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Kayesh MEH, Hashem MA, Tsukiyama-Kohara K. Toll-Like Receptor and Cytokine Responses to Infection with Endogenous and Exogenous Koala Retrovirus, and Vaccination as a Control Strategy. Curr Issues Mol Biol 2021; 43:52-64. [PMID: 33946297 PMCID: PMC8928999 DOI: 10.3390/cimb43010005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 02/07/2023] Open
Abstract
Koala populations are currently declining and under threat from koala retrovirus (KoRV) infection both in the wild and in captivity. KoRV is assumed to cause immunosuppression and neoplastic diseases, favoring chlamydiosis in koalas. Currently, 10 KoRV subtypes have been identified, including an endogenous subtype (KoRV-A) and nine exogenous subtypes (KoRV-B to KoRV-J). The host’s immune response acts as a safeguard against pathogens. Therefore, a proper understanding of the immune response mechanisms against infection is of great importance for the host’s survival, as well as for the development of therapeutic and prophylactic interventions. A vaccine is an important protective as well as being a therapeutic tool against infectious disease, and several studies have shown promise for the development of an effective vaccine against KoRV. Moreover, CRISPR/Cas9-based genome editing has opened a new window for gene therapy, and it appears to be a potential therapeutic tool in many viral infections, which could also be investigated for the treatment of KoRV infection. Here, we discuss the recent advances made in the understanding of the immune response in KoRV infection, as well as the progress towards vaccine development against KoRV infection in koalas.
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Affiliation(s)
- Mohammad Enamul Hoque Kayesh
- Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan; (M.E.H.K.); (M.A.H.)
- Department of Microbiology and Public Health, Faculty of Animal Science and Veterinary Medicine, Patuakhali Science and Technology University, Barishal 8210, Bangladesh
| | - Md Abul Hashem
- Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan; (M.E.H.K.); (M.A.H.)
- Department of Health, Chattogram City Corporation, Chattogram 4000, Bangladesh
- Laboratory of Animal Hygiene, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan
| | - Kyoko Tsukiyama-Kohara
- Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan; (M.E.H.K.); (M.A.H.)
- Laboratory of Animal Hygiene, Joint Faculty of Veterinary Medicine, Kagoshima University, Kagoshima 890-0065, Japan
- Correspondence: ; Tel.: +81-99-285-3589
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Rose KM, Spada SJ, Broeckel R, McNally KL, Hirsch VM, Best SM, Bouamr F. From Capsids to Complexes: Expanding the Role of TRIM5α in the Restriction of Divergent RNA Viruses and Elements. Viruses 2021; 13:v13030446. [PMID: 33801908 PMCID: PMC7998678 DOI: 10.3390/v13030446] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/05/2021] [Accepted: 03/07/2021] [Indexed: 01/26/2023] Open
Abstract
An evolutionary arms race has been ongoing between retroviruses and their primate hosts for millions of years. Within the last century, a zoonotic transmission introduced the Human Immunodeficiency Virus (HIV-1), a retrovirus, to the human population that has claimed the lives of millions of individuals and is still infecting over a million people every year. To counteract retroviruses such as this, primates including humans have evolved an innate immune sensor for the retroviral capsid lattice known as TRIM5α. Although the molecular basis for its ability to restrict retroviruses is debated, it is currently accepted that TRIM5α forms higher-order assemblies around the incoming retroviral capsid that are not only disruptive for the virus lifecycle, but also trigger the activation of an antiviral state. More recently, it was discovered that TRIM5α restriction is broader than previously thought because it restricts not only the human retroelement LINE-1, but also the tick-borne flaviviruses, an emergent group of RNA viruses that have vastly different strategies for replication compared to retroviruses. This review focuses on the underlying mechanisms of TRIM5α-mediated restriction of retroelements and flaviviruses and how they differ from the more widely known ability of TRIM5α to restrict retroviruses.
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Affiliation(s)
- Kevin M. Rose
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Rockville, MD 20894, USA; (K.M.R.); (S.J.S.); (V.M.H.)
| | - Stephanie J. Spada
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Rockville, MD 20894, USA; (K.M.R.); (S.J.S.); (V.M.H.)
| | - Rebecca Broeckel
- Laboratory of Virology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, MT 59840, USA; (R.B.); (K.L.M.); (S.M.B.)
| | - Kristin L. McNally
- Laboratory of Virology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, MT 59840, USA; (R.B.); (K.L.M.); (S.M.B.)
| | - Vanessa M. Hirsch
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Rockville, MD 20894, USA; (K.M.R.); (S.J.S.); (V.M.H.)
| | - Sonja M. Best
- Laboratory of Virology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, MT 59840, USA; (R.B.); (K.L.M.); (S.M.B.)
| | - Fadila Bouamr
- Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Rockville, MD 20894, USA; (K.M.R.); (S.J.S.); (V.M.H.)
- Correspondence:
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Weinstein-Marom H, Gross G, Levi M, Brayer H, Schachter J, Itzhaki O, Besser MJ. Genetic Modification of Tumor-Infiltrating Lymphocytes via Retroviral Transduction. Front Immunol 2021; 11:584148. [PMID: 33488585 PMCID: PMC7817656 DOI: 10.3389/fimmu.2020.584148] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 11/24/2020] [Indexed: 11/24/2022] Open
Abstract
Adoptive T cell therapy (ACT) holds great promise for cancer treatment. One approach, which has regained wide interest in recent years, employs antitumor T cells isolated from tumor lesions ("tumor-infiltrating lymphocytes" or TIL). It is now appreciated that a considerable proportion of anti-melanoma TIL recognize new HLA-binding peptides resulting from somatic mutations, which occurred during tumor progression. The clinical efficacy of TIL can potentially be improved via their genetic modification, designed to enhance their survival, homing capacity, resistance to suppression, tumor killing ability and additional properties of clinical relevance. Successful implementation of such gene-based strategies critically depends on efficient and reproducible protocols for gene delivery into clinical TIL preparations. Here we describe an optimized protocol for the retroviral transduction of TIL. As the experimental system we employed anti-melanoma TIL cultures prepared from four patients, recombinant retrovirus encoding an anti-CD19 chimeric antigen receptor (CAR) as a model gene of interest and CD19+ and CD19- human cell lines serving as target cells. Transduction on day 7 of the rapid expansion protocol (REP) resulted in 69 ± 8% CAR positive TIL. Transduced, but not untransduced TIL, from the four patients responded robustly to CD19+, but not CD19- cell lines, as judged by substantial secretion of IFN-γ following co-culture. In light of the rekindled interest in antitumor TIL, this protocol can be incorporated into a broad range of gene-based approaches for improving the in-vivo survival and functionality of TIL in the clinical setting.
