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Waheed W, Bacopulos A, Seyam M, Kooperkamp H, Moin M, Malik T, Tandan R. Physiological and pathological roles of the thymus and value of thymectomy in myasthenia gravis: a narrative review. MEDIASTINUM (HONG KONG, CHINA) 2024; 8:31. [PMID: 38881805 PMCID: PMC11177005 DOI: 10.21037/med-23-43] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 01/15/2024] [Indexed: 06/18/2024]
Abstract
Background and Objective Myasthenia gravis (MG) is a well-elucidated autoimmune disorder affecting the neuromuscular junction. Given the relationship between MG and thymic pathologies, with T cell and antibody-mediated pathogenesis, surgical (i.e., thymectomy) and non-surgical approaches remain a mainstay of management of the disease. This review seeks to outline the involvement of the thymus in the development of lymphocytes leading to MG. Methods Different databases were searched exploring the role of thymectomy in treatment and outcomes in various MG patient subpopulations, including in ocular versus generalized disease, different age groups, and antibody status. Key Content and Findings Overall, the findings of multiple studies and reviews provide evidence to support the efficacy and long-term success of thymectomy in the management of MG; outcomes have included remission status, symptom severity, and need for adjunctive therapy. However, the heterogeneity in the MG population suggests that there are multiple factors that may confound the results of thymectomy and still need further examination. Separately, other autoimmune diseases develop following thymectomy, and further research is required to elucidate this susceptibility. Finally, our review will discuss the different surgical approaches for thymectomy, including their advantages, limitations, and perioperative complications. Conclusions Overall, in light of the known pathogenesis and association of the thymus with MG, thymectomy remains an extremely effective approach for long-term management and improved clinical outcomes.
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Affiliation(s)
- Waqar Waheed
- Department of Neurological Sciences, University of Vermont Robert D. Larner, MD College of Medicine and University of Vermont Medical Center, Burlington, VT, USA
| | - Agnes Bacopulos
- Department of Neurological Sciences, University of Vermont Robert D. Larner, MD College of Medicine and University of Vermont Medical Center, Burlington, VT, USA
| | - Muhannad Seyam
- Department of Neurological Sciences, University of Vermont Robert D. Larner, MD College of Medicine and University of Vermont Medical Center, Burlington, VT, USA
| | - Hannah Kooperkamp
- Division of Thoracic and Cardiac Surgery, University of Vermont Robert D. Larner, MD College of Medicine and University of Vermont Medical Center, Burlington, VT, USA
| | - Maryam Moin
- Department of Neurology, University of Illinois College of Medicine, Peoria, IL, USA
| | - Tariq Malik
- Department of Anesthesiology, Chicago Medical School at Rosalind Franklin University of Medicine and Science, Chicago, IL, USA
| | - Rup Tandan
- Department of Neurological Sciences, University of Vermont Robert D. Larner, MD College of Medicine and University of Vermont Medical Center, Burlington, VT, USA
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2
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Müller L, Di Benedetto S. From aging to long COVID: exploring the convergence of immunosenescence, inflammaging, and autoimmunity. Front Immunol 2023; 14:1298004. [PMID: 37942323 PMCID: PMC10628127 DOI: 10.3389/fimmu.2023.1298004] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 10/12/2023] [Indexed: 11/10/2023] Open
Abstract
The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. This mini-review navigates through the complex landscape of age-associated immune changes, chronic inflammation, age-related autoimmune tendencies, and their potential links with immunopathology of Long COVID. Immunosenescence serves as an introductory departure point, elucidating alterations in immune cell profiles and their functional dynamics, changes in T-cell receptor signaling, cytokine network dysregulation, and compromised regulatory T-cell function. Subsequent scrutiny of chronic inflammation, or "inflammaging," highlights its roles in age-related autoimmune susceptibilities and its potential as a mediator of the immune perturbations observed in Long COVID patients. The introduction of epigenetic facets further amplifies the potential interconnections. In this compact review, we consider the dynamic interactions between immunosenescence, inflammation, and autoimmunity. We aim to explore the multifaceted relationships that link these processes and shed light on the underlying mechanisms that drive their interconnectedness. With a focus on understanding the immunological changes in the context of aging, we seek to provide insights into how immunosenescence and inflammation contribute to the emergence and progression of autoimmune disorders in the elderly and may serve as potential mediator for Long COVID disturbances.
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Affiliation(s)
- Ludmila Müller
- Max Planck Institute for Human Development, Center for Lifespan Psychology, Berlin, Germany
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3
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Lagou MK, Karagiannis GS. Obesity-induced thymic involution and cancer risk. Semin Cancer Biol 2023; 93:3-19. [PMID: 37088128 DOI: 10.1016/j.semcancer.2023.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/19/2023] [Accepted: 04/20/2023] [Indexed: 04/25/2023]
Abstract
Declining thymic functions associated either with old age (i.e., age-related thymic involution), or with acute involution as a result of stress, infectious disease, or cytoreductive therapies (e.g., chemotherapy/radiotherapy), have been associated with cancer development. A key mechanism underlying such increased cancer risk is the thymus-dependent debilitation of adaptive immunity, which is responsible for orchestrating immunoediting mechanisms and tumor immune surveillance. In the past few years, a blooming set of evidence has intriguingly linked obesity with cancer development and progression. The majority of such studies has focused on obesity-driven chronic inflammation, steroid/sex hormone and adipokine production, and hyperinsulinemia, as principal factors affecting the tumor microenvironment and driving the development of primary malignancy. However, experimental observations about the negative impact of obesity on T cell development and maturation have existed for more than half a century. Here, we critically discuss the molecular and cellular mechanisms of obesity-driven thymic involution as a previously underrepresented intermediary pathology leading to cancer development and progression. This knowledge could be especially relevant in the context of childhood obesity, because impaired thymic function in young individuals leads to immune system abnormalities, and predisposes to various pediatric cancers. A thorough understanding behind the molecular and cellular circuitries governing obesity-induced thymic involution could therefore help towards the rationalized development of targeted thymic regeneration strategies for obese individuals at high risk of cancer development.
