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Li Z, Xie Q, Zhao F, Huo X, Ren D, Liu Z, Zhou X, Shen G, Zhao J. Exploring GZMK as a prognostic marker and predictor of immunotherapy response in breast cancer: unveiling novel insights into treatment outcomes. J Cancer Res Clin Oncol 2024; 150:286. [PMID: 38833021 PMCID: PMC11150209 DOI: 10.1007/s00432-024-05791-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Accepted: 05/08/2024] [Indexed: 06/06/2024]
Abstract
BACKGROUND Granzyme K (GZMK) is a crucial mediator released by immune cells to eliminate tumor cells, playing significant roles in inflammation and tumorigenesis. Despite its importance, the specific role of GZMK in breast cancer and its mechanisms are not well understood. METHODS We utilized data from the TCGA and GEO databases and employed a range of analytical methods including GO, KEGG, GSEA, ssGSEA, and PPI to investigate the impact of GZMK on breast cancer. In vitro studies, including RT-qPCR, CCK-8 assay, cell cycle experiments, apoptosis assays, Celigo scratch assays, Transwell assays, and immunohistochemical methods, were conducted to validate the effects of GZMK on breast cancer cells. Additionally, Cox regression analysis integrating TCGA and our clinical data was used to develop an overall survival (OS) prediction model. RESULTS Analysis of clinical pathological features revealed significant correlations between GZMK expression and lymph node staging, differentiation grade, and molecular breast cancer subtypes. High GZMK expression was associated with improved OS, progression-free survival (PFS), and recurrence-free survival (RFS), as confirmed by multifactorial Cox regression analysis. Functional and pathway enrichment analyses of genes positively correlated with GZMK highlighted involvement in lymphocyte differentiation, T cell differentiation, and T cell receptor signaling pathways. A robust association between GZMK expression and T cell presence was noted in the breast cancer tumor microenvironment (TME), with strong correlations with ESTIMATEScore (Cor = 0.743, P < 0.001), ImmuneScore (Cor = 0.802, P < 0.001), and StromalScore (Cor = 0.516, P < 0.001). GZMK also showed significant correlations with immune checkpoint molecules, including CTLA4 (Cor = 0.856, P < 0.001), PD-1 (Cor = 0.82, P < 0.001), PD-L1 (Cor = 0.56, P < 0.001), CD48 (Cor = 0.75, P < 0.001), and CCR7 (Cor = 0.856, P < 0.001). Studies indicated that high GZMK expression enhances patient responsiveness to immunotherapy, with higher levels observed in responsive patients compared to non-responsive ones. In vitro experiments confirmed that GZMK promotes cell proliferation, cell division, apoptosis, cell migration, and invasiveness (P < 0.05). CONCLUSION Our study provides insights into the differential expression of GZMK in breast cancer and its potential mechanisms in breast cancer pathogenesis. Elevated GZMK expression is associated with improved OS and RFS, suggesting its potential as a prognostic marker for breast cancer survival and as a predictor of the efficacy of immunotherapy.
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Affiliation(s)
- Zitao Li
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Laboratory for High Altitude Medicine of Qinghai Province, Qinghai University, Xining, 810000, China
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China
| | - Qiqi Xie
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China
| | - Fuxing Zhao
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China
| | - Xinfa Huo
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China
| | - Dengfeng Ren
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China
| | - Zhilin Liu
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China
| | - Xiaofeng Zhou
- Pathology Department, Affiliated Hospital of Qinghai University, Xining, 810000, China
| | - Guoshuang Shen
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China.
| | - Jiuda Zhao
- Research Center for High Altitude Medicine, Key Laboratory of High Altitude Medicine (Ministry of Education), Key Laboratory of Application and Foundation for High Altitude Medicine Research in Qinghai Province (Qinghai-Utah Joint Research Key Lab for High Altitude Medicine), Laboratory for High Altitude Medicine of Qinghai Province, Qinghai University, Xining, 810000, China.
- Breast Disease Diagnosis and Treatment Center of Qinghai University Affiliated Hospital & Affiliated Cancer Hospital of Qinghai University, Xining, 810000, China.
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de Fàbregues O, Sellés M, Ramos-Vicente D, Roch G, Vila M, Bové J. Relevance of tissue-resident memory CD8 T cells in the onset of Parkinson's disease and examination of its possible etiologies: infectious or autoimmune? Neurobiol Dis 2023; 187:106308. [PMID: 37741513 DOI: 10.1016/j.nbd.2023.106308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 05/05/2023] [Accepted: 09/20/2023] [Indexed: 09/25/2023] Open
Abstract
Tissue-resident memory CD8 T cells are responsible for local immune surveillance in different tissues, including the brain. They constitute the first line of defense against pathogens and cancer cells and play a role in autoimmunity. A recently published study demonstrated that CD8 T cells with markers of residency containing distinct granzymes and interferon-γ infiltrate the parenchyma of the substantia nigra and contact dopaminergic neurons in an early premotor stage of Parkinson's disease. This infiltration precedes α-synuclein aggregation and neuronal loss in the substantia nigra, suggesting a relevant role for CD8 T cells in the onset of the disease. To date, the nature of the antigen that initiates the adaptive immune response remains unknown. This review will discuss the role of tissue-resident memory CD8 T cells in brain immune homeostasis and in the onset of Parkinson's disease and other neurological diseases. We also discuss how aging and genetic factors can affect the CD8 T cell immune response and how animal models can be misleading when studying human-related immune response. Finally, we speculate about a possible infectious or autoimmune origin of Parkinson's disease.