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Affiliation(s)
- Hadas Weinstein-Marom
- Ella Lemelbaum Institute for Immuno-Oncology, Sheba Medical Center, Ramat Gan, Israel
- Laboratory of Immunology, MIGAL-Galilee Research Institute, Kiryat Shmona, Israel
- Department of Biotechnology, Tel-Hai College, Upper Galilee, Israel
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Gideon Gross
- Laboratory of Immunology, MIGAL-Galilee Research Institute, Kiryat Shmona, Israel
- Department of Biotechnology, Tel-Hai College, Upper Galilee, Israel
| | - Michal Levi
- Ella Lemelbaum Institute for Immuno-Oncology, Sheba Medical Center, Ramat Gan, Israel
| | - Hadar Brayer
- Ella Lemelbaum Institute for Immuno-Oncology, Sheba Medical Center, Ramat Gan, Israel
| | - Jacob Schachter
- Ella Lemelbaum Institute for Immuno-Oncology, Sheba Medical Center, Ramat Gan, Israel
| | - Orit Itzhaki
- Ella Lemelbaum Institute for Immuno-Oncology, Sheba Medical Center, Ramat Gan, Israel
| | - Michal J. Besser
- Ella Lemelbaum Institute for Immuno-Oncology, Sheba Medical Center, Ramat Gan, Israel
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
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Abstract
Tight regulation of immune responses is not only critical for preventing autoimmune diseases but also for preventing immunopathological damage during infections in which overactive immune responses may be more harmful for the host than the pathogen itself. Regulatory T cells (Tregs) play a critical role in this regulation, which was discovered using the Friend retrovirus (FV) mouse model. Subsequent FV studies revealed basic biological information about Tregs, including their suppressive activity on effector cells as well as the molecular mechanisms of virus-induced Treg expansion. Treg suppression not only limits immunopathology but also prevents complete elimination of pathogens contributing to chronic infections. Therefore, Tregs play a complex role in the pathogenesis of persistent retroviral infections. New therapeutic concepts to reactivate effector T-cell responses in chronic viral infections by manipulating Tregs also came from work with the FV model. This knowledge initiated many studies to characterize the role of Tregs in HIV pathogenesis in humans, where a complex picture is emerging. On one hand, Tregs suppress HIV-specific effector T-cell responses and are themselves targets of infection, but on the other hand, Tregs suppress HIV-induced immune hyperactivation and thus slow the infection of conventional CD4+ T cells and limit immunopathology. In this review, the basic findings from the FV mouse model are put into perspective with clinical and basic research from HIV studies. In addition, the few Treg studies performed in the simian immunodeficiency virus (SIV) monkey model will also be discussed. The review provides a comprehensive picture of the diverse role of Tregs in different retroviral infections and possible therapeutic approaches to treat retroviral chronicity and pathogenesis by manipulating Treg responses. Regulatory T cells (Tregs) play a very complex role in retroviral infections, and the balance of beneficial versus detrimental effects from Tregs can change between the acute and chronic phase of infection. Therefore, the development of therapeutics to treat chronic retroviral infections via modulation of Tregs requires detailed information regarding both the positive and negative contributions of Tregs in a particular phase of a specific infection. Here, we review the molecular mechanisms that initiate and control Treg responses in retroviral infections as well as the target cells that are functionally manipulated by Tregs. Basic findings from the Friend retrovirus mouse model that initiated this area of research are put into perspective with clinical and basic research from HIV studies. The targeted manipulation of Treg responses holds a bright future for enhancing immune responses to infections, vaccine responses, and for cure or functional cure of chronic retroviral infections.
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Affiliation(s)
- Kim J. Hasenkrug
- Rocky Mountain Laboratories, NIAID, NIH, Hamilton, Montana, United States of America
| | - Claire A. Chougnet
- Division of Immunobiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- * E-mail:
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Roganowicz MD, Komurlu S, Mukherjee S, Plewka J, Alam SL, Skorupka KA, Wan Y, Dawidowski D, Cafiso DS, Ganser-Pornillos BK, Campbell EM, Pornillos O. TRIM5α SPRY/coiled-coil interactions optimize avid retroviral capsid recognition. PLoS Pathog 2017; 13:e1006686. [PMID: 29040325 PMCID: PMC5667893 DOI: 10.1371/journal.ppat.1006686] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 11/02/2017] [Accepted: 10/10/2017] [Indexed: 12/30/2022] Open
Abstract
Restriction factors are important components of intrinsic cellular defense mechanisms against viral pathogens. TRIM5α is a restriction factor that intercepts the incoming capsid cores of retroviruses such as HIV and provides an effective species-specific barrier to retroviral infection. The TRIM5α SPRY domain directly binds the capsid with only very weak, millimolar-level affinity, and productive capsid recognition therefore requires both TRIM5α dimerization and assembly of the dimers into a multivalent hexagonal lattice to promote avid binding. Here, we explore the important unresolved question of whether the SPRY domains are flexibly linked to the TRIM lattice or more precisely positioned to maximize avidity. Biochemical and biophysical experiments indicate that the linker segment connecting the SPRY domain to the coiled-coil domain adopts an α-helical fold, and that this helical portion mediates interactions between the two domains. Targeted mutations were generated to disrupt the putative packing interface without affecting dimerization or higher-order assembly, and we identified mutant proteins that were nevertheless deficient in capsid binding in vitro and restriction activity in cells. Our studies therefore support a model wherein substantial avidity gains during assembly-mediated capsid recognition by TRIM5α come in part from tailored spacing of tethered recognition domains.
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Affiliation(s)
- Marcin D. Roganowicz
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Sevnur Komurlu
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Santanu Mukherjee
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Jacek Plewka
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Steven L. Alam
- Department of Biochemistry, University of Utah, Salt Lake City, Utah, United States of America
| | - Katarzyna A. Skorupka
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Yueping Wan
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Damian Dawidowski
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, United States of America
| | - David S. Cafiso
- Department of Chemistry, University of Virginia, Charlottesville, Virginia, United States of America
| | - Barbie K. Ganser-Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
| | - Edward M. Campbell
- Department of Microbiology and Immunology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Owen Pornillos
- Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine, Charlottesville, Virginia, United States of America
- * E-mail:
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Hu Y, O’Boyle K, Auer J, Raju S, You F, Wang P, Fikrig E, Sutton RE. Multiple UBXN family members inhibit retrovirus and lentivirus production and canonical NFκΒ signaling by stabilizing IκBα. PLoS Pathog 2017; 13:e1006187. [PMID: 28152074 PMCID: PMC5308826 DOI: 10.1371/journal.ppat.1006187] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2016] [Revised: 02/14/2017] [Accepted: 01/17/2017] [Indexed: 01/05/2023] Open
Abstract
UBXN proteins likely participate in the global regulation of protein turnover, and we have shown that UBXN1 interferes with RIG-I-like receptor (RLR) signaling by interacting with MAVS and impeding its downstream effector functions. Here we demonstrate that over-expression of multiple UBXN family members decreased lentivirus and retrovirus production by several orders-of-magnitude in single cycle assays, at the level of long terminal repeat-driven transcription, and three family members, UBXN1, N9, and N11 blocked the canonical NFκB pathway by binding to Cullin1 (Cul1), inhibiting IκBα degradation. Multiple regions of UBXN1, including its UBA domain, were critical for its activity. Elimination of UBXN1 resulted in early murine embryonic lethality. shRNA-mediated knockdown of UBXN1 enhanced human immunodeficiency virus type 1 (HIV) production up to 10-fold in single cycle assays. In primary human fibroblasts, knockdown of UBXN1 caused prolonged degradation of IκBα and enhanced NFκB signaling, which was also observed after CRISPR-mediated knockout of UBXN1 in mouse embryo fibroblasts. Knockout of UBXN1 significantly up- and down-regulated hundreds of genes, notably those of several cell adhesion and immune signaling pathways. Reduction in UBXN1 gene expression in Jurkat T cells latently infected with HIV resulted in enhanced HIV gene expression, consistent with the role of UBXN1 in modulating the NFκB pathway. Based upon co-immunoprecipitation studies with host factors known to bind Cul1, models are presented as to how UBXN1 could be inhibiting Cul1 activity. The ability of UBXN1 and other family members to negatively regulate the NFκB pathway may be important for dampening the host immune response in disease processes and also re-activating quiescent HIV from latent viral reservoirs in chronically infected individuals.