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Affiliation(s)
- Maria K Lagou
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA; Tumor Microenvironment of Metastasis Program, Albert Einstein Cancer Center, Bronx, NY, USA
| | - George S Karagiannis
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA; Tumor Microenvironment of Metastasis Program, Albert Einstein Cancer Center, Bronx, NY, USA; Cancer Dormancy and Tumor Microenvironment Institute, Albert Einstein College of Medicine, Bronx, NY, USA; Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA; Integrated Imaging Program for Cancer Research, Albert Einstein College of Medicine, Bronx, NY, USA.
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4
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Caruso B, Moran AE. Thymic expression of immune checkpoint molecules and their implication for response to immunotherapies. Trends Cancer 2023:S2405-8033(23)00063-8. [PMID: 37173189 DOI: 10.1016/j.trecan.2023.04.007] [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: 01/20/2023] [Revised: 04/07/2023] [Accepted: 04/14/2023] [Indexed: 05/15/2023]
Abstract
The thymus is responsible for generating a diverse T cell repertoire that is tolerant to self, but capable of responding to various immunologic insults, including cancer. Checkpoint blockade has changed the face of cancer treatment by targeting inhibitory molecules, which are known to regulate peripheral T cell responses. However, these inhibitory molecules and their ligands are expressed during T cell development in the thymus. In this review, we describe the underappreciated role of checkpoint molecule expression during the formation of the T cell repertoire and detail the importance of inhibitory molecules in regulating T cell lineage commitment. Understanding how these molecules function in the thymus may inform therapeutic strategies for better patient outcomes.
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Affiliation(s)
- Breanna Caruso
- Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, OR, USA
| | - Amy E Moran
- Cell, Developmental and Cancer Biology, Oregon Health and Science University, Portland, OR, USA; Knight Cancer Institute, Oregon Health and Science University, Portland, OR, USA.
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5
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Soto-Heredero G, Gómez de Las Heras MM, Escrig-Larena JI, Mittelbrunn M. Extremely Differentiated T Cell Subsets Contribute to Tissue Deterioration During Aging. Annu Rev Immunol 2023; 41:181-205. [PMID: 37126417 DOI: 10.1146/annurev-immunol-101721-064501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
There is a dramatic remodeling of the T cell compartment during aging. The most notorious changes are the reduction of the naive T cell pool and the accumulation of memory-like T cells. Memory-like T cells in older people acquire a phenotype of terminally differentiated cells, lose the expression of costimulatory molecules, and acquire properties of senescent cells. In this review, we focus on the different subsets of age-associated T cells that accumulate during aging. These subsets include extremely cytotoxic T cells with natural killer properties, exhausted T cells with altered cytokine production, and regulatory T cells that gain proinflammatory features. Importantly, all of these subsets lose their lymph node homing capacity and migrate preferentially to nonlymphoid tissues, where they contribute to tissue deterioration and inflammaging.
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Affiliation(s)
- Gonzalo Soto-Heredero
- Homeostasis de Tejidos y Órganos, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC) and Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain;
- Instituto de Investigación Sanitaria del Hospital 12 de Octubre, Madrid, Spain
| | - Manuel M Gómez de Las Heras
- Homeostasis de Tejidos y Órganos, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC) and Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain;
- Instituto de Investigación Sanitaria del Hospital 12 de Octubre, Madrid, Spain
| | - J Ignacio Escrig-Larena
- Homeostasis de Tejidos y Órganos, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC) and Universidad Autónoma de Madrid, Madrid, Spain
- Departamento de Biología Molecular, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain;
| | - María Mittelbrunn
- Homeostasis de Tejidos y Órganos, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas (CSIC) and Universidad Autónoma de Madrid, Madrid, Spain
- Instituto de Investigación Sanitaria del Hospital 12 de Octubre, Madrid, Spain
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6
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Guo L, Li X, Gould T, Wang ZY, Cao W. T cell aging and Alzheimer’s disease. Front Immunol 2023; 14:1154699. [PMID: 37081887 PMCID: PMC10110977 DOI: 10.3389/fimmu.2023.1154699] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/15/2023] [Indexed: 04/07/2023] Open
Abstract
The brain has long been considered an immune-privileged organ due to the presence of the blood-brain barrier (BBB). However, recent discoveries have revealed the underestimated role of T cells in the brain through the meningeal lymphatic system. Age is the primary risk factor for Alzheimer’s disease (AD), resulting in marked age-dependent changes in T cells. Manipulating peripheral T cell immune response has been shown to impact AD, but the relationship between T cell aging and AD remains poorly understood. Given the limited success of targeting amyloid beta (Aβ) and the growing evidence of T cells’ involvement in non-lymphoid organ aging, a deeper understanding of the relationship between T cells and AD in the context of aging is crucial for advancing therapeutic progress. In this review, we comprehensively examine existing studies on T cells and AD and offer an integrated perspective on their interconnections in the context of aging. This understanding can inform the development of new interventions to prevent or treat AD.
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Affiliation(s)
- Lin Guo
- Key Laboratory of Major Chronic Diseases of Nervous System of Liaoning Province, Health Sciences Institute of China Medical University, Shenyang, China
| | - Xiaoting Li
- Key Laboratory of Major Chronic Diseases of Nervous System of Liaoning Province, Health Sciences Institute of China Medical University, Shenyang, China
- Department of Rehabilitation, Shengjing Hospital of China Medical University, Shenyang, China
| | | | - Zhan-You Wang
- Key Laboratory of Major Chronic Diseases of Nervous System of Liaoning Province, Health Sciences Institute of China Medical University, Shenyang, China
- *Correspondence: Wenqiang Cao, ; Zhan-You Wang,
| | - Wenqiang Cao
- Key Laboratory of Major Chronic Diseases of Nervous System of Liaoning Province, Health Sciences Institute of China Medical University, Shenyang, China
- *Correspondence: Wenqiang Cao, ; Zhan-You Wang,
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7
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Hino C, Xu Y, Xiao J, Baylink DJ, Reeves ME, Cao H. The potential role of the thymus in immunotherapies for acute myeloid leukemia. Front Immunol 2023; 14:1102517. [PMID: 36814919 PMCID: PMC9940763 DOI: 10.3389/fimmu.2023.1102517] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Accepted: 01/20/2023] [Indexed: 02/09/2023] Open
Abstract
Understanding the factors which shape T-lymphocyte immunity is critical for the development and application of future immunotherapeutic strategies in treating hematological malignancies. The thymus, a specialized central lymphoid organ, plays important roles in generating a diverse T lymphocyte repertoire during the infantile and juvenile stages of humans. However, age-associated thymic involution and diseases or treatment associated injury result in a decline in its continuous role in the maintenance of T cell-mediated anti-tumor/virus immunity. Acute myeloid leukemia (AML) is an aggressive hematologic malignancy that mainly affects older adults, and the disease's progression is known to consist of an impaired immune surveillance including a reduction in naïve T cell output, a restriction in T cell receptor repertoire, and an increase in frequencies of regulatory T cells. As one of the most successful immunotherapies thus far developed for malignancy, T-cell-based adoptive cell therapies could be essential for the development of a durable effective treatment to eliminate residue leukemic cells (blasts) and prevent AML relapse. Thus, a detailed cellular and molecular landscape of how the adult thymus functions within the context of the AML microenvironment will provide new insights into both the immune-related pathogenesis and the regeneration of a functional immune system against leukemia in AML patients. Herein, we review the available evidence supporting the potential correlation between thymic dysfunction and T-lymphocyte impairment with the ontogeny of AML (II-VI). We then discuss how the thymus could impact current and future therapeutic approaches in AML (VII). Finally, we review various strategies to rejuvenate thymic function to improve the precision and efficacy of cancer immunotherapy (VIII).
