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Li Y, Xiao J, Li C, Yang M. Memory inflation: Beyond the acute phase of viral infection. Cell Prolif 2024:e13705. [PMID: 38992867 DOI: 10.1111/cpr.13705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/09/2024] [Accepted: 06/14/2024] [Indexed: 07/13/2024] Open
Abstract
Memory inflation is confirmed as the most commonly dysregulation of host immunity with antigen-independent manner in mammals after viral infection. By generating large numbers of effector/memory and terminal differentiated effector memory CD8+ T cells with diminished naïve subsets, memory inflation is believed to play critical roles in connecting the viral infection and the onset of multiple diseases. Here, we reviewed the current understanding of memory inflated CD8+ T cells in their distinct phenotypic features that different from exhausted subsets; the intrinsic and extrinsic roles in regulating the formation of memory inflation; and the key proteins in maintaining the expansion and proliferation of inflationary populations. More importantly, based on the evidences from both clinic and animal models, we summarized the potential mechanisms of memory inflation to trigger autoimmune neuropathies, such as Guillain-Barré syndrome and multiple sclerosis; the correlations of memory inflation between tumorigenesis and resistance of tumour immunotherapies; as well as the effects of memory inflation to facilitate vascular disease progression. To sum up, better understanding of memory inflation could provide us an opportunity to beyond the acute phase of viral infection, and shed a light on the long-term influences of CD8+ T cell heterogeneity in dampen host immune homeostasis.
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Affiliation(s)
- Yanfei Li
- School of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, China
| | - Jie Xiao
- Centre for Translational Research in Cancer, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Chen Li
- Centre for Translational Research in Cancer, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
| | - Mu Yang
- School of Basic Medical Sciences, Chengdu University of Traditional Chinese Medicine, Chengdu, China
- Centre for Translational Research in Cancer, Sichuan Cancer Hospital and Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu, China
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2
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Holtappels R, Büttner JK, Freitag K, Reddehase MJ, Lemmermann NA. Modulation of cytomegalovirus immune evasion identifies direct antigen presentation as the predominant mode of CD8 T-cell priming during immune reconstitution after hematopoietic cell transplantation. Front Immunol 2024; 15:1355153. [PMID: 38426094 PMCID: PMC10902149 DOI: 10.3389/fimmu.2024.1355153] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Accepted: 02/01/2024] [Indexed: 03/02/2024] Open
Abstract
Cytomegalovirus (CMV) infection is the most critical infectious complication in recipients of hematopoietic cell transplantation (HCT) in the period between a therapeutic hematoablative treatment and the hematopoietic reconstitution of the immune system. Clinical investigation as well as the mouse model of experimental HCT have consistently shown that timely reconstitution of antiviral CD8 T cells is critical for preventing CMV disease in HCT recipients. Reconstitution of cells of the T-cell lineage generates naïve CD8 T cells with random specificities among which CMV-specific cells need to be primed by presentation of viral antigen for antigen-specific clonal expansion and generation of protective antiviral effector CD8 T cells. For CD8 T-cell priming two pathways are discussed: "direct antigen presentation" by infected professional antigen-presenting cells (pAPCs) and "antigen cross-presentation" by uninfected pAPCs that take up antigenic material derived from infected tissue cells. Current view in CMV immunology favors the cross-priming hypothesis with the argument that viral immune evasion proteins, known to interfere with the MHC class-I pathway of direct antigen presentation by infected cells, would inhibit the CD8 T-cell response. While the mode of antigen presentation in the mouse model of CMV infection has been studied in the immunocompetent host under genetic or experimental conditions excluding either pathway of antigen presentation, we are not aware of any study addressing the medically relevant question of how newly generated naïve CD8 T cells become primed in the phase of lympho-hematopoietic reconstitution after HCT. Here we used the well-established mouse model of experimental HCT and infection with murine CMV (mCMV) and pursued the recently described approach of up- or down-modulating direct antigen presentation by using recombinant viruses lacking or overexpressing the central immune evasion protein m152 of mCMV, respectively. Our data reveal that the magnitude of the CD8 T-cell response directly reflects the level of direct antigen presentation.