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Affiliation(s)
- Yani Hu
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Kaitlin O’Boyle
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Jim Auer
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Sagar Raju
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Fuping You
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Penghua Wang
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Erol Fikrig
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Richard E. Sutton
- Section of Infectious Diseases, Department of Internal Medicine, Yale University School of Medicine, New Haven, Connecticut, United States of America
- * E-mail:
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Akhmetzyanova I, Drabczyk M, Neff CP, Gibbert K, Dietze KK, Werner T, Liu J, Chen L, Lang KS, Palmer BE, Dittmer U, Zelinskyy G. PD-L1 Expression on Retrovirus-Infected Cells Mediates Immune Escape from CD8+ T Cell Killing. PLoS Pathog 2015; 11:e1005224. [PMID: 26484769 PMCID: PMC4617866 DOI: 10.1371/journal.ppat.1005224] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2015] [Accepted: 09/22/2015] [Indexed: 01/22/2023] Open
Abstract
Cytotoxic CD8+ T Lymphocytes (CTL) efficiently control acute virus infections but can become exhausted when a chronic infection develops. Signaling of the inhibitory receptor PD-1 is an important mechanism for the development of virus-specific CD8+ T cell dysfunction. However, it has recently been shown that during the initial phase of infection virus-specific CD8+ T cells express high levels of PD-1, but are fully competent in producing cytokines and killing virus-infected target cells. To better understand the role of the PD-1 signaling pathway in CD8+ T cell cytotoxicity during acute viral infections we analyzed the expression of the ligand on retrovirus-infected cells targeted by CTLs. We observed increased levels of PD-L1 expression after infection of cells with the murine Friend retrovirus (FV) or with HIV. In FV infected mice, virus-specific CTLs efficiently eliminated infected target cells that expressed low levels of PD-L1 or that were deficient for PD-L1 but the population of PD-L1high cells escaped elimination and formed a reservoir for chronic FV replication. Infected cells with high PD-L1 expression mediated a negative feedback on CD8+ T cells and inhibited their expansion and cytotoxic functions. These findings provide evidence for a novel immune escape mechanism during acute retroviral infection based on PD-L1 expression levels on virus infected target cells. Virus-specific cytotoxic T cells can eliminate infected cells during acute viral infections, but in chronic infections these cells often become dysfunctional or “exhausted.” The inhibitory receptor PD-1 is involved in the suppression of cytotoxic T cell responses in chronic infections. However, during many acute viral infections cytotoxic T cells up-regulate the PD-1 receptor but initially remain competent in killing virus infected target cells. Here we show that the ligand for PD-1, called PD-L1, can be induced on retrovirus infected cells and that the cells with the highest expression of PD-L1 escaped from cytotoxic T cell killing. Thus, PD-L1high infected target cells accumulated during the course of infection, formed the reservoir of virus persistence, and subsequently mediated a negative feedback on cytotoxic T cells via the PD-1 receptor that ultimately resulted in functional exhaustion of these cells. The current results provide evidence for a novel escape mechanism of viruses from cytotoxic T cell responses and may explain how viral reservoirs are established during chronic infections.
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Affiliation(s)
- Ilseyar Akhmetzyanova
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Malgorzata Drabczyk
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - C. Preston Neff
- University of Colorado, Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Kathrin Gibbert
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Kirsten K. Dietze
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Tanja Werner
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Jia Liu
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- Department of Infectious Diseases, Union Hospital of Tonji Medical College, Huazhong University of Science and Technology, Wuhan, P.R. China
| | - Lieping Chen
- Department of Immunobiology, Yale School of Medicine, Yale University, New Haven, Connecticut, United States of America
| | - Karl S. Lang
- Institute for Immunology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Brent E. Palmer
- University of Colorado, Anschutz Medical Campus, Aurora, Colorado, United States of America
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Gennadiy Zelinskyy
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- * E-mail:
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8
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Abstract
Many posttranscriptional processes are known to regulate gene expression and some of them can act as an antiviral barrier. The nonsense-mediated mRNA decay (NMD) was first identified as an mRNA quality control pathway that triggers rapid decay of mRNA containing premature stop codons due to mutations. NMD is now considered as a general posttranscriptional regulation pathway controlling the expression of a large set of cellular genes. In addition to premature stop codons, many other features including alternative splicing, 5' uORF, long 3' UTR, selenocystein codons, and frameshift are able to promote NMD. Interestingly, many viral mRNAs exhibit some of these features suggesting that virus expression and replication might be sensitive to NMD. Several studies, including recent ones, have shown that this is the case for retroviruses; however, it also appears that retroviruses have developed strategies to overcome NMD in order to protect their genome and ensure a true expression of their genes. As a consequence of NMD inhibition, these viruses also affect the expression of host genes that are prone to NMD, and therefore can potentially trigger pathological effects on infected cells. Here, we review recent studies supporting this newly uncovered function of the NMD pathway as a defense barrier that viruses must overcome in order to replicate.