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Affiliation(s)
- Christopher Hino
- Department of Internal Medicine, Loma Linda University, Loma Linda, CA, United States
| | - Yi Xu
- Division of Hematology and Oncology, Department of Medicine, Loma Linda University, Loma Linda, CA, United States.,Division of Regenerative Medicine, Department of Medicine, Loma Linda University, Loma Linda, CA, United States.,Loma Linda University Cancer Center, Loma Linda, CA, United States
| | - Jeffrey Xiao
- Division of Regenerative Medicine, Department of Medicine, Loma Linda University, Loma Linda, CA, United States
| | - David J Baylink
- Division of Regenerative Medicine, Department of Medicine, Loma Linda University, Loma Linda, CA, United States
| | - Mark E Reeves
- Division of Hematology and Oncology, Department of Medicine, Loma Linda University, Loma Linda, CA, United States.,Loma Linda University Cancer Center, Loma Linda, CA, United States
| | - Huynh Cao
- Division of Hematology and Oncology, Department of Medicine, Loma Linda University, Loma Linda, CA, United States.,Loma Linda University Cancer Center, Loma Linda, CA, United States
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8
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Wang W, Thomas R, Su DM. Are aged pTreg cells "the more the better"? Aging (Albany NY) 2022; 14:9777-9778. [PMID: 36566022 PMCID: PMC9831728 DOI: 10.18632/aging.204454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 12/06/2022] [Indexed: 12/24/2022]
Affiliation(s)
- Weikan Wang
- Current affiliation: Department of Neurology, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, China
| | - Rachel Thomas
- Current affiliation: Alcon Research, LLC, Fort Worth, TX 76134, USA
| | - Dong-Ming Su
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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9
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Wang Y, Dong C, Han Y, Gu Z, Sun C. Immunosenescence, aging and successful aging. Front Immunol 2022; 13:942796. [PMID: 35983061 PMCID: PMC9379926 DOI: 10.3389/fimmu.2022.942796] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 07/08/2022] [Indexed: 12/24/2022] Open
Abstract
Aging induces a series of immune related changes, which is called immunosenescence, playing important roles in many age-related diseases, especially neurodegenerative diseases, tumors, cardiovascular diseases, autoimmune diseases and coronavirus disease 2019(COVID-19). However, the mechanism of immunosenescence, the association with aging and successful aging, and the effects on diseases are not revealed obviously. In order to provide theoretical basis for preventing or controlling diseases effectively and achieve successful aging, we conducted the review and found that changes of aging-related phenotypes, deterioration of immune organ function and alterations of immune cell subsets participated in the process of immunosenescence, which had great effects on the occurrence and development of age-related diseases.
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Affiliation(s)
- Yunan Wang
- Department of Rheumatology, Affiliated Hospital of Nantong University, Medical School of Nantong University, Nantong, China
| | - Chen Dong
- Department of Rheumatology, Affiliated Hospital of Nantong University, Nantong, China
| | - Yudian Han
- Information Center, The First People’s Hospital of Nantong City, Nantong, China
| | - Zhifeng Gu
- Department of Rheumatology, Affiliated Hospital of Nantong University, Nantong, China
- *Correspondence: Zhifeng Gu, ; Chi Sun,
| | - Chi Sun
- Department of Geriatrics, Affiliated Hospital of Nantong University, Nantong, China
- *Correspondence: Zhifeng Gu, ; Chi Sun,
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10
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Das S, Nasim F, Mishra R, Mishra R. Thymic and Peripheral T-cell Polarization in an Experimental Model of Russell's Viper Venom-induced Acute Kidney Injury. Immunol Invest 2022; 51:1452-1470. [PMID: 34380374 DOI: 10.1080/08820139.2021.1960369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Venom pathology is not restricted to the direct toxic effects of venom. Immunoinflammatory alteration as the etiology of snake venom-induced acute kidney injury (SAKI) is a less trodden path toward the development of alternative therapeutic approach. In the present study, we have associated the crest of renal damage stage to the immunological alteration, as reflected in thymic and peripheral T cell polarization in the murine model of SAKI. Renal injury in mice was confirmed from significant dysuresis and adversely altered biochemical renal markers. Histopathological alterations, as revealed by marked tubular and glomerular damage, reaffirmed kidney injury. SAKI is accompanied by significant inflammatory changes as indicated by neutrophilic leucocytosis, increased neutrophil to lymphocyte ratio and plasma CRP levels. Thymic immunophenotyping revealed significantly increased CD8+ cytotoxic T cell, and CD25+ both single positive population (p = .017-0.010) and CD44-CD25+ double negative population (DN3) (p = .002) accompanied by an insignificantly reduced CD4+ helper T cells (p = .451). Peripheral immunophenotyping revealed similar pattern as indicated by reduced helper T cells (p = .002) associated with significantly elevated cytotoxic T cells (p = .009) and CD25+ subset of both helper (p = .002) and cytotoxic (p = .024) T cells. The IL-10+ subset of both CD25+ and CD25- T cells were also found to be significantly elevated in the SAKI group (p ≤ 0.020) suggesting an immunosuppressive phenotype in SAKI. It can be concluded that T cells responds to venom-induced renal injury particularly through IL-10+ reparative phenotypes which are known for their immunosuppressive and anti-inflammatory activity.