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Affiliation(s)
- Rafaela Holtappels
- Institute for Virology and Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Julia K. Büttner
- Institute for Virology and Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Kirsten Freitag
- Institute for Virology and Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Matthias J. Reddehase
- Institute for Virology and Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
| | - Niels A. Lemmermann
- Institute for Virology and Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg University Mainz, Mainz, Germany
- Institute of Virology, Medical Faculty, University of Bonn, Bonn, Germany
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3
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Holtappels R, Becker S, Hamdan S, Freitag K, Podlech J, Lemmermann NA, Reddehase MJ. Immunotherapy of cytomegalovirus infection by low-dose adoptive transfer of antiviral CD8 T cells relies on substantial post-transfer expansion of central memory cells but not effector-memory cells. PLoS Pathog 2023; 19:e1011643. [PMID: 37972198 PMCID: PMC10688903 DOI: 10.1371/journal.ppat.1011643] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 11/30/2023] [Accepted: 11/06/2023] [Indexed: 11/19/2023] Open
Abstract
Cytomegaloviruses (CMVs) are host species-specific in their replication. It is a hallmark of all CMVs that productive primary infection is controlled by concerted innate and adaptive immune responses in the immunocompetent host. As a result, the infection usually passes without overt clinical symptoms and develops into latent infection, referred to as "latency". During latency, the virus is maintained in a non-replicative state from which it can reactivate to productive infection under conditions of waning immune surveillance. In contrast, infection of an immunocompromised host causes CMV disease with viral multiple-organ histopathology resulting in organ failure. Primary or reactivated CMV infection of hematopoietic cell transplantation (HCT) recipients in a "window of risk" between therapeutic hemato-ablative leukemia therapy and immune system reconstitution remains a clinical challenge. Studies in the mouse model of experimental HCT and infection with murine CMV (mCMV), followed by clinical trials in HCT patients with human CMV (hCMV) reactivation, have revealed a protective function of virus-specific CD8 T cells upon adoptive cell transfer (AT). Memory CD8 T cells derived from latently infected hosts are a favored source for immunotherapy by AT. Strikingly low numbers of these cells were found to prevent CMV disease, suggesting either an immediate effector function of few transferred cells or a clonal expansion generating high numbers of effector cells. In the murine model, the memory population consists of resting central memory T cells (TCM), as well as of conventional effector-memory T cells (cTEM) and inflationary effector-memory T cells (iTEM). iTEM increase in numbers over time in the latently infected host, a phenomenon known as 'memory inflation' (MI). They thus appeared to be a promising source for use in immunotherapy. However, we show here that iTEM contribute little to the control of infection after AT, which relies almost entirely on superior proliferative potential of TCM.
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Affiliation(s)
- Rafaela Holtappels
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Sara Becker
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Institute of Virology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Sara Hamdan
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Kirsten Freitag
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Jürgen Podlech
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Niels A. Lemmermann
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Institute of Virology, Medical Faculty, University of Bonn, Bonn, Germany
| | - Matthias J. Reddehase
- Institute for Virology, University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
- Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University Mainz, Mainz, Germany
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4
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Yu P, Lian Y, Zuleger CL, Albertini RJ, Albertini MR, Newton MA. SURROGATE SELECTION OVERSAMPLES EXPANDED T CELL CLONOTYPES. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.13.548950. [PMID: 37503118 PMCID: PMC10369934 DOI: 10.1101/2023.07.13.548950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Inference from immunological data on cells in the adaptive immune system may benefit from modeling specifications that describe variation in the sizes of various clonal sub-populations. We develop one such specification in order to quantify the effects of surrogate selection assays, which we confirm may lead to an enrichment for amplified, potentially disease-relevant T cell clones. Our specification couples within-clonotype birth-death processes with an exchangeable model across clonotypes. Beyond enrichment questions about the surrogate selection design, our framework enables a study of sampling properties of elementary sample diversity statistics; it also points to new statistics that may usefully measure the burden of somatic genomic alterations associated with clonal expansion. We examine statistical properties of immunological samples governed by the coupled model specification, and we illustrate calculations in surrogate selection studies of melanoma and in single-cell genomic studies of T cell repertoires.
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Affiliation(s)
- Peng Yu
- Department of Statistics, University of Wisconsin, Madison
| | - Yumin Lian
- Department of Chemistry, Laboratory of Genetics, University of Wisconsin, Madison
| | - Cindy L. Zuleger
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin, Madison
- Carbone Cancer Center, University of Wisconsin, Madison
| | | | - Mark R. Albertini
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin, Madison
- Carbone Cancer Center, University of Wisconsin, Madison
- Medical Service, William S. Middleton Memorial Veterans Hospital, Madison
| | - Michael A. Newton
- Department of Statistics, University of Wisconsin, Madison
- Carbone Cancer Center, University of Wisconsin, Madison
- Department of Biostatistics and Medical Informatics, University of Wisconsin, Madison
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5
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De Boer RJ, Yates AJ. Modeling T Cell Fate. Annu Rev Immunol 2023; 41:513-532. [PMID: 37126420 PMCID: PMC11100019 DOI: 10.1146/annurev-immunol-101721-040924] [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] [Indexed: 05/02/2023]
Abstract
Many of the pathways that underlie the diversification of naive T cells into effector and memory subsets, and the maintenance of these populations, remain controversial. In recent years a variety of experimental tools have been developed that allow us to follow the fates of cells and their descendants. In this review we describe how mathematical models provide a natural language for describing the growth, loss, and differentiation of cell populations. By encoding mechanistic descriptions of cell behavior, models can help us interpret these new datasets and reveal the rules underpinning T cell fate decisions, both at steady state and during immune responses.
