decrease of parenchymal thioflavin-S-positive amyloid deposits and an increase of such deposits in the walls of cerebral vessels, which indicates that the elicitation of a non-Abeta-specific microglial activation may contribute to a reduction of Abeta in the brain parenchyma.
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Affiliation(s)
- Tobias Stahl
- Department of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, University of Leipzig, An den Tierkliniken 43, D-04109 Leipzig, Germany.
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Abstract
Human immunodeficiency virus-1 (HIV-1) neuroinvasion occurs early (during period of initial viremia), leading to infection of a limited amount of susceptible cells with low CD4 expression. Protective cellular and humoral immunity eliminate and suppress viral replication relatively quickly due to peripheral immune responses and the low level of initial central nervous system (CNS) infection. Upregulation of the brain protective mechanisms against lymphocyte entry and survival (related to immune privilege) helps reduce viral load in the brain. The local immune compartment dictates local viral evolution as well as selection of cytotoxic lymphocytes and immunoglobulin G specificity. Such status can be sustained until peripheral immune anti-viral responses fail. Activation of microglia and astrocytes, due to local or peripheral triggers, increases chemokine production, enhances traffic of infected cells into the CNS, upregulates viral replication in resident brain macrophages, and significantly augments the spread of viral species. The combination of these factors leads to the development of HIV-1 encephalitis-associated neurocognitive decline and patient death. Understanding the immune-privileged state created by virus, the brain microenvironment, and the ability to enhance anti-viral immunity offer new therapeutic strategies for treatment of HIV-1 CNS infection.
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Affiliation(s)
- Yuri Persidsky
- Center for Neurovirology and Neurodegenerative Disorders, University of Nebraska Medical Center, Omaha, NE 68198-5215, USA.
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Awasthi S, Awasthi V, Magee DM, Coalson JJ. Efficacy of antigen 2/proline-rich antigen cDNA-transfected dendritic cells in immunization of mice against Coccidioides posadasii. THE JOURNAL OF IMMUNOLOGY 2005; 175:3900-6. [PMID: 16148136 DOI: 10.4049/jimmunol.175.6.3900] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Coccidioides posadasii causes coccidioidomycosis, or Valley fever, in the endemic regions of the Southwestern United States. The susceptibility to C. posadasii infection has been attributed to a decreased Th1 cellular response. APCs, especially dendritic cells (DCs), play an important role in the activation of Th1 response. In this study, we investigated the efficacy of a DC-based vaccine against C. posadasii in a mouse model of coccidioidomycosis. We intranasally immunized C57BL6 mice with syngeneic, bone marrow-derived DCs (JAWS II cells) transfected with a cDNA encoding the protective Coccidioides-Ag2/proline-rich Ag. The immunized mice were lethally challenged with C. posadasii through either an i.p. or intranasal route. Upon necropsy after 10 days of infection, fungal burden in lung and spleen of immunized mice was significantly reduced as compared with the control animals. The lung tissue homogenates of immunized animals showed higher levels of IFN-gamma. Histologically, lung tissues of immunized mice were in better condition than the control mice. To further investigate, we studied the biodistribution and trafficking of injected DCs by nuclear imaging techniques. For this purpose, the transfected DCs were radiolabeled with (111)In-oxime. Scintigraphic images showed that most of the label remained in the gastrointestinal tract. A significant amount was also observed in lung, but there were negligible circulating (111)In label in blood. The results suggest that the DCs have a potent immunostimulatory activity, and immunization with DCs transfected with Ag2/proline-rich Ag-cDNA induces protective immunity against C. posadasii in C57BL6 mice.