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Affiliation(s)
- Oriol de Fàbregues
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute, Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Catalonia, Spain; Movement Disorders Unit, Neurology Department, Vall d'Hebron University Hospital
| | - Maria Sellés
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute, Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Catalonia, Spain
| | - David Ramos-Vicente
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute, Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Catalonia, Spain
| | - Gerard Roch
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute, Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Catalonia, Spain
| | - Miquel Vila
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute, Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Catalonia, Spain; Department of Biochemistry and Molecular Biology, Autonomous University of Barcelona, Barcelona, Catalonia, Spain; Aligning Science Across Parkinson's (ASAP) Collaborative Research Network, Chevy Chase, MD, USA; Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Catalonia, Spain
| | - Jordi Bové
- Neurodegenerative Diseases Research Group, Vall d'Hebron Research Institute, Center for Networked Biomedical Research on Neurodegenerative Diseases (CIBERNED), Barcelona, Catalonia, Spain.
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3
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Bouwman AC, van Daalen KR, Crnko S, Ten Broeke T, Bovenschen N. Intracellular and Extracellular Roles of Granzyme K. Front Immunol 2021; 12:677707. [PMID: 34017346 PMCID: PMC8129556 DOI: 10.3389/fimmu.2021.677707] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 04/21/2021] [Indexed: 12/30/2022] Open
Abstract
Granzymes are a family of serine proteases stored in granules inside cytotoxic cells of the immune system. Granzyme K (GrK) has been only limitedly characterized and knowledge on its molecular functions is emerging. Traditionally GrK is described as a granule-secreted, pro-apoptotic serine protease. However, accumulating evidence is redefining the functions of GrK by the discovery of novel intracellular (e.g. cytotoxicity, inhibition of viral replication) and extracellular roles (e.g. endothelial activation and modulation of a pro-inflammatory immune cytokine response). Moreover, elevated GrK levels are associated with disease, including viral and bacterial infections, airway inflammation and thermal injury. This review aims to summarize and discuss the current knowledge of i) intracellular and extracellular GrK activity, ii) cytotoxic and non-cytotoxic GrK functioning, iii) the role of GrK in disease, and iv) GrK as a potential therapeutic target.
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Affiliation(s)
- Annemieke C Bouwman
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Kim R van Daalen
- Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, Cambridge, United Kingdom
| | - Sandra Crnko
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Toine Ten Broeke
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Niels Bovenschen
- Department of Pathology, University Medical Center Utrecht, Utrecht, Netherlands.,Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
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4
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Kedzierska K, Koutsakos M. The ABC of Major Histocompatibility Complexes and T Cell Receptors in Health and Disease. Viral Immunol 2021; 33:160-178. [PMID: 32286182 PMCID: PMC7185345 DOI: 10.1089/vim.2019.0184] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
A seminal discovery of major histocompatibility complex (MHC) restriction in T cell recognition by Peter Doherty and Rolf Zinkernagel has led to 45 years of exciting research on the mechanisms governing peptide MHC (pMHC) recognition by T cell receptors (TCRs) and their importance in health and disease. T cells provide a significant level of protection against viral, bacterial, and parasitic infections, as well as tumors, hence, the generation of protective T cell responses is a primary goal for cell-mediated vaccines and immunotherapies. Understanding the mechanisms underlying generation of optimal high-avidity effector T cell responses, memory development, maintenance, and recall is of major importance for the rational design of preventative and therapeutic vaccines/immunotherapies. In this review, we summarize the lessons learned over the last four decades and outline our current understanding of the basis and consequences of pMHC/TCR interactions on T cell development and function, and TCR diversity and composition, driving better clinical outcomes and prevention of viral escape. We also discuss the current models of T cell memory formation and determinants of immunodominant T cell responses in animal models and humans. As TCR composition and diversity can affect both the protective capacity of T cells and protection against viral escape, defining the spectrum of TCR selection has implications for improving the functional efficacy of effector T cell responsiveness and memory formation.
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Affiliation(s)
- Katherine Kedzierska
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
| | - Marios Koutsakos
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, University of Melbourne, Melbourne, Australia
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5
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Abstract
Evaluation of cell-mediated immunity (CMI) is a significant component in any assessment designed to predict the full range of potential immunotoxic risk underlying health risks. Among measures of CMI, the cytotoxic T-lymphocyte (CTL) response is recognized as perhaps the most relevant functional measure that reflects cell-mediated acquired immune defense against viral infections and cancer. The CTL response against T-dependent antigens requires the cooperation of at least three different major categories of immune cells. These include professional antigen-presenting cells (e.g., dendritic cells), CD4+ T helper lymphocytes, and CD8+ T effector lymphocytes. It is also among the few functional responses dependent on and, hence, capable of evaluating effective antigen presentation via both class I and class II molecules of the major histocompatibility complex (MHC). For this reason, the CTL assay is an excellent candidate for evaluation of potential immunotoxicity. This chapter provides an example of a mouse CTL assay against influenza virus that has been utilized for this purpose.