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Affiliation(s)
- Rob J De Boer
- Theoretical Biology and Bioinformatics, Department of Biology, Utrecht University, Utrecht, The Netherlands;
| | - Andrew J Yates
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA;
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6
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Bonavita CM, White TM, Francis J, Farrell HE, Davis-Poynter NJ, Cardin RD. The Viral G-Protein-Coupled Receptor Homologs M33 and US28 Promote Cardiac Dysfunction during Murine Cytomegalovirus Infection. Viruses 2023; 15:711. [PMID: 36992420 PMCID: PMC10054303 DOI: 10.3390/v15030711] [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: 12/29/2022] [Revised: 03/06/2023] [Accepted: 03/07/2023] [Indexed: 03/12/2023] Open
Abstract
Human cytomegalovirus (HCMV) is a ubiquitous pathogen that infects the majority of the world population and causes lifelong latent infection. HCMV has been shown to exacerbate cardiovascular diseases, including myocarditis, vascular sclerosis, and transplant vasculopathy. Recently, we have shown that murine CMV (MCMV) recapitulates the cardiovascular dysfunction observed in patients with HCMV-induced myocarditis. To understand the viral mechanisms involved in CMV-induced heart dysfunction, we further characterized cardiac function in response to MCMV and examined virally encoded G-protein-coupled receptor homologs (vGPCRs) US28 and M33 as potential factors that promote infection in the heart. We hypothesized that the CMV-encoded vGPCRs could exacerbate cardiovascular damage and dysfunction. Three viruses were used to evaluate the role of vGPCRs in cardiac dysfunction: wild-type MCMV, a M33-deficient virus (∆M33), and a virus with the M33 open reading frame (ORF) replaced with US28, an HCMV vGPCR (i.e., US28+). Our in vivo studies revealed that M33 plays a role in promoting cardiac dysfunction by increasing viral load and heart rate during acute infection. During latency, ΔM33-infected mice demonstrated reduced calcification, altered cellular gene expression, and less cardiac hypertrophy compared with wild-type MCMV-infected mice. Ex vivo viral reactivation from hearts was less efficient in ΔM33-infected animals. HCMV protein US28 expression restored the ability of the M33-deficient virus to reactivate from the heart. US28+ MCMV infection caused damage to the heart comparable with wild-type MCMV infection, suggesting that the US28 protein is sufficient to complement the function of M33 in the heart. Altogether, these data suggest a role for vGPCRs in viral pathogenesis in the heart and thus suggest that vGPCRs promote long-term cardiac damage and dysfunction.
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Affiliation(s)
- Cassandra M. Bonavita
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Timothy M. White
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Joseph Francis
- Department of Comparative Biological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
| | - Helen E. Farrell
- School of Chemistry and Molecular Bioscience, University of Queensland, Brisbane 4072, Australia
| | | | - Rhonda D. Cardin
- Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA
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7
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Zangger N, Oxenius A. T cell immunity to cytomegalovirus infection. Curr Opin Immunol 2022; 77:102185. [DOI: 10.1016/j.coi.2022.102185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/07/2022] [Indexed: 11/17/2022]
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8
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Baliu-Piqué M, Drylewicz J, Zheng X, Borkner L, Swain AC, Otto SA, de Boer RJ, Tesselaar K, Cicin-Sain L, Borghans JAM. Turnover of Murine Cytomegalovirus-Expanded CD8 + T Cells Is Similar to That of Memory Phenotype T Cells and Independent of the Magnitude of the Response. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:799-806. [PMID: 35091435 DOI: 10.4049/jimmunol.2100883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 12/08/2021] [Indexed: 11/19/2022]
Abstract
The potential of memory T cells to provide protection against reinfection is beyond question. Yet, it remains debated whether long-term T cell memory is due to long-lived memory cells. There is ample evidence that blood-derived memory phenotype CD8+ T cells maintain themselves through cell division, rather than through longevity of individual cells. It has recently been proposed, however, that there may be heterogeneity in the lifespans of memory T cells, depending on factors such as exposure to cognate Ag. CMV infection induces not only conventional, contracting T cell responses, but also inflationary CD8+ T cell responses, which are maintained at unusually high numbers, and are even thought to continue to expand over time. It has been proposed that such inflating T cell responses result from the accumulation of relatively long-lived CMV-specific memory CD8+ T cells. Using in vivo deuterium labeling and mathematical modeling, we found that the average production rates and expected lifespans of mouse CMV-specific CD8+ T cells are very similar to those of bulk memory-phenotype CD8+ T cells. Even CMV-specific inflationary CD8+ T cell responses that differ 3-fold in size were found to turn over at similar rates.