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Affiliation(s)
- Sreyasi Das
- Department of Physiology, Ananda Mohan College, Kolkata, India
- Department of Physiology, University of Calcutta, Kolkata, India
| | - Farhat Nasim
- Department of Physiology, University of Calcutta, Kolkata, India
| | - Roshnara Mishra
- Department of Physiology, University of Calcutta, Kolkata, India
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11
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Lancaster JN, Keatinge‐Clay DE, Srinivasan J, Li Y, Selden HJ, Nam S, Richie ER, Ehrlich LIR. Central tolerance is impaired in the middle-aged thymic environment. Aging Cell 2022; 21:e13624. [PMID: 35561351 PMCID: PMC9197411 DOI: 10.1111/acel.13624] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 04/03/2022] [Accepted: 04/20/2022] [Indexed: 12/03/2022] Open
Abstract
One of the earliest hallmarks of immune aging is thymus involution, which not only reduces the number of newly generated and exported T cells, but also alters the composition and organization of the thymus microenvironment. Thymic T‐cell export continues into adulthood, yet the impact of thymus involution on the quality of newly generated T‐cell clones is not well established. Notably, the number and proportion of medullary thymic epithelial cells (mTECs) and expression of tissue‐restricted antigens (TRAs) decline with age, suggesting the involuting thymus may not promote efficient central tolerance. Here, we demonstrate that the middle‐aged thymic environment does not support rapid motility of medullary thymocytes, potentially diminishing their ability to scan antigen presenting cells (APCs) that display the diverse self‐antigens that induce central tolerance. Consistent with this possibility, thymic slice assays reveal that the middle‐aged thymic environment does not support efficient negative selection or regulatory T‐cell (Treg) induction of thymocytes responsive to either TRAs or ubiquitous self‐antigens. This decline in central tolerance is not universal, but instead impacts lower‐avidity self‐antigens that are either less abundant or bind to TCRs with moderate affinities. Additionally, the decline in thymic tolerance by middle age is accompanied by both a reduction in mTECs and hematopoietic APC subsets that cooperate to drive central tolerance. Thus, age‐associated changes in the thymic environment result in impaired central tolerance against moderate‐avidity self‐antigens, potentially resulting in export of increasingly autoreactive naive T cells, with a deficit of Treg counterparts by middle age.
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Affiliation(s)
- Jessica N. Lancaster
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | | | - Jayashree Srinivasan
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Yu Li
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Hilary J. Selden
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Seohee Nam
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
| | - Ellen R. Richie
- Department of Epigenetics and Molecular Carcinogenesis The University of Texas MD Anderson Cancer Center Houston Texas USA
| | - Lauren I. R. Ehrlich
- Department of Molecular Biosciences The University of Texas at Austin Austin Texas USA
- Department of Oncology Dell Medical School at The University of Texas at Austin Austin Texas USA
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12
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Wang W, Thomas R, Oh J, Su D. Accumulation of pTreg cells is detrimental in late-onset (aged) mouse model of multiple sclerosis. Aging Cell 2022; 21:e13630. [PMID: 35615905 PMCID: PMC9197401 DOI: 10.1111/acel.13630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 03/22/2022] [Accepted: 05/03/2022] [Indexed: 11/26/2022] Open
Abstract
Although typically associated with onset in young adults, multiple sclerosis (MS) also attacks the elderly, which is termed late-onset MS. The disease can be recapitulated and studied in a mouse model, experimental autoimmune encephalomyelitis (EAE). The onset of induced EAE is delayed in aged mice, but disease severity is increased relative to young EAE mice. Given that CD4+ FoxP3+ regulatory T (Treg) cells play an ameliorative role in MS/EAE severity, and the aged immune system accumulates peripheral Treg (pTreg) cells, failure of these cells to prevent or ameliorate EAE disease is enigmatic. When analyzing the distribution of Treg cells in EAE mice, the aged mice exhibited a higher proportion of polyclonal (pan-) pTreg cells and a lower proportion of antigen-specific pTreg cells in the periphery but lower proportions of both pan- and antigen-specific Treg cells in the central nervous system (CNS). Furthermore, in the aged inflamed CNS, CNS-Treg cells exhibited a higher plasticity, and T effector (CNS-Teff) cells exhibited greater clonal expansion, disrupting the Treg/Teff balance. Transiently inhibiting FoxP3 or depleting pTreg cells partially corrected Treg distribution and restored the Treg/Teff balance in the aged inflamed CNS, thereby ameliorating the disease in the aged EAE mice. These results provide evidence and mechanism that accumulated aged pTreg cells play a detrimental role in neuronal inflammation of aged MS.
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Affiliation(s)
- Weikan Wang
- Department of Microbiology, Immunology, and Genetics University of North Texas Health Science Center Fort Worth Texas USA
| | | | - Jiyoung Oh
- Department of Pediatrics University of Texas Southwestern Medical Center Dallas Texas 75390 USA
| | - Dong‐Ming Su
- Department of Microbiology, Immunology, and Genetics University of North Texas Health Science Center Fort Worth Texas USA
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13
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Gulla S, Reddy MC, Reddy VC, Chitta S, Bhanoori M, Lomada D. Role of thymus in health and disease. Int Rev Immunol 2022; 42:347-363. [PMID: 35593192 DOI: 10.1080/08830185.2022.2064461] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/26/2022] [Accepted: 04/04/2022] [Indexed: 01/04/2023]
Abstract
The thymus is a primary lymphoid organ, essential for the development of T-cells that will protect from invading pathogens, immune disorders, and cancer. The thymus decreases in size and cellularity with age referred to as thymus involution or atrophy. This involution causes decreased T-cell development and decreased naive T-cell emigration to the periphery, increased proportion of memory T cells, and a restricted, altered T-cell receptor (TCR) repertoire. The changes in composition and function of the circulating T cell pool as a result of thymic involution led to increased susceptibility to infectious diseases including the recent COVID and a higher risk for autoimmune disorders and cancers. Thymic involution consisting of both structural and functional loss of the thymus has a deleterious effect on T cell development, T cell selection, and tolerance. The mechanisms which act on the structural (cortex and medulla) matrix of the thymus, the gradual accumulation of genetic mutations, and altered gene expressions may lead to immunosenescence as a result of thymus involution. Understanding the molecular mechanisms behind thymic involution is critical for identifying diagnostic biomarkers and targets for treatment help to develop strategies to mitigate thymic involution-associated complications. This review is focused on the consequences of thymic involution in infections, immune disorders, and diseases, identifying potential checkpoints and potential approaches to sustain or restore the function of the thymus particularly in elderly and immune-compromised individuals.