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7
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Abstract
The human genome encodes seven isoforms of importin α which are grouped into three subfamilies known as α1, α2 and α3. All isoforms share a fundamentally conserved architecture that consists of an N-terminal, autoinhibitory, importin-β-binding (IBB) domain and a C-terminal Arm (Armadillo)-core that associates with nuclear localization signal (NLS) cargoes. Despite striking similarity in amino acid sequence and 3D structure, importin-α isoforms display remarkable substrate specificity in vivo. In the present review, we look at key differences among importin-α isoforms and provide a comprehensive inventory of known viral and cellular cargoes that have been shown to associate preferentially with specific isoforms. We illustrate how the diversification of the adaptor importin α into seven isoforms expands the dynamic range and regulatory control of nucleocytoplasmic transport, offering unexpected opportunities for pharmacological intervention. The emerging view of importin α is that of a key signalling molecule, with isoforms that confer preferential nuclear entry and spatiotemporal specificity on viral and cellular cargoes directly linked to human diseases.
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8
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Kurioka A, Ussher JE, Cosgrove C, Clough C, Fergusson JR, Smith K, Kang YH, Walker LJ, Hansen TH, Willberg CB, Klenerman P. MAIT cells are licensed through granzyme exchange to kill bacterially sensitized targets. Mucosal Immunol 2015; 8:429-40. [PMID: 25269706 PMCID: PMC4288950 DOI: 10.1038/mi.2014.81] [Citation(s) in RCA: 282] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 07/26/2014] [Indexed: 02/06/2023]
Abstract
Mucosal-associated invariant T (MAIT) cells are an innate-like T-cell population restricted by the non-polymorphic, major histocompatibility complex class I-related protein 1, MR1. MAIT cells are activated by a broad range of bacteria through detection of riboflavin metabolites bound by MR1, but their direct cytolytic capacity upon recognition of cognate target cells remains unclear. We show that resting human MAIT cells are uniquely characterized by a lack of granzyme (Gr) B and low perforin expression, key granule proteins required for efficient cytotoxic activity, but high levels of expression of GrA and GrK. Bacterial activation of MAIT cells rapidly induced GrB and perforin, licensing these cells to kill their cognate target cells. Using a novel flow cytometry-based killing assay, we show that licensed MAIT cells, but not ex vivo MAIT cells from the same donors, can efficiently kill Escherichia coli-exposed B-cell lines in an MR1- and degranulation-dependent manner. Finally, we show that MAIT cells are highly proliferative in response to antigenic and cytokine stimulation, maintaining high expression of GrB, perforin, and GrA, but reduced expression of GrK following antigenic proliferation. The tightly regulated cytolytic capacity of MAIT cells may have an important role in the control of intracellular bacterial infections, such as Mycobacterium tuberculosis.
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Affiliation(s)
- A Kurioka
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK,
| | - J E Ussher
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - C Cosgrove
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - C Clough
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - J R Fergusson
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - K Smith
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Y-H Kang
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - L J Walker
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - T H Hansen
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, Missouri, USA
| | - C B Willberg
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK,National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - P Klenerman
- Peter Medawar Building for Pathogen Research, Nuffield Department of Medicine, University of Oxford, Oxford, UK,National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
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9
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Lee CC, Kim BS, Wu CC, Lin TL. Bursal transcriptome of chickens protected by DNA vaccination versus those challenged with infectious bursal disease virus. Arch Virol 2014; 160:69-80. [PMID: 25267176 DOI: 10.1007/s00705-014-2232-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Accepted: 09/09/2014] [Indexed: 11/26/2022]
Abstract
Infectious bursal disease virus (IBDV) infection destroys the bursa of Fabricius, causing immunosuppression and rendering chickens susceptible to secondary bacterial or viral infections. IBDV large-segment-protein-expressing DNA has been shown to confer complete protection of chickens from infectious bursal disease (IBD). The purpose of the present study was to compare DNA-vaccinated chickens and unvaccinated chickens upon IBDV challenge by transcriptomic analysis of bursa regarding innate immunity, inflammation, immune cell regulation, apoptosis and glucose transport. One-day-old specific-pathogen-free chickens were vaccinated intramuscularly three times at weekly intervals with IBDV large-segment-protein-expressing DNA. Chickens were challenged orally with 8.2 × 10(2) times the egg infective dose (EID)50 of IBDV strain variant E (VE) one week after the last vaccination. Bursae collected at 0.5, 1, 3, 5, 7, and 10 days post-challenge (dpc) were subjected to real-time RT-PCR quantification of bursal transcripts related to innate immunity, inflammation, immune cell regulation, apoptosis and glucose transport. The expression levels of granzyme K and CD8 in DNA-vaccinated chickens were significantly (p < 0.05) higher than those in unvaccinated chickens upon IBDV challenge at 0.5 or 1 dpc. The expression levels of other genes involved in innate immunity, inflammation, immune cell regulation, apoptosis and glucose transport were not upregulated or downregulated in DNA-vaccinated chickens during IBDV challenge. Bursal transcripts related to innate immunity and inflammation, including TLR3, MDA5, IFN-α, IFN-β, IRF-1, IRF-10, IL-1β, IL-6, IL-8, iNOS, granzyme A, granzyme K and IL-10, were upregulated or significantly (p < 0.05) upregulated at 3 dpc and later in unvaccinated chickens challenged with IBDV. The expression levels of genes related to immune cell regulation, apoptosis and glucose transport, including CD4, CD8, IL-2, IFN-γ, IL-12(p40), IL-18, GM-CSF, GATA-3, p53, glucose transporter-2 and glucose transporter-3, were upregulated or significantly (p < 0.05) upregulated at 3 dpc and later in unvaccinated chickens challenged with IBDV. Taken together, the results indicate that the bursal transcriptome involved in innate immunity, inflammation, immune cell regulation, apoptosis and glucose transport, except for granzyme K and CD8, was not differentially expressed in DNA-vaccinated chickens protected from IBDV challenge.