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Affiliation(s)
- Mariona Baliu-Piqué
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Julia Drylewicz
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Xiaoyan Zheng
- Department of Viral Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Lisa Borkner
- Department of Viral Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Arpit C Swain
- Theoretical Biology, Utrecht University, Utrecht, The Netherlands; and
| | - Sigrid A Otto
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Rob J de Boer
- Theoretical Biology, Utrecht University, Utrecht, The Netherlands; and
| | - Kiki Tesselaar
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Luka Cicin-Sain
- Department of Viral Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany.,German Center for Infection Research, Partner Site, Hannover-Braunschweig, Germany
| | - José A M Borghans
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, the Netherlands;
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9
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Higdon LE, Schaffert S, Huang H, Montez-Rath ME, Lucia M, Jha A, Saligrama N, Margulies KB, Martinez OM, Davis MM, Khatri P, Maltzman JS. Evolution of Cytomegalovirus-Responsive T Cell Clonality following Solid Organ Transplantation. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2021; 207:2077-2085. [PMID: 34551964 PMCID: PMC8492537 DOI: 10.4049/jimmunol.2100404] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 08/04/2021] [Indexed: 12/30/2022]
Abstract
CMV infection is a significant complication after solid organ transplantation. We used single cell TCR αβ sequencing to determine how memory inflation impacts clonality and diversity of the CMV-responsive CD8 and CD4 T cell repertoire in the first year after transplantation in human subjects. We observed CD8 T cell inflation but no changes in clonal diversity, indicating homeostatic stability in clones. In contrast, the CD4 repertoire was diverse and stable over time, with no evidence of CMV-responsive CD4 T cell expansion. We identified shared CDR3 TCR motifs among patients but no public CMV-specific TCRs. Temporal changes in clonality in response to transplantation and in the absence of detectable viral reactivation suggest changes in the repertoire immediately after transplantation followed by an expansion with stable clonal competition that may mediate protection.
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Affiliation(s)
- Lauren E Higdon
- Nephrology Division, Department of Medicine, Stanford University, Palo Alto, CA
| | - Steven Schaffert
- Institute for Immunity, Transplantation and Infection, Stanford University, Stanford, CA
- Biomedical Informatics Division, Department of Medicine, Stanford University, Stanford, CA
| | - Huang Huang
- Department of Microbiology and Immunology, Stanford University, Stanford CA
| | - Maria E Montez-Rath
- Nephrology Division, Department of Medicine, Stanford University, Palo Alto, CA
| | - Marc Lucia
- Department of Surgery, Stanford University, Stanford, CA
| | - Alokkumar Jha
- Cardiovascular Institute, Stanford University, Stanford, CA
| | - Naresha Saligrama
- Department of Microbiology and Immunology, Stanford University, Stanford CA
| | - Kenneth B Margulies
- Cardiovascular Institute, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA
| | | | - Mark M Davis
- Institute for Immunity, Transplantation and Infection, Stanford University, Stanford, CA
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford University, Stanford, CA; and
| | - Purvesh Khatri
- Institute for Immunity, Transplantation and Infection, Stanford University, Stanford, CA
- Biomedical Informatics Division, Department of Medicine, Stanford University, Stanford, CA
| | - Jonathan S Maltzman
- Nephrology Division, Department of Medicine, Stanford University, Palo Alto, CA;
- Veterans Affairs Palo Alto Health Care System, Palo Alto, CA
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10
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Blaum F, Lukas D, Reddehase MJ, Lemmermann NAW. Localization of Viral Epitope-Specific CD8 T Cells during Cytomegalovirus Latency in the Lungs and Recruitment to Lung Parenchyma by Airway Challenge Infection. Life (Basel) 2021; 11:life11090918. [PMID: 34575067 PMCID: PMC8467276 DOI: 10.3390/life11090918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/01/2021] [Accepted: 09/02/2021] [Indexed: 01/10/2023] Open
Abstract
Interstitial pneumonia is a life-threatening clinical manifestation of cytomegalovirus infection in recipients of hematopoietic cell transplantation (HCT). The mouse model of experimental HCT and infection with murine cytomegalovirus revealed that reconstitution of virus-specific CD8+ T cells is critical for resolving productive lung infection. CD8+ T-cell infiltrates persisted in the lungs after the establishment of latent infection. A subset defined by the phenotype KLRG1+CD62L− expanded over time, a phenomenon known as memory inflation (MI). Here we studied the localization of these inflationary T effector-memory cells (iTEM) by comparing their frequencies in the intravascular and transmigration compartments, the IVC and TMC, respectively, with their frequency in the extravascular compartment (EVC), the alveolar epithelium. Frequencies of viral epitope-specific iTEM were comparable in the IVC and TMC but were reduced in the EVC, corresponding to an increase in KLRG1−CD62L− conventional T effector-memory cells (cTEM) and a decrease in functional IFNγ+CD8+ T cells. As maintained expression of KLRG1 requires stimulation by antigen, we conclude that iTEM lose KLRG1 and convert to cTEM after transmigration into the EVC because pneumocytes are not latently infected and, therefore, do not express antigens. Accordingly, antigen re-expression upon airway challenge infection recruited virus-specific CD8+ T cells to TMC and EVC.