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Affiliation(s)
- Surendra Gulla
- Department of Biotechnology and Bioinformatics, Yogi Vemana University, Kadapa, Andhra Pradesh, India
| | - Madhava C Reddy
- Department of Biotechnology and Bioinformatics, Yogi Vemana University, Kadapa, Andhra Pradesh, India
| | - Vajra C Reddy
- Katuri Medical College and Hospital, Chinnakondrupadu, Guntur, India
| | | | - Manjula Bhanoori
- Department of Biochemistry, Osmania University, Hyderabad, Telangana State, India
| | - Dakshayani Lomada
- Department of Genetics and Genomics, Yogi Vemana University, Kadapa, Andhra Pradesh, India
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14
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Role of T Regulatory Cells and Myeloid-Derived Suppressor Cells in COVID-19. J Immunol Res 2022; 2022:5545319. [PMID: 35497875 PMCID: PMC9042623 DOI: 10.1155/2022/5545319] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Revised: 03/13/2022] [Accepted: 03/28/2022] [Indexed: 01/08/2023] Open
Abstract
Coronavirus disease 2019 (COVID-19) has been raised as a pandemic disease since December 2019. Immunosuppressive cells including T regulatory cells (Tregs) and myeloid-derived suppressor cells (MDSCs) are key players in immunological tolerance and immunoregulation; however, they contribute to the pathogenesis of different diseases including infections. Tregs have been shown to impair the protective role of CD8+ T lymphocytes against viral infections. In COVID-19 patients, most studies reported reduction, while few other studies found elevation in Treg levels. Moreover, Tregs have a dual role, depending on the different stages of COVID-19 disease. At early stages of COVID-19, Tregs have a critical role in decreasing antiviral immune responses, and consequently reducing the viral clearance. On the other side, during late stages, Tregs reduce inflammation-induced organ damage. Therefore, inhibition of Tregs in early stages and their expansion in late stages have potentials to improve clinical outcomes. In viral infections, MDSC levels are highly increased, and they have the potential to suppress T cell proliferation and reduce viral clearance. Some subsets of MDSCs are expanded in the blood of COVID-19 patients; however, there is a controversy whether this expansion has pathogenic or protective effects in COVID-19 patients. In conclusion, further studies are required to investigate the role and function of immunosuppressive cells and their potentials as prognostic biomarkers and therapeutic targets in COVID-19 patients.
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15
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Interconnections between Inflammageing and Immunosenescence during Ageing. Cells 2022; 11:cells11030359. [PMID: 35159168 PMCID: PMC8834134 DOI: 10.3390/cells11030359] [Citation(s) in RCA: 71] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 01/13/2022] [Accepted: 01/15/2022] [Indexed: 02/04/2023] Open
Abstract
Acute inflammation is a physiological response to injury or infection, with a cascade of steps that ultimately lead to the recruitment of immune cells to clear invading pathogens and heal wounds. However, chronic inflammation arising from the continued presence of the initial trigger, or the dysfunction of signalling and/or effector pathways, is harmful to health. While successful ageing in older adults, including centenarians, is associated with low levels of inflammation, elevated inflammation increases the risk of poor health and death. Hence inflammation has been described as one of seven pillars of ageing. Age-associated sterile, chronic, and low-grade inflammation is commonly termed inflammageing-it is not simply a consequence of increasing chronological age, but is also a marker of biological ageing, multimorbidity, and mortality risk. While inflammageing was initially thought to be caused by "continuous antigenic load and stress", reports from the last two decades describe a much more complex phenomenon also involving cellular senescence and the ageing of the immune system. In this review, we explore some of the main sources and consequences of inflammageing in the context of immunosenescence and highlight potential interventions. In particular, we assess the contribution of cellular senescence to age-associated inflammation, identify patterns of pro- and anti-inflammatory markers characteristic of inflammageing, describe alterations in the ageing immune system that lead to elevated inflammation, and finally assess the ways that diet, exercise, and pharmacological interventions can reduce inflammageing and thus, improve later life health.
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16
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How Immunosenescence and Inflammaging May Contribute to Hyperinflammatory Syndrome in COVID-19. Int J Mol Sci 2021; 22:ijms222212539. [PMID: 34830421 PMCID: PMC8618618 DOI: 10.3390/ijms222212539] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/16/2022] Open
Abstract
Aging is characterized by the dynamic remodeling of the immune system designated “immunosenescence,” and is associated with altered hematopoiesis, thymic involution, and lifelong immune stimulation by multitudinous chronic stressors, including the cytomegalovirus (CMV). Such alterations may contribute to a lowered proportion of naïve T-cells and to reduced diversity of the T-cell repertoire. In the peripheral circulation, a shift occurs towards accumulations of T and B-cell populations with memory phenotypes, and to accumulation of putatively senescent and exhausted immune cells. The aging-related accumulations of functionally exhausted memory T lymphocytes, commonly secreting pro-inflammatory cytokines, together with mediators and factors of the innate immune system, are considered to contribute to the low-grade inflammation (inflammaging) often observed in elderly people. These senescent immune cells not only secrete inflammatory mediators, but are also able to negatively modulate their environments. In this review, we give a short summary of the ways that immunosenescence, inflammaging, and CMV infection may cause insufficient immune responses, contribute to the establishment of the hyperinflammatory syndrome and impact the severity of the coronavirus disease 2019 (COVID-19) in elderly people.