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Affiliation(s)
- Chih-Chun Lee
- Department of Comparative Pathobiology, Purdue University, 406 S. University St, West Lafayette, IN, 47907, USA
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10
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La Gruta NL, Turner SJ. T cell mediated immunity to influenza: mechanisms of viral control. Trends Immunol 2014; 35:396-402. [PMID: 25043801 DOI: 10.1016/j.it.2014.06.004] [Citation(s) in RCA: 117] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Revised: 06/20/2014] [Accepted: 06/20/2014] [Indexed: 12/31/2022]
Abstract
Infection with influenza A virus (IAV) is a major cause of worldwide morbidity and mortality. Recent findings indicate that T cell immunity is key to limiting severity of disease arising from IAV infection, particularly in instances where antibody immunity is ineffective. As such, there is a need to understand better the mechanisms that mediate effective IAV-specific cellular immunity, especially given that T cell immunity must form an integral part of any vaccine designed to elicit crossreactive immunity against existing and new strains of influenza virus. Here, we review the current understanding of cellular immunity to IAV, highlighting recent findings that demonstrate important roles for both CD4+ and CD8+ T cell immunity in protection from IAV-mediated disease.
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Affiliation(s)
- Nicole L La Gruta
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria, 3010, Australia
| | - Stephen J Turner
- Department of Microbiology and Immunology, The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, Victoria, 3010, Australia.
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11
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Blessing or curse? Proteomics in granzyme research. Proteomics Clin Appl 2014; 8:351-81. [DOI: 10.1002/prca.201300096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2013] [Revised: 11/29/2013] [Accepted: 12/21/2013] [Indexed: 01/08/2023]
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12
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Granzyme K synergistically potentiates LPS-induced cytokine responses in human monocytes. Proc Natl Acad Sci U S A 2014; 111:5974-9. [PMID: 24711407 DOI: 10.1073/pnas.1317347111] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Granzymes are serine proteases released by cytotoxic lymphocytes to induce apoptosis in virus-infected cells and tumor cells. Evidence is emerging that granzymes also play a role in controlling inflammation. Granzyme serum levels are elevated in patients with autoimmune diseases and infections, including sepsis. However, the function of extracellular granzymes in inflammation largely remains unknown. Here, we show that granzyme K (GrK) binds to Gram-negative bacteria and their cell-wall component lipopolysaccharide (LPS). GrK synergistically enhances LPS-induced cytokine release in vitro from primary human monocytes and in vivo in a mouse model of LPS challenge. Intriguingly, these extracellular effects are independent of GrK catalytic activity. GrK disaggregates LPS from micelles and augments LPS-CD14 complex formation, thereby likely boosting monocyte activation by LPS. We conclude that extracellular GrK is an unexpected direct modulator of LPS-TLR4 signaling during the antimicrobial innate immune response.