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Affiliation(s)
- Franziska Blaum
- Institute for Virology, Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (F.B.); (N.A.W.L.)
| | - Dominika Lukas
- Department of Dermatology, University of Cologne, University Hospital Cologne and Faculty of Medicine, 50937 Cologne, Germany;
| | - Matthias J. Reddehase
- Institute for Virology, Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (F.B.); (N.A.W.L.)
- Correspondence:
| | - Niels A. W. Lemmermann
- Institute for Virology, Research Center for Immunotherapy (FZI), University Medical Center of the Johannes Gutenberg-University Mainz, 55131 Mainz, Germany; (F.B.); (N.A.W.L.)
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11
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Immunodominant Cytomegalovirus Epitopes Suppress Subdominant Epitopes in the Generation of High-Avidity CD8 T Cells. Pathogens 2021; 10:pathogens10080956. [PMID: 34451420 PMCID: PMC8400798 DOI: 10.3390/pathogens10080956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2021] [Revised: 07/19/2021] [Accepted: 07/24/2021] [Indexed: 01/04/2023] Open
Abstract
CD8+ T-cell responses to pathogens are directed against infected cells that present pathogen-encoded peptides on MHC class-I molecules. Although natural responses are polyclonal, the spectrum of peptides that qualify for epitopes is remarkably small even for pathogens with high coding capacity. Among those few that are successful at all, a hierarchy exists in the magnitude of the response that they elicit in terms of numbers of CD8+ T cells generated. This led to a classification into immunodominant and non-immunodominant or subordinate epitopes, IDEs and non-IDEs, respectively. IDEs are favored in the design of vaccines and are chosen for CD8+ T-cell immunotherapy. Using murine cytomegalovirus as a model, we provide evidence to conclude that epitope hierarchy reflects competition on the level of antigen recognition. Notably, high-avidity cells specific for non-IDEs were found to expand only when IDEs were deleted. This may be a host’s back-up strategy to avoid viral immune escape through antigenic drift caused by IDE mutations. Importantly, our results are relevant for the design of vaccines based on cytomegaloviruses as vectors to generate high-avidity CD8+ T-cell memory specific for unrelated pathogens or tumors. We propose the deletion of vector-encoded IDEs to avoid the suppression of epitopes of the vaccine target.
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12
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Direct Evidence for Viral Antigen Presentation during Latent Cytomegalovirus Infection. Pathogens 2021; 10:pathogens10060731. [PMID: 34200578 PMCID: PMC8229173 DOI: 10.3390/pathogens10060731] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Revised: 06/05/2021] [Accepted: 06/08/2021] [Indexed: 02/07/2023] Open
Abstract
Murine models of cytomegalovirus (CMV) infection have revealed an immunological phenomenon known as “memory inflation” (MI). After a peak of a primary CD8+ T-cell response, the pool of epitope-specific cells contracts in parallel to the resolution of productive infection and the establishment of a latent infection, referred to as “latency.” CMV latency is associated with an increase in the number of cells specific for certain viral epitopes over time. The inflationary subset was identified as effector-memory T cells (iTEM) characterized by the cell surface phenotype KLRG1+CD127−CD62L−. As we have shown recently, latent viral genomes are not transcriptionally silent. Rather, viral genes are sporadically desilenced in a stochastic fashion. The current hypothesis proposes MI to be driven by presented viral antigenic peptides encoded by the corresponding, stochastically expressed viral genes. Although this mechanism suggests itself, independent evidence for antigen presentation during viral latency is pending. Here we fill this gap by showing that T cell-receptor transgenic OT-I cells that are specific for peptide SIINFEKL proliferate upon adoptive cell transfer in C57BL/6 recipients latently infected with murine CMV encoding SIINFEKL (mCMV-SIINFEKL), but not in those latently infected with mCMV-SIINFEKA, in which antigenicity is lost by mutation L8A of the C-terminal amino acid residue.
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13
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Lanfermeijer J, de Greef PC, Hendriks M, Vos M, van Beek J, Borghans JAM, van Baarle D. Age and CMV-Infection Jointly Affect the EBV-Specific CD8 + T-Cell Repertoire. FRONTIERS IN AGING 2021; 2:665637. [PMID: 35822032 PMCID: PMC9261403 DOI: 10.3389/fragi.2021.665637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 03/31/2021] [Indexed: 01/15/2023]
Abstract
CD8+ T cells play an important role in protection against viral infections. With age, changes in the T-cell pool occur, leading to diminished responses against both new and recurring infections in older adults. This is thought to be due to a decrease in both T-cell numbers and T-cell receptor (TCR) diversity. Latent infection with cytomegalovirus (CMV) is assumed to contribute to this age-associated decline of the immune system. The observation that the level of TCR diversity in the total memory T-cell pool stays relatively stable during aging is remarkable in light of the constant input of new antigen-specific memory T cells. What happens with the diversity of the individual antigen-specific T-cell repertoires in the memory pool remains largely unknown. Here we studied the effect of aging on the phenotype and repertoire diversity of CMV-specific and Epstein-Barr virus (EBV)-specific CD8+ T cells, as well as the separate effects of aging and CMV-infection on the EBV-specific T-cell repertoire. Antigen-specific T cells against both persistent viruses showed an age-related increase in the expression of markers associated with a more differentiated phenotype, including KLRG-1, an increase in the fraction of terminally differentiated T cells, and a decrease in the diversity of the T-cell repertoire. Not only age, but also CMV infection was associated with a decreased diversity of the EBV-specific T-cell repertoire. This suggests that both CMV infection and age can impact the T-cell repertoire against other antigens.