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17
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Stojić-Vukanić Z, Pilipović I, Arsenović-Ranin N, Dimitrijević M, Leposavić G. Sex-specific remodeling of T-cell compartment with aging: Implications for rat susceptibility to central nervous system autoimmune diseases. Immunol Lett 2021; 239:42-59. [PMID: 34418487 DOI: 10.1016/j.imlet.2021.08.003] [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: 02/08/2021] [Revised: 06/12/2021] [Accepted: 08/12/2021] [Indexed: 11/15/2022]
Abstract
The incidence of multiple sclerosis (MS) and susceptibility of animals to experimental autoimmune encephalomyelitis (EAE), the most commonly used experimental model of MS, decrease with aging. Generally, autoimmune diseases develop as the ultimate outcome of an imbalance between damaging immune responses against self and regulatory immune responses (keeping the former under control). Thus, in this review the age-related changes possibly underlying this balance were discussed. Specifically, considering the central role of T cells in MS/EAE, the impact of aging on overall functional capacity (reflecting both overall count and individual functional cell properties) of self-reactive conventional T cells (Tcons) and FoxP3+ regulatory T cells (Tregs), as the most potent immunoregulatory/suppressive cells, was analyzed, as well. The analysis encompasses three distinct compartments: thymus (the primary lymphoid organ responsible for the elimination of self-reactive T cells - negative selection and the generation of Tregs, compensating for imperfections of the negative selection), peripheral blood/lymphoid tissues ("afferent" compartment), and brain/spinal cord tissues ("target" compartment). Given that the incidence of MS and susceptibility of animals to EAE are greater in women/females than in age-matched men/males, sex as independent variable was also considered. In conclusion, with aging, sex-specific alterations in the balance of self-reactive Tcons/Tregs are likely to occur not only in the thymus/"afferent" compartment, but also in the "target" compartment, reflecting multifaceted changes in both T-cell types. Their in depth understanding is important not only for envisaging effects of aging, but also for designing interventions to slow-down aging without any adverse effect on incidence of autoimmune diseases.
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Affiliation(s)
- Zorica Stojić-Vukanić
- Department of Microbiology and Immunology, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia
| | - Ivan Pilipović
- Immunology Research Centre "Branislav Janković", Institute of Virology, Vaccines and Sera "Torlak", Belgrade, Serbia
| | - Nevena Arsenović-Ranin
- Department of Microbiology and Immunology, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia
| | - Mirjana Dimitrijević
- Department of Immunology, University of Belgrade - Institute for Biological Research "Siniša Stanković" - National Institute of Republic of Serbia, Belgrade, Serbia
| | - Gordana Leposavić
- Department of Pathobiology, University of Belgrade - Faculty of Pharmacy, Belgrade, Serbia.
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18
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Werlen G, Jain R, Jacinto E. MTOR Signaling and Metabolism in Early T Cell Development. Genes (Basel) 2021; 12:genes12050728. [PMID: 34068092 PMCID: PMC8152735 DOI: 10.3390/genes12050728] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 05/10/2021] [Accepted: 05/10/2021] [Indexed: 12/12/2022] Open
Abstract
The mechanistic target of rapamycin (mTOR) controls cell fate and responses via its functions in regulating metabolism. Its role in controlling immunity was unraveled by early studies on the immunosuppressive properties of rapamycin. Recent studies have provided insights on how metabolic reprogramming and mTOR signaling impact peripheral T cell activation and fate. The contribution of mTOR and metabolism during early T-cell development in the thymus is also emerging and is the subject of this review. Two major T lineages with distinct immune functions and peripheral homing organs diverge during early thymic development; the αβ- and γδ-T cells, which are defined by their respective TCR subunits. Thymic T-regulatory cells, which have immunosuppressive functions, also develop in the thymus from positively selected αβ-T cells. Here, we review recent findings on how the two mTOR protein complexes, mTORC1 and mTORC2, and the signaling molecules involved in the mTOR pathway are involved in thymocyte differentiation. We discuss emerging views on how metabolic remodeling impacts early T cell development and how this can be mediated via mTOR signaling.
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19
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Srinivasan J, Lancaster JN, Singarapu N, Hale LP, Ehrlich LIR, Richie ER. Age-Related Changes in Thymic Central Tolerance. Front Immunol 2021; 12:676236. [PMID: 33968086 PMCID: PMC8100025 DOI: 10.3389/fimmu.2021.676236] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 04/06/2021] [Indexed: 01/03/2023] Open
Abstract
Thymic epithelial cells (TECs) and hematopoietic antigen presenting cells (HAPCs) in the thymus microenvironment provide essential signals to self-reactive thymocytes that induce either negative selection or generation of regulatory T cells (Treg), both of which are required to establish and maintain central tolerance throughout life. HAPCs and TECs are comprised of multiple subsets that play distinct and overlapping roles in central tolerance. Changes that occur in the composition and function of TEC and HAPC subsets across the lifespan have potential consequences for central tolerance. In keeping with this possibility, there are age-associated changes in the cellular composition and function of T cells and Treg. This review summarizes changes in T cell and Treg function during the perinatal to adult transition and in the course of normal aging, and relates these changes to age-associated alterations in thymic HAPC and TEC subsets.