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Affiliation(s)
- Vincent Mocquet
- Laboratoire de Biologie Moléculaire de la Cellule, Unité Mixte de Recherche 5239, Centre National de la Recherche Scientifique , Ecole Normale Supérieure, Lyon, France
| | - Sebastien Durand
- Laboratoire de Biologie Moléculaire de la Cellule, Unité Mixte de Recherche 5239, Centre National de la Recherche Scientifique , Ecole Normale Supérieure, Lyon, France
| | - Pierre Jalinot
- Laboratoire de Biologie Moléculaire de la Cellule, Unité Mixte de Recherche 5239, Centre National de la Recherche Scientifique , Ecole Normale Supérieure, Lyon, France
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9
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McAllister RM, Gardner MB, Nicolson MO, Gilden RV, Davidson N. RD-114 virus: characterization and identification. Prog Exp Tumor Res 2015; 21:196-215. [PMID: 77028 DOI: 10.1159/000400864] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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10
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11
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12
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Priori ES, Dmochowski L, Myers B, Shigematsu T, Wilbur JR. Studies on a human cell line (ESP-1) producing type C virus particles. Bibl Haematol 2015; 39:720-31. [PMID: 4130401 DOI: 10.1159/000427901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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13
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Kawakami TG, Buckley P, Huff S, McKain D, Fielding H. A comparative study in vitro of a simian virus isolated from spontaneous woolly monkey fibrosarcoma and of a known feline fibrosarcoma virus. Bibl Haematol 2015; 39:236-43. [PMID: 4360156 DOI: 10.1159/000427847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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14
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Dmochowski L. Studies on the interrelationship of type B and type C virus particles in breast cancer and in leukemia. Bibl Haematol 2015; 39:45-60. [PMID: 4360177 DOI: 10.1159/000427800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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15
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Ferrer JF, Avila L, Stock ND. Recent electron microscopic and immunologic studies on bovine cell cultures containing C-type viruses. Bibl Haematol 2015; 39:206-14. [PMID: 4130393 DOI: 10.1159/000427843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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16
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Maruyama K, Dmochowski L, Romero JJ, Wagner SH, Swearingen GR. Studies of human cells infected by leukemia viruses. Bibl Haematol 2015; 39:852-70. [PMID: 4360197 DOI: 10.1159/000427914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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17
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Barski G, Youn JK. Immunizing and interfering action of non-leukemogenic C-type murine virus variants in leukemogenesis. Bibl Haematol 2015; 39:370-6. [PMID: 4360168 DOI: 10.1159/000427864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Gilden R, Bova D, Oroszlan S. Immunochemical studies of the group-specific antigens of mammalian C-type viruses. Bibl Haematol 2015; 39:800-9. [PMID: 4130405 DOI: 10.1159/000427907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Schäfer W, Demsey A, Frank H, Hunsmann G, Lange J, Moennig V, Pister L, Bolognesi DP, Green RW, Luftig RB, Shaper J, Hüper G. Morphological, chemical, and antigenic organization of mammalian C-type viruses. Bibl Haematol 2015:497-515. [PMID: 51634 DOI: 10.1159/000397568] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
New features in the architecture of mammalian type C viruses, in particular knoblike surface projections and hexagonally arranged subunits on the core shell could be demonstrated by electron microscopy, taking advantage of newly developed preparation techniques. As examples, murine leukemia viruses (MuLVs) and newly isolated porcine and bovine C viruses are presented. The major proteins of a MuLV were isolated and partially characterized in chemical terms and with respect to their serological and other biological activities, such as interfering and hemagglutinating (HA) capacity. Most of the characterized proteins could be localized in particular substructures of the virion either by selective removal or isolation of electron microscopically identifiable constituents. The information obtained allowed the design of a more detailed model of mammalian C viruses. Special attention was devoted to the further characterization of interspecies antigens of mammalian C viruses. Different antigenic determinants were revealed. Their distribution allows further subgrouping of mammalian C viruses.
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Osato T, Yamamoto K, Mizuno F, Sugawara K, Aya T. Dual persistence of Epstein-Barr viral and type-C viral genomes in nonproducer human lymphoblastoid cells. Bibl Haematol 2015:585-8. [PMID: 169826 DOI: 10.1159/000397576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Aoki T, Chieco-Bianchi L, Plata EJ, Sendo F, Hollis VW, Kudo T. Host immune response to virus-induced tumors. Some recent concepts. Prog Exp Tumor Res 2015; 19:23-36. [PMID: 4373781 DOI: 10.1159/000395846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Aoki T, Hanafusa H. Cell surface antigens of type C RNA viruses as markers for detection of viruses. Bibl Haematol 2015:493-4. [PMID: 169822 DOI: 10.1159/000397567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Priori ES, Dmochowski L. Immunofluorescence antibodies in human sera to antigens in cells of a type C virus producing human culture of tumor origin. Prog Exp Tumor Res 2015; 19:182-93. [PMID: 4373779 DOI: 10.1159/000395855] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Ferrer JF, Bhatt DM, Marshak RR, Abt DA. Further studies on the antigenic properties and distribution of the putative bovine leukemia virus. Bibl Haematol 2015:59-66. [PMID: 51637 DOI: 10.1159/000397518] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The C-type viruses found in long-term cultures. New Bolton Center (NBC) cell lines, of peripheral lymphocytes from leukemic cattle and in short-term cultures of bovine buffy coat(BC) cells share an immunofluorescent(IF)antigen detected in the cytoplasm of infected cells as well as an antigen demonstrable in gel diffusion experiments. Therefore the viruses from these cultures most likely represent different isolates of the putative bovine leukemia virus (BLV). The BLV precipitin antigen is analogous to the group specific (gs) antigens of the leukemia viruses of other species in that it is soluble, ether resistant, and apparently located within the virion. These observations, together with results showing that the specificity of the BLV precipitin antigen differs from that of the gs antigen of other mammalian leukemia viruses, indicate that the former antigen represents the intraspecies (gs-1) determinant of BLV. Antibodies to the precipitin viral antigen were found in 82% of cattle with leukemia and in 40% of clinically normal adult cattle in multiple-case herds. These groups of animals also had fluorescent antibodies to the virus, but with significantly higher frequencies (100% and 76%, respectively). On the other hand, in leukemia-free herds, precipitating antibodies were not found and the incidence of fluorescent antibodies was only 3%.
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Eckner RJ, Priori ES, Mirand EA, Dmochowski L. ESP-1 helper virus: characterization of type-specific envelope specificities distinct from those of the murine leukemia viruses. Bibl Haematol 2015:607-9. [PMID: 51638 DOI: 10.1159/000397581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Kawakami TG, Buckley PM, dePaoli A, Noll W, Bustad LK. Studies on the prevalence of type C virus associated with gibbon hematopoietic neoplasms. Bibl Haematol 2015:385-9. [PMID: 51628 DOI: 10.1159/000397556] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Gibbon malignancy frequently involves the hematopoietic system and can occur in clusters. Virus isolated from gibbon neoplasms possessed typical type C virus morphology, and the virion measured 100 nm in diameter with an electron-dense nucleoid measuring approximately 75 nm. The virus incorporated 3H-uridine into the nucleic acid and rested at a buoyant density of 1.14-1.16 g/cm3. Intra-and interspecific antigenic determinants were present, and the intraspecific antigenic determinant was shared with the woolly monkey sarcoma virus but not with feline or murine type C viruses. The virus and antibody reactive to the virus are more prevalent in gibbon groups that experience leukemia than those free of hematopoietic neoplasms.
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Barski G. High and low leukemogenic variants of Rauscher virus having a comparable infectivity in vitro. Bibl Haematol 2015:323-6. [PMID: 4376368 DOI: 10.1159/000391723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Barbeau B, Hiscott J, Bazarbachi A, Carvalho E, Jones K, Martin F, Matsuoka M, Murphy EL, Ratner L, Switzer WM, Watanabe T. Conference highlights of the 16th International Conference on Human Retrovirology: HTLV and related retroviruses, 26-30 June 2013, Montreal, Canada. Retrovirology 2014; 11:19. [PMID: 24558960 PMCID: PMC3939404 DOI: 10.1186/1742-4690-11-19] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2014] [Accepted: 02/10/2014] [Indexed: 01/19/2023] Open
Abstract
The 16th International Conference on Human Retrovirology: HTLV and Related Retroviruses was held in Montreal, Québec from June 26th to June 30th, 2013 and was therefore hosted by a Canadian city for the first time. The major topic of the meeting was human T-lymphotropic viruses (HTLVs) and was covered through distinct oral and poster presentation sessions: clinical research, animal models, immunology, molecular and cellular biology, human endogenous and emerging exogenous retroviruses and virology. In this review, highlights of the meeting are provided by different experts for each of these research areas.