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Affiliation(s)
- Josien Lanfermeijer
- Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, Netherlands
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Peter C. de Greef
- Theoretical Biology and Bioinformatics, Utrecht University, Utrecht, Netherlands
| | - Marion Hendriks
- Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | - Martijn Vos
- Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | - Josine van Beek
- Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, Netherlands
| | - José A. M. Borghans
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
| | - Debbie van Baarle
- Center for Infectious Disease Control, National Institute for Public Health and the Environment, Bilthoven, Netherlands
- Center for Translational Immunology, University Medical Center Utrecht, Utrecht, Netherlands
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14
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Griessl M, Renzaho A, Freitag K, Seckert CK, Reddehase MJ, Lemmermann NAW. Stochastic Episodes of Latent Cytomegalovirus Transcription Drive CD8 T-Cell "Memory Inflation" and Avoid Immune Evasion. Front Immunol 2021; 12:668885. [PMID: 33968074 PMCID: PMC8100209 DOI: 10.3389/fimmu.2021.668885] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 04/06/2021] [Indexed: 11/29/2022] Open
Abstract
Acute infection with murine cytomegalovirus (mCMV) is controlled by CD8+ T cells and develops into a state of latent infection, referred to as latency, which is defined by lifelong maintenance of viral genomes but absence of infectious virus in latently infected cell types. Latency is associated with an increase in numbers of viral epitope-specific CD8+ T cells over time, a phenomenon known as "memory inflation" (MI). The "inflationary" subset of CD8+ T cells has been phenotyped as KLRG1+CD62L- effector-memory T cells (iTEM). It is agreed upon that proliferation of iTEM requires repeated episodes of antigen presentation, which implies that antigen-encoding viral genes must be transcribed during latency. Evidence for this has been provided previously for the genes encoding the MI-driving antigenic peptides IE1-YPHFMPTNL and m164-AGPPRYSRI of mCMV in the H-2d haplotype. There exist two competing hypotheses for explaining MI-driving viral transcription. The "reactivation hypothesis" proposes frequent events of productive virus reactivation from latency. Reactivation involves a coordinated gene expression cascade from immediate-early (IE) to early (E) and late phase (L) transcripts, eventually leading to assembly and release of infectious virus. In contrast, the "stochastic transcription hypothesis" proposes that viral genes become transiently de-silenced in latent viral genomes in a stochastic fashion, not following the canonical IE-E-L temporal cascade of reactivation. The reactivation hypothesis, however, is incompatible with the finding that productive virus reactivation is exceedingly rare in immunocompetent mice and observed only under conditions of compromised immunity. In addition, the reactivation hypothesis fails to explain why immune evasion genes, which are regularly expressed during reactivation in the same cells in which epitope-encoding genes are expressed, do not prevent antigen presentation and thus MI. Here we show that IE, E, and L genes are transcribed during latency, though stochastically, not following the IE-E-L temporal cascade. Importantly, transcripts that encode MI-driving antigenic peptides rarely coincide with those that encode immune evasion proteins. As immune evasion can operate only in cis, that is, in a cell that simultaneously expresses antigenic peptides, the stochastic transcription hypothesis explains why immune evasion is not operative in latently infected cells and, therefore, does not interfere with MI.
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Affiliation(s)
| | | | | | | | | | - Niels A. W. Lemmermann
- Institute for Virology, Research Center for Immunotherapy (FZI) at the University Medical Center of the Johannes Gutenberg-University of Mainz, Mainz, Germany
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15
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Parry HM, Dowell AC, Zuo J, Verma K, Kinsella FAM, Begum J, Croft W, Sharma-Oates A, Pratt G, Moss P. PD-1 is imprinted on cytomegalovirus-specific CD4+ T cells and attenuates Th1 cytokine production whilst maintaining cytotoxicity. PLoS Pathog 2021; 17:e1009349. [PMID: 33662046 PMCID: PMC7963093 DOI: 10.1371/journal.ppat.1009349] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2020] [Revised: 03/16/2021] [Accepted: 02/01/2021] [Indexed: 12/12/2022] Open
Abstract
PD-1 is expressed on exhausted T cells in cancer patients but its physiological role remains uncertain. We determined the phenotype, function and transcriptional correlates of PD-1 expression on cytomegalovirus-specific CD4+ T cells during latent infection. PD-1 expression ranged from 10-85% and remained stable over time within individual donors. This 'setpoint' was correlated with viral load at primary infection. PD-1+ CD4+ T cells display strong cytotoxic function but generate low levels of Th1 cytokines which is only partially reversed by PD-1 blockade. TCR clonotypes showed variable sharing between PD-1+ and PD-1- CMV-specific cells indicating that PD-1 status is defined either during T cell priming or subsequent clonal expansion. Physiological PD-1+ CD4+ T cells therefore display a unique 'high cytotoxicity-low cytokine' phenotype and may act to suppress viral reactivation whilst minimizing tissue inflammation. Improved understanding of the physiological role of PD-1 will help to delineate the mechanisms, and potential reversal, of PD-1+ CD4+ T cell exhaustion in patients with malignant disease.