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Affiliation(s)
- Jayashree Srinivasan
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, United States
| | | | - Nandini Singarapu
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Smithville, TX, United States
| | - Laura P Hale
- Department of Pathology, Duke University School of Medicine, Durham, NC, United States
| | - Lauren I R Ehrlich
- Department of Molecular Biosciences, Institute of Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, United States.,Livestrong Cancer Institutes, Dell Medical School, The University of Texas at Austin, Austin, TX, United States
| | - Ellen R Richie
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas M.D. Anderson Cancer Center, Smithville, TX, United States
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20
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Thomas R, Oh J, Wang W, Su DM. Thymic atrophy creates holes in Treg-mediated immuno-regulation via impairment of an antigen-specific clone. Immunology 2021; 163:478-492. [PMID: 33786850 DOI: 10.1111/imm.13333] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/18/2021] [Accepted: 03/19/2021] [Indexed: 12/14/2022] Open
Abstract
Age-related thymic atrophy results in reduced output of naïve conventional T (Tcon) cells. However, its impact on regulatory T (Treg) cells is insufficiently understood. Given evidence that thymic Treg (tTreg) cell generation is enhanced in the aged, atrophy thymus and that the aged periphery accumulates peripheral Treg (pTreg) cells, we asked why these Treg cells are unable to effectively attenuate increased autoreactivity-induced chronic inflammation in the elderly. We designed a mock-self-antigen chimera mouse model, in which membrane-bound ovalbumin (mOVA) transgenic mice, bearing a FoxN1-floxed gene for induction of conditional thymic atrophy, received OVA-specific (OT-II) T-cell receptor (TCR) transgenic progenitor cells. The chimeric mice with thymic atrophy exhibited a significant decrease in OVA-specific tTreg and pTreg cells but not polyclonal (pan)-Treg cells. These OVA-specific pTreg cells were significantly less able to suppress OVA-specific stimulation-induced proliferation in vitro and exhibited lower FoxP3 expression. Additionally, we conducted preliminary TCR repertoire diversity sequencing for Treg cells among recent thymic emigrants (RTEs) from RagGFP -FoxP3RFP dual-reporter mice and observed a trend for decreased diversity in mice with thymic atrophy compared to littermates with normal thymus. These data indicate that although the effects of age-related thymic atrophy do not affect pan-Treg generation, certain tissue-specific Treg clones may experience abnormal agonist selection. This, combined with enhanced pan-pTreg cells, may greatly contribute to age-related chronic inflammation, even in the absence of acute autoimmune disease in the elderly.
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Affiliation(s)
- Rachel Thomas
- Graduate School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Jiyoung Oh
- Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Weikan Wang
- Graduate School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, USA
| | - Dong-Ming Su
- Department of Microbiology, Immunology and Genetics, University of North Texas Health Science Center, Fort Worth, TX, USA
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21
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Martinez F, Novarino J, Mejía JE, Fazilleau N, Aloulou M. Ageing of T-dependent B cell responses. Immunol Lett 2021; 233:97-103. [PMID: 33811941 DOI: 10.1016/j.imlet.2021.03.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 03/24/2021] [Accepted: 03/29/2021] [Indexed: 12/16/2022]
Abstract
The human immune system is in continuous interaction with environmental factors (pathogens, exercise, stress, pollutants, diet, vaccines, and therapeutics) that condition its efficiency by promoting or moderating multiple immune mechanisms. While the deleterious impact of external factors can be avoided or limited, the immune system itself grows weaker with age. Immune cells persist in the elderly, and the observed decline of cellular immunity is related to cellular senescence. Immunosenescence, which affects both T and B cells, erodes lymphocyte-dependent responses to vaccines and pathogens. Germinal centers (GCs), the organized lymphoid structures where B cells engage in affinity maturation, are regulated by follicular helper (Tfh) and follicular regulatory (Tfr) T cells, the major T cell components of GCs. This review discusses how age-related changes affect Tfh and Tfr cells as key components of B cell immunity, and how they ultimately shape the response of the ageing immune system to vaccines and infectious challenges.
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Affiliation(s)
- Fanny Martinez
- Infinity, Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, Inserm U1291, CNRS U5051, Toulouse, France
| | - Julien Novarino
- Infinity, Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, Inserm U1291, CNRS U5051, Toulouse, France
| | - José Enrique Mejía
- Infinity, Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, Inserm U1291, CNRS U5051, Toulouse, France
| | - Nicolas Fazilleau
- Infinity, Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, Inserm U1291, CNRS U5051, Toulouse, France.
| | - Meryem Aloulou
- Infinity, Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, Inserm U1291, CNRS U5051, Toulouse, France.
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22
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Elfaki Y, Robert PA, Binz C, Falk CS, Bruder D, Prinz I, Floess S, Meyer-Hermann M, Huehn J. Influenza A virus-induced thymus atrophy differentially affects dynamics of conventional and regulatory T-cell development in mice. Eur J Immunol 2021; 51:1166-1181. [PMID: 33638148 DOI: 10.1002/eji.202048981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 12/23/2020] [Accepted: 02/18/2021] [Indexed: 01/26/2023]
Abstract
Foxp3+ Treg cells, which are crucial for maintenance of self-tolerance, mainly develop within the thymus, where they arise from CD25+ Foxp3- or CD25- Foxp3+ Treg cell precursors. Although it is known that infections can cause transient thymic involution, the impact of infection-induced thymus atrophy on thymic Treg (tTreg) cell development is unknown. Here, we infected mice with influenza A virus (IAV) and studied thymocyte population dynamics post infection. IAV infection caused a massive, but transient thymic involution, dominated by a loss of CD4+ CD8+ double-positive (DP) thymocytes, which was accompanied by a significant increase in the frequency of CD25+ Foxp3+ tTreg cells. Differential apoptosis susceptibility could be experimentally excluded as a reason for the relative tTreg cell increase, and mathematical modeling suggested that enhanced tTreg cell generation cannot explain the increased frequency of tTreg cells. Yet, an increased death of DP thymocytes and augmented exit of single-positive (SP) thymocytes was suggested to be causative. Interestingly, IAV-induced thymus atrophy resulted in a significantly reduced T-cell receptor (TCR) repertoire diversity of newly produced tTreg cells. Taken together, IAV-induced thymus atrophy is substantially altering the dynamics of major thymocyte populations, finally resulting in a relative increase of tTreg cells with an altered TCR repertoire.