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Affiliation(s)
- Shanjana Awasthi
- Department of Pathology, University of Texas Health Science Center, San Antonio, TX 78229, USA
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Hausmann J, Pagenstecher A, Baur K, Richter K, Rziha HJ, Staeheli P. CD8 T cells require gamma interferon to clear borna disease virus from the brain and prevent immune system-mediated neuronal damage. J Virol 2005; 79:13509-18. [PMID: 16227271 PMCID: PMC1262614 DOI: 10.1128/jvi.79.21.13509-13518.2005] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Borna disease virus (BDV) frequently causes meningoencephalitis and fatal neurological disease in young but not old mice of strain MRL. Disease does not result from the virus-induced destruction of infected neurons. Rather, it is mediated by H-2(k)-restricted antiviral CD8 T cells that recognize a peptide derived from the BDV nucleoprotein N. Persistent BDV infection in mice is not spontaneously cleared. We report here that N-specific vaccination can protect wild-type MRL mice but not mutant MRL mice lacking gamma interferon (IFN-gamma) from persistent infection with BDV. Furthermore, we observed a significant degree of resistance of old MRL mice to persistent BDV infection that depended on the presence of CD8 T cells. We found that virus initially infected hippocampal neurons around 2 weeks after intracerebral infection but was eventually cleared in most wild-type MRL mice. Unexpectedly, young as well as old IFN-gamma-deficient MRL mice were completely susceptible to infection with BDV. Moreover, neurons in the CA1 region of the hippocampus were severely damaged in most diseased IFN-gamma-deficient mice but not in wild-type mice. Furthermore, large numbers of eosinophils were present in the inflamed brains of IFN-gamma-deficient mice but not in those of wild-type mice, presumably because of increased intracerebral synthesis of interleukin-13 and the chemokines CCL1 and CCL11, which can attract eosinophils. These results demonstrate that IFN-gamma plays a central role in host resistance against infection of the central nervous system with BDV and in clearance of BDV from neurons. They further indicate that IFN-gamma may function as a neuroprotective factor that can limit the loss of neurons in the course of antiviral immune responses in the brain.
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Affiliation(s)
- Jürgen Hausmann
- Department of Virology, Bavarian Nordic GmbH, Fraunhoferstrasse 13, D-82152 Martinsried, Germany.
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Hausmann J, Baur K, Engelhardt KR, Fischer T, Rziha HJ, Staeheli P. Vaccine-induced protection against Borna disease in wild-type and perforin-deficient mice. J Gen Virol 2005; 86:399-403. [PMID: 15659759 DOI: 10.1099/vir.0.80566-0] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Borna disease virus (BDV) can persistently infect the central nervous system and induce CD8+ T-cell-mediated neurological disease in MRL mice. To determine whether specific immune priming would prevent disease, a prime-boost immunization protocol was established in which intramuscular injection of a recombinant parapoxvirus expressing BDV nucleoprotein (BDV-N) was followed by intraperitoneal infection with vaccinia virus expressing BDV-N. Immunized wild-type and perforin-deficient mice remained healthy after intracerebral infection with BDV and contained almost no virus in the brain at 5 weeks post-challenge. Immunization failed to induce resistance against BDV in mice lacking mature CD8+ T cells. Immunization of perforin-deficient mice with a poxvirus vector expressing mutant BDV-N lacking the known CD8+ T-cell epitope did not efficiently block multiplication of BDV in the brain and did not prevent neurological disease, indicating that vaccine-induced immunity to BDV in wild-type and perforin-deficient mice resulted from the action of CD8+ T cells.
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Affiliation(s)
- Jürgen Hausmann
- Department of Virology, University of Freiburg, D-79104 Freiburg, Germany
| | - Karen Baur
- Department of Virology, University of Freiburg, D-79104 Freiburg, Germany
| | - Karin R Engelhardt
- Department of Virology, University of Freiburg, D-79104 Freiburg, Germany
| | - Timo Fischer
- Federal Research Center for Virus Diseases of Animals, Institute for Immunology, D-72076 Tuebingen, Germany
| | - Hanns-Joachim Rziha
- Federal Research Center for Virus Diseases of Animals, Institute for Immunology, D-72076 Tuebingen, Germany
| | - Peter Staeheli
- Department of Virology, University of Freiburg, D-79104 Freiburg, Germany
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