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Affiliation(s)
- Benoit Barbeau
- Département des sciences biologiques and BioMed Research Center, Université du Québec à Montréal, Room SB-3335, 2080 St-Urbain, Montréal, Québec, Canada
| | - John Hiscott
- VGTI Florida, Port St., Lucie, FL, USA
- Lady Davis Insitute, Montreal, Canada
| | - Ali Bazarbachi
- Department of Internal Medicine, American University of Beirut, Beirut, Lebanon
| | - Edgar Carvalho
- Immunology Department, Universidade Federal da Bahia (UFBA), Salvador, Bahia, Brazil
| | - Kathryn Jones
- Basic Research Program, Cancer and Inflammation Program, SAIC-Frederick, Inc., Frederick National Laboratory for Cancer Research, Frederick, MD, USA
| | - Fabiola Martin
- Centre for Immunology and Infection, Department of Biology, Hull and York Medical School, University of York, York, UK
| | - Masao Matsuoka
- Laboratory of Virus Control, Institute for Virus Research, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Edward L Murphy
- University of California San Francisco and Blood Systems Research Institute, San Francisco, CA, USA
| | - Lee Ratner
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA
| | - William M Switzer
- Laboratory Branch, Division of HIV/AIDS Prevention, National Center for HIV, Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Toshiki Watanabe
- Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
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Abstract
Retrogenic mice provide a unique system for rapidly analyzing the function of genes in the hematopoietic system. Here, we provide a detailed protocol for the production of retrogenic mice expressing genes coding for T cell receptor (TCR) for antigen. This technology should be easy to establish in any laboratory and should allow for a rapid progress in our understanding of the functional roles of TCR repertoires in immunity.
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Affiliation(s)
- Elisa Kieback
- Max Delbrueck Center for Molecular Medicine, Berlin, Germany
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Dietze KK, Zelinskyy G, Liu J, Kretzmer F, Schimmer S, Dittmer U. Combining regulatory T cell depletion and inhibitory receptor blockade improves reactivation of exhausted virus-specific CD8+ T cells and efficiently reduces chronic retroviral loads. PLoS Pathog 2013; 9:e1003798. [PMID: 24339778 PMCID: PMC3855586 DOI: 10.1371/journal.ppat.1003798] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2013] [Accepted: 10/14/2013] [Indexed: 01/03/2023] Open
Abstract
Chronic infections with human viruses, such as HIV and HCV, or mouse viruses, such as LCMV or Friend Virus (FV), result in functional exhaustion of CD8+ T cells. Two main mechanisms have been described that mediate this exhaustion: expression of inhibitory receptors on CD8+ T cells and expansion of regulatory T cells (Tregs) that suppress CD8+ T cell activity. Several studies show that blockage of one of these pathways results in reactivation of CD8+ T cells and partial reduction in chronic viral loads. Using blocking antibodies against PD-1 ligand and Tim-3 and transgenic mice in which Tregs can be selectively ablated, we compared these two treatment strategies and combined them for the first time in a model of chronic retrovirus infection. Blocking inhibitory receptors was more efficient than transient depletion of Tregs in reactivating exhausted CD8+ T cells and reducing viral set points. However, a combination therapy was superior to any single treatment and further augmented CD8+ T cell responses and resulted in a sustained reduction in chronic viral loads. These results demonstrate that Tregs and inhibitory receptors are non-overlapping factors in the maintenance of chronic viral infections and that immunotherapies targeting both pathways may be a promising strategy to treat chronic infectious diseases. A loss of function, the so-called ‘exhaustion’ of CD8+ T cells, is a hallmark of many chronic infections. The T cell exhaustion is mediated by two main mechanisms, the expression of inhibitory receptors on CD8+ T cells and virus-induced expansion of regulatory T cells (Tregs), which suppress CD8+ T cell activity. Several mouse studies revealed a reactivation of CD8+ T cells and reduction in chronic viral loads after blockage of one of these pathways. These results initiated a number of clinical studies mainly with cancer patients, in which blocking antibodies were used to interfere with inhibitory receptor signaling or drugs that deplete Tregs. For the first time we combined the two therapeutic approaches by using transgenic mice in which Tregs can be selectively ablated and injection of blocking antibodies in a chronic retroviral infection. The results indicate that the combination therapy was superior to any single treatment in further augmenting CD8+ T cell responses and reducing chronic viral loads. Our findings demonstrate that Tregs and inhibitory receptors are non-overlapping factors in the maintenance of chronic viral infections and that immunotherapies targeting both pathways may be a promising new strategy to treat chronic infectious diseases.
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Affiliation(s)
- Kirsten K. Dietze
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
- * E-mail:
| | - Gennadiy Zelinskyy
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Jia Liu
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Freya Kretzmer
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Simone Schimmer
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
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Ohs I, Windmann S, Wildner O, Dittmer U, Bayer W. Interleukin-encoding adenoviral vectors as genetic adjuvant for vaccination against retroviral infection. PLoS One 2013; 8:e82528. [PMID: 24349306 PMCID: PMC3857891 DOI: 10.1371/journal.pone.0082528] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 10/23/2013] [Indexed: 12/22/2022] Open
Abstract
Interleukins (IL) are cytokines with stimulatory and modulatory functions in the immune system. In this study, we have chosen interleukins which are involved in the enhancement of TH2 responses and B cell functions to analyze their potential to improve a prophylactic adenovirus-based anti-retroviral vaccine with regard to antibody and virus-specific CD4+ T cell responses. Mice were vaccinated with an adenoviral vector which encodes and displays the Friend Virus (FV) surface envelope protein gp70 (Ad.pIXgp70) in combination with adenoviral vectors encoding the interleukins IL4, IL5, IL6, IL7 or IL23. Co-application of Ad.pIXgp70 with Ad.IL5, Ad.IL6 or Ad.IL23 resulted in improved protection with high control over FV-induced splenomegaly and reduced viral loads. Mice co-immunized with adenoviral vectors encoding IL5 or IL23 showed increased neutralizing antibody responses while mice co-immunized with Ad.IL6 or Ad.IL23 showed improved FV-specific CD4+ T cell responses compared to mice immunized with Ad.pIXgp70 alone. We show that the co-application of adenoviral vectors encoding specific interleukins is suitable to improve the vaccination efficacy of an anti-retroviral vaccine. Improved protection correlated with improved CD4+ T cell responses and especially with higher neutralizing antibody titers. The co-application of selected interleukin-encoding adenoviral vectors is a valuable tool for vaccination with regard to enhancement of antibody mediated immunity.