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Plasman K, Maurer-Stroh S, Ahmad J, Hao H, Kaiserman D, Sirota FL, Jonckheere V, Bird PI, Gevaert K, Van Damme P. Conservation of the extended substrate specificity profiles among homologous granzymes across species. Mol Cell Proteomics 2013; 12:2921-34. [PMID: 23788529 DOI: 10.1074/mcp.m113.028670] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Granzymes are structurally related serine proteases involved in cell death and immunity. To date four out of five human granzymes have assigned orthologs in mice; however for granzyme H, no murine ortholog has been suggested and its role in cytotoxicity remains controversial. Here, we demonstrate that, as is the case for granzyme C, human granzyme H is an inefficient cytotoxin that together with their similar pattern of GrB divergence and functional similarity strongly hint to their orthologous relationship. Besides analyzing the substrate specificity profile of granzyme H by substrate phage display, substrate cleavage susceptibility of human granzyme H and mouse granzyme C was assessed on a proteome-wide level. The extended specificity profiles of granzymes C and H (i.e. beyond cleavage positions P4-P4') match those previously observed for granzyme B. We demonstrate conservation of these extended specificity profiles among various granzymes as granzyme B cleavage susceptibility of an otherwise granzyme H/C specific cleavage site can simply be conferred by altering the P1-residue to aspartate, the preferred P1-residue of granzyme B. Our results thus indicate a conserved, but hitherto underappreciated specificity-determining role of extended protease-substrate contacts in steering cleavage susceptibility.
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Affiliation(s)
- Kim Plasman
- Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium
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14
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Hildemann SK, Eberlein J, Davenport B, Nguyen TT, Victorino F, Homann D. High efficiency of antiviral CD4(+) killer T cells. PLoS One 2013; 8:e60420. [PMID: 23565245 PMCID: PMC3614903 DOI: 10.1371/journal.pone.0060420] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 01/10/2013] [Indexed: 12/22/2022] Open
Abstract
The destruction of infected cells by cytotxic T lymphocytes (CTL) is integral to the effective control of viral and bacterial diseases, and CTL function at large has long been regarded as a distinctive property of the CD8(+)T cell subset. In contrast, and despite their first description more than three decades ago, the precise contribution of cytotoxic CD4(+)T cells to the resolution of infectious diseases has remained a matter of debate. In particular, the CTL activity of pathogen-specific CD4(+) "helper" T cells constitutes a single trait among a diverse array of other T cell functionalities, and overall appears considerably weaker than the cytolytic capacity of CD8(+) effector T cells. Here, using an in vivo CTL assay, we report that cytotoxic CD4(+)T cells are readily generated against both viral and bacterial pathogens, and that the efficiency of MHC-II-restricted CD4(+)T cell killing adjusted for effector:target cell ratios, precise specificities and functional avidities is comparable in magnitude to that of CD8(+)T cells. In fact, the only difference between specific CD4(+) and CD8(+)T cells pertains to the slightly delayed killing kinetics of the former demonstrating that potent CTL function is a cardinal property of both antiviral CD8(+) and CD4(+)T cells.
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Affiliation(s)
- Steven K. Hildemann
- University Clinic for Cardiology and Angiology I, University Heart Center, Freiburg-Bad Krozingen, Germany
- Merck Research Laboratories/MSD Global Clinical Trial Operations, Haar, Germany
| | - Jens Eberlein
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, Colorado, United States of America
| | - Bennett Davenport
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, Colorado, United States of America
- Integrated Department of Immunology, University of Colorado Denver and National Jewish Health, Denver, Colorado, United States of America
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado, United States of America
| | - Tom T. Nguyen
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, Colorado, United States of America
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado, United States of America
| | - Francisco Victorino
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, Colorado, United States of America
- Integrated Department of Immunology, University of Colorado Denver and National Jewish Health, Denver, Colorado, United States of America
| | - Dirk Homann
- Barbara Davis Center for Childhood Diabetes, University of Colorado Denver, Aurora, Colorado, United States of America
- Integrated Department of Immunology, University of Colorado Denver and National Jewish Health, Denver, Colorado, United States of America
- Department of Anesthesiology, University of Colorado Denver, Aurora, Colorado, United States of America
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La Gruta N, Kelso A, Brown LE, Chen W, Jackson DC, Turner SJ. Role of CD8(+) T-cell immunity in influenza infection: potential use in future vaccine development. Expert Rev Respir Med 2012; 3:523-37. [PMID: 20477341 DOI: 10.1586/ers.09.44] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Continued circulation of the highly pathogenic avian H5N1 influenza A virus has many people worried that an influenza pandemic is imminent. Compounding this is the realization that H5N1 vaccines based on current influenza vaccine technology (designed to generate protective antibody responses) may be suboptimal at providing protection. As a consequence, there is recent interest in vaccine strategies that elicit cellular immunity, particularly the cytotoxic T lymphocyte response, in an effort to provide protection against a potential pandemic. A major issue is the lack of information about the precise role that these 'hitmen' of the immune system have in protecting against both pandemic and seasonal influenza. We need to know more about how the induction and maintenance of cytotoxic T lymphocytes after influenza infection can impact protection from further infection. The challenge is then to use this information in the design of vaccines that will protect against pandemic influenza and will help optimize CD8(+) killer T-cell responses in other infections.