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Affiliation(s)
- Helen M. Parry
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Alexander C. Dowell
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jianmin Zuo
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Kriti Verma
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Francesca A. M. Kinsella
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Jusnara Begum
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Wayne Croft
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Centre for Computational Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Archana Sharma-Oates
- Centre for Computational Biology, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Institute of Cancer & Genomics, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
| | - Guy Pratt
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
- Queen Elizabeth Hospital, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom
| | - Paul Moss
- Institute of Immunology & Immunotherapy, College of Medical and Dental Sciences, University of Birmingham, Birmingham, United Kingdom
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16
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Lanfermeijer J, Borghans JAM, Baarle D. How age and infection history shape the antigen-specific CD8 + T-cell repertoire: Implications for vaccination strategies in older adults. Aging Cell 2020; 19:e13262. [PMID: 33078890 PMCID: PMC7681067 DOI: 10.1111/acel.13262] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 09/21/2020] [Accepted: 09/25/2020] [Indexed: 12/21/2022] Open
Abstract
Older adults often show signs of impaired CD8+ T‐cell immunity, reflected by weaker responses against new infections and vaccinations, and decreased protection against reinfection. This immune impairment is in part thought to be the consequence of a decrease in both T‐cell numbers and repertoire diversity. If this is indeed the case, a strategy to prevent infectious diseases in older adults could be the induction of protective memory responses through vaccination at a younger age. However, this requires that the induced immune responses are maintained until old age. It is therefore important to obtain insights into the long‐term maintenance of the antigen‐specific T‐cell repertoire. Here, we review the literature on the maintenance of antigen‐experienced CD8+ T‐cell repertoires against acute and chronic infections. We describe the complex interactions that play a role in shaping the memory T‐cell repertoire, and the effects of age, infection history, and T‐cell avidity. We discuss the implications of these findings for the development of new vaccination strategies to protect older adults.
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Affiliation(s)
- Josien Lanfermeijer
- Center for Infectious Disease Control National Institute for Public Health and the Environment Bilthoven the Netherlands
- Center for Translational Immunology University Medical Center Utrecht the Netherlands
| | - José A. M. Borghans
- Center for Translational Immunology University Medical Center Utrecht the Netherlands
| | - Debbie Baarle
- Center for Infectious Disease Control National Institute for Public Health and the Environment Bilthoven the Netherlands
- Center for Translational Immunology University Medical Center Utrecht the Netherlands
- Virology & Immunology Research Department of Medical Microbiology and Infection prevention University Medical Center Groningen the Netherlands
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17
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Abassi L, Cicin-Sain L. The avid competitors of memory inflation. Curr Opin Virol 2020; 44:162-168. [PMID: 33039898 DOI: 10.1016/j.coviro.2020.08.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Revised: 08/14/2020] [Accepted: 08/16/2020] [Indexed: 12/18/2022]
Abstract
Cytomegaloviruses (CMV) coevolve with their hosts and latently persist in the vast majority of adult mammals. Therefore, persistent T-cell responses to CMV antigens during virus latency offer a fascinating perspective on the evolution of the T-cell repertoire in natural settings. We addressed here the life-long interactions between CMV antigens presented on MHC-I molecules and the CD8 T-cell response. We present the mechanistic evidence from the murine model of CMV infection and put it in context of clinical laboratory results. We will highlight the remarkable parallels in T-cell responses between the two biological systems, and focus in particular on memory inflation as a result of competitive processes, both between viral antigenic peptides and between T-cell receptors on the host's cytotoxic lymphocytes.
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Affiliation(s)
- Leila Abassi
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research (HZI), Germany
| | - Luka Cicin-Sain
- Department of Vaccinology and Applied Microbiology, Helmholtz Centre for Infection Research (HZI), Germany; Cluster of Excellence RESIST (EXC 2155), Hannover Medical School (MHH), Germany; Centre for Individualised Infection Medicine (CIIM), A Joint Venture of HZI and MHH, Germany; German Centre for Infection Research (DZIF), Hannover-Braunschweig Site, Germany.