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Affiliation(s)
- Inga Ohs
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Sonja Windmann
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Oliver Wildner
- Division of Pharmacovigilance, Paul-Ehrlich-Institut, Langen, Germany
| | - Ulf Dittmer
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
| | - Wibke Bayer
- Institute for Virology, University Hospital Essen, University Duisburg-Essen, Essen, Germany
- * E-mail:
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Blinov VM, Krasnov GS, Shargunov AV, Shurdov MA, Zverev VV. [Mechanisms of retroviral immunosuppressive domain-induced immune modulation]. Mol Biol (Mosk) 2013; 47:707-716. [PMID: 25509343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Immunosuppressive domains (ISD) of viral envelope glycoproteins provide highly pathogenic phenotypes of various retroviruses. ISD interaction with immune cells leads to an inhibition of a response. In the 1980s it was shown that the fragment of ISD comprising of 17 amino acids (named CKS-17) is carrying out such immune modulation. However the underlying mechanisms were not known. The years of thorough research allowed to identify the regulation of Ras-Raf-MEK-MAPK and PI3K-AKT-mTOR cellular pathways as a result of ISD interaction with immune cells. By the way, this leads to decrease of secretion of stimulatory cytokines (e.g., IL-12) and increase of inhibitory, anti-inflammatory ones (e.g., IL-10). One of the receptor tyrosine kinases inducing signal in these pathways acts as the primary target of ISD while other key regulators--cAMP and diacylglycerol (DAG), act as secondary messengers of signal transduction. Immunosuppressive-like domains can be found not only in retroviruses; the presence of ISD within Ebola viral envelope glycoproteins caused extremely hard clinical course of virus-induced hemorrhagic fever. A number of retroviral-origin fragments encoding ISD can be found in the human genome. These regions are expressed in the placenta within genes of syncytins providing a tolerance of mother's immune system to an embryo. The present review is devoted to molecular aspects of retroviral ISD-induced modulation of host immune system.
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Malecek K, Zhong S, McGary K, Yu C, Huang K, Johnson LA, Rosenberg SA, Krogsgaard M. Engineering improved T cell receptors using an alanine-scan guided T cell display selection system. J Immunol Methods 2013; 392:1-11. [PMID: 23500145 DOI: 10.1016/j.jim.2013.02.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2013] [Revised: 02/28/2013] [Accepted: 02/28/2013] [Indexed: 11/18/2022]
Abstract
T cell receptors (TCRs) on T cells recognize peptide-major histocompatibility complex (pMHC) molecules on the surface of antigen presenting cells and this interaction determines the T cell immune response. Due to negative selection, naturally occurring TCRs bind self (tumor) peptides with low affinity and have a much higher affinity for foreign antigens. This complicates isolation of naturally occurring, high affinity TCRs that mediate more effective tumor rejection for therapeutic purposes. An attractive approach to resolve this issue is to engineer high affinity TCRs in vitro using phage, yeast or mammalian TCR display systems. A caveat of these systems is that they rely on a large library by random mutagenesis due to the lack of knowledge regarding the specific interactions between the TCR and pMHC. We have focused on the mammalian retroviral display system because it uniquely allows for direct comparison of TCR-pMHC-binding properties with T-cell activation outcomes. Through an alanine-scanning approach, we are able to quickly map the key amino acid residues directly involved in TCR-pMHC interactions thereby significantly reducing the library size. Using this method, we demonstrate that for a self-antigen-specific human TCR (R6C12) the key residues for pMHC binding are located in the CDR3β region. This information was used as a basis for designing an efficacious TCR CDR3α library that allowed for selection of TCRs with higher avidity than the wild-type as evaluated through binding and activation experiments. This is a direct approach to target specific TCR residues in TCR library design to efficiently engineer high avidity TCRs that may potentially be used to enhance adoptive immunotherapy treatments.
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Affiliation(s)
- Karolina Malecek
- NYU Cancer institute, New York University School of Medicine, NewYork, NY 10016, USA
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Ejaz A, Ammann CG, Werner R, Huber G, Oberhauser V, Hörl S, Schimmer S, Dittmer U, von Laer D, Stoiber H, Bánki Z. Targeting viral antigens to CD11c on dendritic cells induces retrovirus-specific T cell responses. PLoS One 2012; 7:e45102. [PMID: 23028784 PMCID: PMC3444473 DOI: 10.1371/journal.pone.0045102] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2012] [Accepted: 08/13/2012] [Indexed: 11/23/2022] Open
Abstract
Dendritic cells (DC) represent the most potent antigen presenting cells and induce efficient cytotoxic T lymphocyte (CTL) responses against viral infections. Targeting antigens (Ag) to receptors on DCs is a promising strategy to enhance antitumor and antiviral immune responses induced by DCs. Here, we investigated the potential of CD11c-specific single-chain fragments (scFv) fused to an immunodominant peptide of Friend retrovirus for induction of virus-specific T cell responses by DCs. In vitro CD11c-specific scFv selectively targeted viral antigens to DCs and thereby significantly improved the activation of virus-specific T cells. In vaccination experiments DCs loaded with viral Ag targeted to CD11c provided improved rejection of FV-derived tumors and efficiently primed virus-specific CTL responses after virus challenge. Since the induction of strong virus-specific T cell responses is critical in viral infections, CD11c targeted protein vaccines might provide means to enhance the cellular immune response to prophylactic or therapeutic levels.
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Affiliation(s)
- Asim Ejaz
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Christoph G. Ammann
- Department of Internal Medicine I, Innsbruck Medical University, Innsbruck, Austria
| | - Roland Werner
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Georg Huber
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Verena Oberhauser
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Susanne Hörl
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Simone Schimmer
- Institute of Virology, University of Duisburg-Essen, Essen, Germany
| | - Ulf Dittmer
- Institute of Virology, University of Duisburg-Essen, Essen, Germany
| | - Dorothee von Laer
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Heribert Stoiber
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
| | - Zoltán Bánki
- Division of Virology, Innsbruck Medical University, Innsbruck, Austria
- * E-mail:
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Abstract
Mammalian genes and genomes have been shaped by ancient and ongoing challenges from viruses. These genetic imprints can be identified via evolutionary analyses to reveal fundamental details about when (how old), where (which protein domains), and how (what are the functional consequences of adaptive changes) host-virus arms races alter the proteins involved. Just as extreme amino acid conservation can serve to identify key immutable residues in enzymes, positively selected residues point to molecular recognition interfaces between host and viral proteins that have adapted and counter-adapted in a long series of classical Red Queen conflicts. Common rules for the strategies employed by both hosts and viruses have emerged from case studies of innate immunity genes in primates. We are now poised to use these rules to transition from a retrospective view of host-virus arms races to specific predictions about which host genes face pathogen antagonism and how those genetic conflicts transform host and virus evolution.