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Affiliation(s)
- Nicole La Gruta
- Department of Microbiology and Immunology, The University of Melbourne, Royal Parade, Parkville, Victoria 3010, Australia
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Zhong C, Li C, Wang X, Toyoda T, Gao G, Fan Z. Granzyme K inhibits replication of influenza virus through cleaving the nuclear transport complex importin α1/β dimer of infected host cells. Cell Death Differ 2011; 19:882-90. [PMID: 22139131 DOI: 10.1038/cdd.2011.178] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The influenza A virus is a causative agent of influenza, which infects human cells and uses host factors to accomplish viral genome replication as part of its life cycle. The nucleoprotein (NP) and PB2 of the influenza virus associate with importin α1 to gain access to the host nucleus through a ternary import complex. Killer cell-mediated cytotoxicity is the primary mechanism of eliminating the influenza virus. Here, we showed that lymphokine-activated killer cells participated in the elimination of the influenza virus. Granzyme (Gzm) K inhibition elevated viral replication in vitro and aggravated viral infection in vivo. We identified that importin α1 and its transport partner protein importin β are physiological substrates of GzmK. Proteolysis of these two substrates wrecked their association to generate the importin α1/β dimer and disrupted transportation of viral NP to the nucleus, leading to inhibition of influenza virus replication.
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Affiliation(s)
- C Zhong
- CAS Key Laboratory of Infection and Immunity and Center for Infection and Immunity, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
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17
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Abstract
Granzymes (gzms) are key components of T-killer (Tc) cells believed to mediate pro-apoptotic activities. Recent evidence suggests that gzms also possess non-cytotoxic activities that contribute to host defense. In this study, we show that Tc cells from lymphocytic choriomeningitis virus (LCMV)-infected wild-type (wt) and gzm A/B-deficient mice express similar levels of gzmK protein, with both mouse strains efficiently controlling infection. GzmK, in recombinant form or secreted by ex vivo-derived LCMV-immune gzmAxB(-/-) Tc cells, lacks pro-apoptotic activity. Instead, gzmK induces primary mouse macrophages to process and secrete interleukin-1β, independent of the ATP receptor P2X(7). Together with the finding that IL-1Ra (Anakinra) treatment inhibits virus elimination but not generation of cytotoxic Tc cells in wt mice, the data suggest that Tc cells control LCMV through non-cytotoxic processes that involve gzmK.
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18
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Olson MR, Russ BE, Doherty PC, Turner SJ. The role of epigenetics in the acquisition and maintenance of effector function in virus-specific CD8 T cells. IUBMB Life 2010; 62:519-26. [PMID: 20552633 DOI: 10.1002/iub.351] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CD8(+) T cells are critical for protecting the body from infectious disease. To achieve this protection, CD8(+) T cells must undergo a highly involved process of differentiation that involves the activation of naïve/quiescent cells followed by robust rounds of cell division and the acquisition of effector functions that mediate viral clearance. After the pathogen is eliminated, a small number of these cells survive into long-lived memory and maintain the capacity to respond rapidly and reacquire effector function after secondary exposure to their cognate antigen. This review focuses on how CD8(+) T cells acquire and regulate effector functions and how the capacity to produce effector molecules is maintained into memory.
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Affiliation(s)
- Matthew R Olson
- Department of Microbiology and Immunology, University of Melbourne, Parkville, VIC, Australia.
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19
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Kohlmeier JE, Cookenham T, Roberts AD, Miller SC, Woodland DL. Type I interferons regulate cytolytic activity of memory CD8(+) T cells in the lung airways during respiratory virus challenge. Immunity 2010; 33:96-105. [PMID: 20637658 DOI: 10.1016/j.immuni.2010.06.016] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 05/03/2010] [Accepted: 05/19/2010] [Indexed: 12/26/2022]
Abstract
Memory CD8(+) T cells in the lung airways provide protection from secondary respiratory virus challenge by limiting early viral replication. Here, we demonstrate that although airway-resident memory CD8(+) T cells were poorly cytolytic, memory CD8(+) T cells recruited to the airways early during a recall response showed markedly enhanced cytolytic ability. This enhanced lytic activity did not require cognate antigen stimulation, but rather was dependent on STAT1 transcription factor signaling through the interferon-alpha receptor (Ifnar1), resulting in the antigen-independent expression of granzyme B protein in both murine and human virus-specific T cells. Signaling through Ifnar1 was required for the enhanced lytic activity and control of early viral replication by memory CD8(+) T cells in the lung airways. These findings demonstrate that innate inflammatory signals act directly on memory T cells, enabling them to rapidly destroy infected host cells once they enter infected tissues.
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Affiliation(s)
- Jacob E Kohlmeier
- Trudeau Institute, 154 Algonquin Avenue, Saranac Lake, NY 12983, USA.
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20
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Abstract
Cytotoxic lymphocytes are armed with granules that are released in the granule-exocytosis pathway to kill tumor cells and virus-infected cells. Cytotoxic granules contain the pore-forming protein perforin and a family of structurally homologues serine proteases called granzymes. While perforin facilitates the entry of granzymes into a target cell, the latter initiate distinct apoptotic routes. Granzymes are also implicated in extracellular functions such as extracellular matrix degradation, immune regulation, and inflammation. The family of human granzymes consists of five members, of which granzyme A and B have been studied most extensively. Recently, elucidation of the specific characteristics of the other three human granzymes H, K, and M, also referred to as orphan granzymes, have started. In this review, we summarize and discuss what is currently known about the biology of the human orphan granzymes.