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18
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Schober K, Fuchs P, Mir J, Hammel M, Fanchi L, Flossdorf M, Busch DH. The CMV-Specific CD8 + T Cell Response Is Dominated by Supra-Public Clonotypes with High Generation Probabilities. Pathogens 2020; 9:pathogens9080650. [PMID: 32823573 PMCID: PMC7460440 DOI: 10.3390/pathogens9080650] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/01/2020] [Accepted: 08/11/2020] [Indexed: 12/12/2022] Open
Abstract
Evolutionary processes govern the selection of T cell clonotypes that are optimally suited to mediate efficient antigen-specific immune responses against pathogens and tumors. While the theoretical diversity of T cell receptor (TCR) sequences is vast, the antigen-specific TCR repertoire is restricted by its peptide epitope and the presenting major histocompatibility complex (pMHC). It remains unclear how many TCR sequences are recruited into an antigen-specific T cell response, both within and across different organisms, and which factors shape both of these distributions. Infection of mice with ovalbumin-expressing cytomegalovirus (IE2-OVA-mCMV) represents a well-studied model system to investigate T cell responses given their size and longevity. Here we investigated > 180,000 H2kb/SIINFEKL-recognizing TCR CDR3α or CDR3β sequences from 25 individual mice spanning seven different time points during acute infection and memory inflation. In-depth repertoire analysis revealed that from a pool of highly diverse, but overall limited sequences, T cell responses were dominated by public clonotypes, partly with unexpectedly extreme degrees of sharedness between individual mice ("supra-public clonotypes"). Public clonotypes were found exclusively in a fraction of TCRs with a high generation probability. Generation probability and degree of sharedness select for highly functional TCRs, possibly mediated through elevating intraindividual precursor frequencies of clonotypes.
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Affiliation(s)
- Kilian Schober
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München (TUM), 81675 Munich, Germany; (J.M.); (M.H.); (M.F.)
- German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
- Correspondence: (K.S.); (D.H.B.); Tel.: +49-89-4140-6870 (K.S.); +49-89-4140-4120 (D.H.B.)
| | - Pim Fuchs
- ENPICOM B.V., 5211 AX ‘s-Hertogenbosch, The Netherlands; (P.F.); (L.F.)
| | - Jonas Mir
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München (TUM), 81675 Munich, Germany; (J.M.); (M.H.); (M.F.)
| | - Monika Hammel
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München (TUM), 81675 Munich, Germany; (J.M.); (M.H.); (M.F.)
| | - Lorenzo Fanchi
- ENPICOM B.V., 5211 AX ‘s-Hertogenbosch, The Netherlands; (P.F.); (L.F.)
| | - Michael Flossdorf
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München (TUM), 81675 Munich, Germany; (J.M.); (M.H.); (M.F.)
| | - Dirk H. Busch
- Institute for Medical Microbiology, Immunology and Hygiene, Technische Universität München (TUM), 81675 Munich, Germany; (J.M.); (M.H.); (M.F.)
- German Center for Infection Research (DZIF), partner site Munich, Munich, Germany
- Correspondence: (K.S.); (D.H.B.); Tel.: +49-89-4140-6870 (K.S.); +49-89-4140-4120 (D.H.B.)
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19
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Holtappels R, Freitag K, Renzaho A, Becker S, Lemmermann NA, Reddehase MJ. Revisiting CD8 T-cell 'Memory Inflation': New Insights with Implications for Cytomegaloviruses as Vaccine Vectors. Vaccines (Basel) 2020; 8:vaccines8030402. [PMID: 32707744 PMCID: PMC7563500 DOI: 10.3390/vaccines8030402] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/09/2020] [Accepted: 07/17/2020] [Indexed: 12/12/2022] Open
Abstract
Murine models of cytomegalovirus (CMV) infection have revealed an exceptional kinetics of the immune response. After resolution of productive infection, transient contraction of the viral epitope-specific CD8 T-cell pool was found to be followed by a pool expansion specific for certain viral epitopes during non-productive ‘latent’ infection. This phenomenon, known as ‘memory inflation’ (MI), was found to be based on inflationary KLRG1+CD62L− effector-memory T cells (iTEM) that depend on repetitive restimulation. MI gained substantial interest for employing CMV as vaccine vector by replacing MI-driving CMV epitopes with foreign epitopes for generating high numbers of protective memory cells specific for unrelated pathogens. The concept of an MI-driving CMV vector is questioned by human studies disputing MI in humans. A bias towards MI in experimental models may have resulted from systemic infection. We have here studied local murine CMV infection as a route that is more closely matching routine human vaccine application. Notably, KLRG1−CD62L+ central memory T cells (TCM) and conventional KLRG1−CD62L− effector memory T cells (cTEM) were found to expand, associated with ‘avidity maturation’, whereas the pool size of iTEM steadily declined over time. The establishment of high avidity CD8 T-cell central memory encourages one to pursue the concept of CMV vector-based vaccines.
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