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Affiliation(s)
- Matthew D Daugherty
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, USA
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Woodland DL. Viral infections: impact on chemokines and chemokine receptors. Viral Immunol 2011; 24:427-8. [PMID: 22149970 DOI: 10.1089/vim.2011.ed.24.6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Audigé A, Hofer U, Dittmer U, van den Broek M, Speck RF. Evaluation of the immunomodulatory and antiviral effects of the cytokine combination IFN-α and IL-7 in the lymphocytic choriomeningitis virus and Friend retrovirus mouse infection models. Viral Immunol 2011; 24:375-85. [PMID: 21929334 DOI: 10.1089/vim.2011.0006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Existing therapies for chronic viral infections are still suboptimal or have considerable side effects, so new therapeutic strategies need to be developed. One option is to boost the host's immune response with cytokines. We have recently shown in an acute ex vivo HIV infection model that co-administration of interferon (IFN)-α and interleukin (IL)-7 allows us to combine the potent anti-HIV activity of IFN-α with the beneficial effects of IL-7 on T-cell survival and function. Here we evaluated the effect of combining IFN-α and IL-7 on viral replication in vivo in the chronic lymphocytic choriomeningitis virus (LCMV) and acute Friend retrovirus (FV) infection models. In the chronic LCMV model, cytokine treatment was started during the early replication phase (i.e., on day 7 post-infection [pi]). Under the experimental conditions used, exogenous IFN-α inhibited FV replication, but had no effect on viral replication in the LCMV model. There was no therapeutic benefit of IL-7 either alone or in combination with IFN-α in either of the two infection models. In the LCMV model, dose-dependent effects of the cytokine combination on T-cell phenotype/function were observed. It is possible that these effects would translate into antiviral activity in re-challenged mice. It is also possible that another type of IFN-α/β or induction of endogenous IFN-α/β alone or in combination with IL-7 would have antiviral activity in the LCMV model. Furthermore, we cannot exclude that some effect on viral titers would have been seen at later time points not investigated here (i.e., beyond day 34 pi). Finally, IFN-α/IL-7 may inhibit the replication of other viruses. Thus it might be worth testing these cytokines in other in vivo models of chronic viral infections.
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Affiliation(s)
- Annette Audigé
- Division of Infectious Diseases and Hospital Epidemiology, University of Zurich, Zurich, Switzerland.
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Abstract
In leukemic mice, the native host's explicit and well-defined immune reactions to the leukemia virus (a strong exogenous antigen) and to leukemia cells (pretending in their native hosts to be protected "self" elements) are extinguished and replaced in GvHD (graft-versus-host disease) by those of the immunocompetent donor cells. In many cases, the GvHD-inducer donors display genetically encoded resistance to the leukemia virus. In human patients only antileukemia and anti-tumor cell immune reactions are mobilized; thus, patients are deprived of immune reactions to a strong exogenous antigen (the elusive human leukemia-sarcoma retroviruses). The innate and adaptive immune systems of mice have to sustain the immunosuppressive effects of leukemia-inducing retroviruses. Human patients due to the lack of leukemiainducing retroviral pathogens (if they exist, they have not as yet been discovered), escape such immunological downgrading. After studying leukemogenic retroviruses in murine and feline (and other mammalian) hosts, it is very difficult to dismiss retroviral etiology for human leukemias and sarcomas. Since no characterized and thus recognized leukemogenic-sarcomagenic retroviral agents are being isolated from the vast majority of human leukemias-sarcomas, the treatment for these conditions in mice and in human patients vastly differ. It is immunological and biological modalities (alpha interferons; vaccines; adoptive lymphocyte therapy) that dominate the treatment of murine leukemias, whereas combination chemotherapy remains the main remission-inducing agent in human leukemias-lymphomas and sarcomas (as humanized monoclonal antibodies and immunotoxins move in). Yet, in this apparently different backgrounds in Mus and Homo, GvHD, as a treatment modality, appears to work well in both hosts, by replacing the hosts' anti-leukemia and anti-tumor immune faculties with those of the donor. The clinical application of GvHD in the treatment of human leukemias-lymphomas and malignant solid tumors remains a force worthy of pursuit, refinement and strengthening. Graft engineering and modifications of the inner immunological environment of the recipient host by the activation or administration of tumor memory T cells, selected Treg cells and natural killer (NKT) cell classes and cytokines, and the improved pharmacotherapy of GvHD without reducing its antitumor efficacy, will raise the value of GvHD to the higher ranks of the effective antitumor immunotherapeutical measures. Clinical interventions of HCT/HSCT (hematopoietic cell/stem cell transplants) are now applicable to an extended spectrum of malignant diseases in human patients, being available to elderly patients, who receive non-myeloablative conditioning, are re-enforced by post-transplant donor lymphocyte (NK cell and immune T cell) infusions and post-transplant vaccinations, and the donor cells may derive from engineered grafts, or from cord blood with reduced GvHD, but increased GvL/GvT-inducing capabilities (graft-versus leukemia/tumor). Post-transplant T cell transfusions are possible only if selected leukemia antigen-specific T cell clones are available. In verbatim quotation: "Ultimately, advances in separation of GvT from GvHD will further enhance the potential of allogeneic HCT as a curative treatment for hematological malignancies" (Rezvani, A.R. and Storb, R.F., Journal of Autoimmunity 30:172-179, 2008 (see in the text)). It may be added: for cure, a combination of the GvL/T effects with new targeted therapeutic modalities, as elaborated on in this article, will be necessary.
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Affiliation(s)
- Joseph G Sinkovics
- The University of South Florida College of Medicine, St. Joseph Hospital's Cancer Institute, Affiliated with the H. L. Moffitt Comprehensive Cancer Center, Tampa, FL 33607-6307, USA.
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Mammerickx M, Burny A, Kettmann R, Portetelle D. A bovine thymic lymphosarcoma case showing a negative serological response to bovine leukemia virus antigens, in a herd with high incidence of enzootic bovine leukosis. Zentralbl Veterinarmed B 2010; 28:733-42. [PMID: 6282011 DOI: 10.1111/j.1439-0450.1981.tb01801.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Mammerickx M, Portetelle D, Burny A, Leunen J. Detection by immunodiffusion- and radioimmunoassay-tests of antibodies to bovine leukemia virus antigens in sera of experimentally infected sheep and cattle. Zentralbl Veterinarmed B 2010; 27:291-303. [PMID: 6252728 DOI: 10.1111/j.1439-0450.1980.tb01694.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Matthaeus W, Straub OC. Detection of precipitating antibodies and identification of bovine leukemia virus antigens by micro counter-current immunoelectrophoresis. Zentralbl Veterinarmed B 2010; 27:61-9. [PMID: 6251674 DOI: 10.1111/j.1439-0450.1980.tb01638.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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45
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Miyazawa T, Yoshikawa R, Golder M, Okada M, Stewart H, Palmarini M. Isolation of an infectious endogenous retrovirus in a proportion of live attenuated vaccines for pets. J Virol 2010; 84:3690-4. [PMID: 20106919 PMCID: PMC2838105 DOI: 10.1128/jvi.02715-09] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Accepted: 01/19/2010] [Indexed: 11/20/2022] Open
Abstract
The genomes of all animal species are colonized by endogenous retroviruses (ERVs). Although most ERVs have accumulated defects that render them incapable of replication, fully infectious ERVs have been identified in various mammals. In this study, we isolated a feline infectious ERV (RD-114) in a proportion of live attenuated vaccines for pets. Isolation of RD-114 was made in two independent laboratories using different detection strategies and using vaccines for both cats and dogs commercially available in Japan or the United Kingdom. This study shows that the methods currently employed to screen veterinary vaccines for retroviruses should be reevaluated.