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Affiliation(s)
- Niels Bovenschen
- Department of Pathology, University Medical Center Utrecht, 3584 CX Utrecht, The Netherlands.
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21
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Hirata Y, Inagaki H, Kawada T. Recombinant human progranzyme 3 expressed in Escherichia coli for analysis of its activation mechanism. Microbiol Immunol 2010; 54:98-104. [PMID: 20377743 DOI: 10.1111/j.1348-0421.2009.00187.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gr3 is reported to play an important role in defense against viral infection. Although it is known that Gr3 is synthesized as a proenzyme and activated in the cytotoxic granules of NK cells and CTL, the activation mechanism is not clearly understood. In an attempt to analyze the activation mechanism of human Gr3, a recombinant pro-Gr3 was expressed in the periplasm of E. coli and purified to homogeneity. On SDS-PAGE the recombinant pro-Gr3 showed a slightly higher molecular weight than the enzymatically active Gr3, because the former possesses a small propeptide at its N-terminal. The recombinant pro-Gr3 was enzymatically inactive. It could be activated by treatment with cathepsin C, which concomitantly decreased the molecular weight to that of active Gr3. The proteolytic reaction of cathepsin C did not continue after one dipeptide had been removed, indicating that the recombinant pro-Gr3 had the native conformation without any refolding process. The recombinant pro-Gr3 would be a valuable tool for analyzing the activation mechanism and exploring other activating enzymes besides cathepsin C.
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Affiliation(s)
- Yukiyo Hirata
- Department of Hygiene and Public Health, Nippon Medical School, Bunkyo-ku, Tokyo 113-8602, Japan.
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22
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Abstract
Granzyme A (GzmA) is the most abundant serine protease in killer cell cytotoxic granules. GzmA activates a novel programed cell death pathway that begins in the mitochondrion, where cleavage of NDUFS3 in electron transport complex I disrupts mitochondrial metabolism and generates reactive oxygen species (ROS). ROS drives the endoplasmic reticulum-associated SET complex into the nucleus, where it activates single-stranded DNA damage. GzmA also targets other important nuclear proteins for degradation, including histones, the lamins that maintain the nuclear envelope, and several key DNA damage repair proteins (Ku70, PARP-1). Cells that are resistant to the caspases or GzmB by overexpressing bcl-2 family anti-apoptotic proteins or caspase or GzmB protease inhibitors are sensitive to GzmA. By activating multiple cell death pathways, killer cells provide better protection against a variety of intracellular pathogens and tumors. GzmA also has proinflammatory activity; it activates pro-interleukin-1beta and may also have other proinflammatory effects that remain to be elucidated.
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Affiliation(s)
- Judy Lieberman
- Immune Disease Institute and Program in Cellular and Molecular Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA, USA.
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23
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Abstract
In kidney allografts, T cell mediated rejection (TCMR) is characterized by infiltration of the interstitium by T cells and macrophages, intense IFNG and TGFB effects, and epithelial deterioration. Recent experimental and clinical studies provide the basis for a provisional model for TCMR. The model proposes that the major unit of cognate recognition in TCMR is effector T cells engaging donor antigen on macrophages. This event creates the inflammatory compartment that recruits effector and effector memory CD4 and CD8 T cells, both cognate and noncognate, and macrophage precursors. Cognate T cells cross the donor microcirculation to enter the interstitium but spare the microcirculation. Local inflammation triggers dedifferentiation of the adjacent epithelium (e.g. loss of transporters and expression of embryonic genes) rather than cell death, via mechanisms that do not require known T-cell cytotoxic mechanisms or direct contact of T cells with the epithelium. Local epithelial changes trigger a response of the entire nephron and a second wave of dedifferentiation. The dedifferentiated epithelium is unable to exclude T cells, which enter to produce tubulitis lesions. Thus TCMR is a cognate recognition-based process that creates local inflammation and epithelial dedifferentiation, stereotyped nephron responses, and tubulitis, and if untreated causes irreversible nephron loss.
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Affiliation(s)
- P F Halloran
- Department of Medicine, Division of Nephrology and Immunology, Alberta Transplant Applied Genomics Centre, University of Alberta, Edmonton, Canada.
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24
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Olson M, Russ B, Doherty P, Turner S, Stambas J. Influenza A virus-specific CD8 T-cell responses: from induction to function. Future Virol 2010; 5:175-183. [PMID: 21544256 DOI: 10.2217/fvl.10.3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Seasonal influenza virus infection is a leading cause of illness and mortality in young children and the elderly each year. Current influenza vaccines generate protective antibody responses; however, these must be given annually to provide protection against serologically distinct viruses. By contrast, CD8(+) T cells are capable of recognizing conserved antigenic determinants within the influenza virion and, as such, may provide protection against a number of variant strains of the virus. CD8(+) T cells play a critical key role in controlling and resolving influenza virus infections via the production of cytokines and cytolytic mediators. This article focuses on the induction of the influenza-specific CD8(+) T-cell response and how these cells acquire and maintain effector function after induction. Moreover, we discuss how cytotoxic T-lymphocyte function correlates with protection following vaccination.
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Affiliation(s)
- Mr Olson
- Department of Microbiology & Immunology, University of Melbourne, Parkville, VIC, 3010, Australia
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25
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Abstract
Evaluation of cell-mediated immunity (CMI) is a significant component in any assessment designed to predict the full range of potential immunotoxic risk underlying health risks. Among measures of CMI, the cytotoxic T Lymphocyte (CTL) response is recognized as perhaps the most relevant functional measure that reflects cell-mediated acquired immune defense against viral infections and cancer. The CTL response against T-dependent antigens requires the cooperation of at least three different major categories of immune cells. These include professional antigen presenting cells (e.g., dendritic cells), CD4(+) T helper lymphocytes, and CD8(+) T effector lymphocytes. It is also among the few functional responses dependent on and, hence, capable of evaluating effective antigen presentation via both class I and class II molecules of the major histocompatibility complex (MHC). For this reason the CTL assay is an excellent candidate for evaluation of potential immunotoxicity. This chapter provides an example of a mouse CTL assay against influenza virus that has been utilized for this purpose.
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26
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Hoves S, Trapani JA, Voskoboinik I. The battlefield of perforin/granzyme cell death pathways. J Leukoc Biol 2009; 87:237-43. [DOI: 10.1189/jlb.0909608] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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27
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Moffat JM, Gebhardt T, Doherty PC, Turner SJ, Mintern JD. Granzyme A expression reveals distinct cytolytic CTL subsets following influenza A virus infection. Eur J Immunol 2009; 39:1203-10. [PMID: 19404988 DOI: 10.1002/eji.200839183] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
CTL mediate anti-viral immunity via targeted exocytosis of cytolytic granules containing perforin and members of the granzyme (grz) serine protease family. Here, we provide the first analysis of grzA protein expression by murine anti-viral CTL. During the progression of influenza A virus infection, CTL expressed two divergent cytolytic phenotypes: grzA(-)B(+) and grzA(+)B(+). CTL lacked grzA expression during the initial rounds of antigen-driven division. High levels of grzA were expressed by influenza-specific CTL early post infection (day 6), particularly in tissues associated with the infected respiratory tract (bronchoalveolar lavage, lung). Following resolution of influenza infection, a small population of memory CTL expressed grzA. Interestingly, individual influenza A virus-derived epitope-specific CTL expressed different levels of grzA. The grzA expression hierarchy was determined to be K(b)PB1(703)=D(b)F2(62)=K(b)NS2(114)>D(b)NP(366)=D(b)PA(224) and inversely correlated with CTL magnitude. Therefore following influenza infection, a CTL cytolytic hierarchy was established relating to the different profiles of antigen expression and relative immunodominance. Analysis of CTL grzA expression during influenza virus immunity has enabled a more detailed insight into the cytolytic mechanisms of virus elimination.
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Affiliation(s)
- Jessica M Moffat
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria, Australia
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28
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The biology of cytotoxic cell granule exocytosis pathway: granzymes have evolved to induce cell death and inflammation. Microbes Infect 2009; 11:452-9. [DOI: 10.1016/j.micinf.2009.02.004] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2009] [Accepted: 02/13/2009] [Indexed: 11/21/2022]
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29
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Jenkins MR, La Gruta NL, Doherty PC, Trapani JA, Turner SJ, Waterhouse NJ. Visualizing CTL activity for different CD8+ effector T cells supports the idea that lower TCR/epitope avidity may be advantageous for target cell killing. Cell Death Differ 2009; 16:537-42. [PMID: 19136939 DOI: 10.1038/cdd.2008.176] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Time-lapse video microscopy allows analysis of the interaction between individual CTLs and adherent peptide-pulsed targets, from contact, to lymphocyte detachment, APC rounding, phosphatidylserine exposure and finally loss of plasma membrane integrity characteristic of end-stage apoptosis. Using in vitro-stimulated effectors specific for the ovalbumin K(b)OVA(257) (OT-I) and influenza A virus D(b)NP(366) and D(b)PA(224) epitopes, no significant correlation was found between the duration of CTL contact and the time to phosphatidylserine exposure or loss of membrane integrity. Furthermore, there were minimal indications that transgenic T cells specific for the K(b)OVA(257) epitope (TCR) diversity had any effect. However, when the analysis was repeated with D(b)NP(366) and D(b)PA(224)-specific CTLs recovered directly from the lungs of mice with influenza pneumonia, the lower avidity D(b)NP(366)-specific set was found to elute much more quickly. Shorter contact time may allow individual CTLs to lyse more targets, suggesting that lower TCR/epitope avidity may be more beneficial than higher epitope avidity for cell-mediated immunity.
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Affiliation(s)
- M R Jenkins
- Department of Microbiology and Immunology, The University of Melbourne, Parkville, Victoria 3010, Australia
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