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Affiliation(s)
- Takayuki Miyazawa
- Laboratory of Signal Transduction, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan, Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, 464 Bearsden Road, Glasgow G61 1QH, Scotland
| | - Rokusuke Yoshikawa
- Laboratory of Signal Transduction, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan, Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, 464 Bearsden Road, Glasgow G61 1QH, Scotland
| | - Matthew Golder
- Laboratory of Signal Transduction, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan, Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, 464 Bearsden Road, Glasgow G61 1QH, Scotland
| | - Masaya Okada
- Laboratory of Signal Transduction, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan, Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, 464 Bearsden Road, Glasgow G61 1QH, Scotland
| | - Hazel Stewart
- Laboratory of Signal Transduction, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan, Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, 464 Bearsden Road, Glasgow G61 1QH, Scotland
| | - Massimo Palmarini
- Laboratory of Signal Transduction, Institute for Virus Research, Kyoto University, 53 Shogoin-Kawaracho, Sakyo-ku, Kyoto 606-8507, Japan, Institute of Comparative Medicine, University of Glasgow Faculty of Veterinary Medicine, 464 Bearsden Road, Glasgow G61 1QH, Scotland
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Abstract
It has been estimated that viruses are etiological agents in approximately 12% of human cancers. Most of these cancers can be attributed to infections by human papillomavirus (HPV), hepatitis B virus (HBV), hepatitis C virus (HCV), Epstein-Barr virus (EBV), and Kaposi's sarcoma-associated herpesvirus (KSHV). Prophylactic vaccines against other pathogenic viruses have an excellent record as public health interventions in terms of safety, effectiveness, and ability to reach economically disadvantaged populations. These considerations should prompt efforts to develop and implement vaccines against oncoviruses. Safe and effective HBV and HPV vaccines, based on virus-like particles, are commercially available, and the major focus is now on vaccine delivery, especially to low-resource settings. HCV and EBV vaccines are under active development, but few clinical trials have been conducted, and none of the candidate vaccines has proven to be sufficiently effective to warrant commercialization. Efforts to develop KSHV vaccines have been more limited.
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Affiliation(s)
- John T Schiller
- Laboratory of Cellular Oncology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892, USA.
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Rutkowski MR, Ho O, Green WR. Defining the mechanism(s) of protection by cytolytic CD8 T cells against a cryptic epitope derived from a retroviral alternative reading frame. Virology 2009; 390:228-38. [PMID: 19539970 DOI: 10.1016/j.virol.2009.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Revised: 03/10/2009] [Accepted: 05/05/2009] [Indexed: 11/18/2022]
Abstract
The biological significance of protective CD8 T-cell-mediated responses against non-traditional alternative reading frame epitopes remains relatively unknown. Cytolytic CD8 T cells (CTL) specific for a non-traditional cryptic MHC class I epitope, SYNTGRFPPL, are critically involved in the protection of mice during infection with the LP-BM5 murine retrovirus. The goal of this study was to determine the functional properties of the protective SYNTGRFPPL-specific CTL during LP-BM5 infection of susceptible BALB/c CD8(-/-) mice. Direct infection experiments and adoptive transfer of CD8 T cells derived from perforin (pfp)(-/-), IFN gamma(-/-), FasL(-/-) and, as a positive control, wild-type BALB/c mice, were utilized to assess the effector mechanisms responsible for protection. Our results indicate that SYNTGRFPPL-specific effector CTL preferentially utilize perforin-mediated cytolysis to provide protection against LP-BM5-induced pathogenesis, whereas CTL production of IFN gamma is not required. Our results also suggest a minimal contribution of FasL/Fas-mediated lysis during the effector response. Collectively, these results provide insight into effector mechanisms utilized by protective CTL directed against non-traditional cryptic epitopes during disease protection.
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Affiliation(s)
- Melanie R Rutkowski
- Department of Microbiology and Immunology, Dartmouth Medical School, Lebanon, NH, USA
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Affiliation(s)
- Susan R Ross
- Department of Microbiology and Abramson Family Cancer Center, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
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Beytut E, Sözmen M, Ergínsoy S. Immunohistochemical detection of pulmonary surfactant proteins and retroviral antigens in the lungs of sheep with pulmonary adenomatosis. J Comp Pathol 2008; 140:43-53. [PMID: 19081577 DOI: 10.1016/j.jcpa.2008.10.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2008] [Revised: 09/18/2008] [Accepted: 10/15/2008] [Indexed: 11/17/2022]
Abstract
The lungs and mediastinal and bronchial lymph nodes from 26 sheep with ovine pulmonary adenomatosis (OPA) were examined. Microscopically, the tumour was disseminated throughout the lungs and displayed acinar or papillary growth. The neoplastic cells were cuboidal or columnar with clear cytoplasm and a low mitotic rate. Retrovirus antigen (Jaagsiekte Sheep Retrovirus Capsid Protein, JSRV CA) was demonstrated in the cytoplasm of tumour cells in the lung and lymph nodes by immunohistochemistry. The neoplastic cells had more diffuse and intense expression of pulmonary surfactant protein-A (SP-A) compared with the expression of SP-B or SP-C. SP-A and SP-B expression was localized to the apical cytoplasm of the neoplastic cells, whereas SP-C was most strongly expressed in the perinuclear area of the tumour cells. In the lungs of two sheep, low numbers of tumour cells expressed Clara cell secretory protein (CCSP). The nuclei of the neoplastic epithelial cells and of the germinal centre lymphocytes within the peribronchiolar lymphoid tissue expressed the proliferating cell nuclear antigen (PCNA). CD3(+) T lymphocytes infiltrated the pulmonary tissue and surrounded the neoplastic foci. The results of this study demonstrate that JSRV continues to replicate in neoplastic cells after they have been transformed, and that the neoplastic cells produce pulmonary surfactant proteins. A local T-cell response occurs within affected lungs.
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Affiliation(s)
- E Beytut
- Department of Pathology, Faculty of Veterinary Medicine, University of Kafkas, Kars, Turkey.
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Abstract
The study of the phenotype of tumours aims to elucidate cell surface alterations that could be used for diagnostic, prognostic or therapeutic purposes. As tumours tend to escape the homeostatic growth control mechanisms of the host, it can be assumed that plasma membrane alterations are also responsible for the antisocial behaviour of tumour cells. Selected features of the transformed phenotype, of fetal or unknown origin, namely tumour-associated antigens, isozymes and growth factors, are discussed in relation to the altered growth pattern of the tumour cell. It is concluded that definitive structure-function relationships have not yet been established, but areas for future investigation are suggested.
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