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Affiliation(s)
- Yassin Elfaki
- Department of Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Philippe A Robert
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Christoph Binz
- Institute of Immunology, Hannover Medical School, Hannover, Germany
| | - Christine S Falk
- Institute of Transplant Immunology, Hannover Medical School, Hannover, Germany
| | - Dunja Bruder
- Infection Immunology Group, Institute of Medical Microbiology, Infection Control and Prevention, Health Campus Immunology, Infectiology and Inflammation, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.,Immune Regulation Group, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Immo Prinz
- Institute of Immunology, Hannover Medical School, Hannover, Germany.,Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
| | - Stefan Floess
- Department of Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Michael Meyer-Hermann
- Department of Systems Immunology and Braunschweig Integrated Centre of Systems Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany.,Institute for Biochemistry, Biotechnology and Bioinformatics, Technical University Braunschweig, Braunschweig, Germany
| | - Jochen Huehn
- Department of Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Cluster of Excellence RESIST (EXC 2155), Hannover Medical School, Hannover, Germany
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23
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Thymic Aging May Be Associated with COVID-19 Pathophysiology in the Elderly. Cells 2021; 10:cells10030628. [PMID: 33808998 PMCID: PMC8001029 DOI: 10.3390/cells10030628] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/01/2021] [Accepted: 03/10/2021] [Indexed: 02/06/2023] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused the global pandemic of coronavirus disease 2019 (COVID-19) and particularly exhibits severe symptoms and mortality in elderly individuals. Mounting evidence shows that the characteristics of the age-related clinical severity of COVID-19 are attributed to insufficient antiviral immune function and excessive self-damaging immune reaction, involving T cell immunity and associated with pre-existing basal inflammation in the elderly. Age-related changes to T cell immunosenescence is characterized by not only restricted T cell receptor (TCR) repertoire diversity, accumulation of exhausted and/or senescent memory T cells, but also by increased self-reactive T cell- and innate immune cell-induced chronic inflammation, and accumulated and functionally enhanced polyclonal regulatory T (Treg) cells. Many of these changes can be traced back to age-related thymic involution/degeneration. How these changes contribute to differences in COVID-19 disease severity between young and aged patients is an urgent area of investigation. Therefore, we attempt to connect various clues in this field by reviewing and discussing recent research on the role of the thymus and T cells in COVID-19 immunity during aging (a synergistic effect of diminished responses to pathogens and enhanced responses to self) impacting age-related clinical severity of COVID-19. We also address potential combinational strategies to rejuvenate multiple aging-impacted immune system checkpoints by revival of aged thymic function, boosting peripheral T cell responses, and alleviating chronic, basal inflammation to improve the efficiency of anti-SARS-CoV-2 immunity and vaccination in the elderly.
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24
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Oh J, Wang W, Thomas R, Su DM. Thymic rejuvenation via FOXN1-reprogrammed embryonic fibroblasts (FREFs) to counteract age-related inflammation. JCI Insight 2020; 5:140313. [PMID: 32790650 PMCID: PMC7526556 DOI: 10.1172/jci.insight.140313] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 07/31/2020] [Indexed: 12/13/2022] Open
Abstract
Age-associated systemic, chronic inflammation is partially attributed to increased self-autoreactivity, resulting from disruption of central tolerance in the aged, involuted thymus. This involution causally results from gradually decreased expression of the transcription factor FOXN1 in thymic epithelial cells (TECs), whereas exogenous FOXN1 in TECs can partially rescue age-related thymic involution. TECs induced from FOXN1-overexpressing embryonic fibroblasts can generate an ectopic de novo thymus under the kidney capsule, and intrathymic injection of naturally young TECs can lead to middle-aged thymus regrowth. Therefore, as a thymic rejuvenation strategy, we extended these 2 findings by combining them with 2 types of promoter-driven (Rosa26CreERT and FoxN1Cre) Cre-mediated FOXN1-reprogrammed embryonic fibroblasts (FREFs). We engrafted these FREFs directly into the aged murine thymus. We found substantial regrowth of the native aged thymus with rejuvenated architecture and function in both males and females, exhibiting increased thymopoiesis and reinforced thymocyte negative selection, along with reduced senescent T cells and autoreactive T cell–mediated inflammation in old mice. Therefore, this approach has preclinical significance and presents a strategy to potentially rescue decreased thymopoiesis and perturbed negative selection to substantially, albeit partially, restore defective central tolerance and reduce subclinical autoimmune symptoms in elderly people. Engrafting FOXN1-reprogrammed embryonic fibroblast directly into the aged murine thymus promoted regrowth of the native thymus with rejuvenated architecture and function.
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25
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Hager S, Fittler FJ, Wagner E, Bros M. Nucleic Acid-Based Approaches for Tumor Therapy. Cells 2020; 9:E2061. [PMID: 32917034 PMCID: PMC7564019 DOI: 10.3390/cells9092061] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/06/2020] [Accepted: 09/07/2020] [Indexed: 12/24/2022] Open
Abstract
Within the last decade, the introduction of checkpoint inhibitors proposed to boost the patients' anti-tumor immune response has proven the efficacy of immunotherapeutic approaches for tumor therapy. Furthermore, especially in the context of the development of biocompatible, cell type targeting nano-carriers, nucleic acid-based drugs aimed to initiate and to enhance anti-tumor responses have come of age. This review intends to provide a comprehensive overview of the current state of the therapeutic use of nucleic acids for cancer treatment on various levels, comprising (i) mRNA and DNA-based vaccines to be expressed by antigen presenting cells evoking sustained anti-tumor T cell responses, (ii) molecular adjuvants, (iii) strategies to inhibit/reprogram tumor-induced regulatory immune cells e.g., by RNA interference (RNAi), (iv) genetically tailored T cells and natural killer cells to directly recognize tumor antigens, and (v) killing of tumor cells, and reprograming of constituents of the tumor microenvironment by gene transfer and RNAi. Aside from further improvements of individual nucleic acid-based drugs, the major perspective for successful cancer therapy will be combination treatments employing conventional regimens as well as immunotherapeutics like checkpoint inhibitors and nucleic acid-based drugs, each acting on several levels to adequately counter-act tumor immune evasion.
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Affiliation(s)
- Simone Hager
- Department of Chemistry and Pharmacy, Ludwig-Maximilians-University (LMU), 81377 Munich, Germany;
| | | | - Ernst Wagner
- Department of Chemistry and Pharmacy, Ludwig-Maximilians-University (LMU), 81377 Munich, Germany;
| | - Matthias Bros
- Department of Dermatology, University Medical Center, 55131 Mainz, Germany;
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26
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Wei W, Wang Q, Pang S, Tan S, Sun J, Li M, Wang S, Sun D. Excessive fluoride exposure induces thymocyte apoptosis and impairs cell division: Roles of the PERK and IRE1 pathways. Toxicol Lett 2020; 328:35-44. [PMID: 32335163 DOI: 10.1016/j.toxlet.2020.04.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 04/16/2020] [Accepted: 04/19/2020] [Indexed: 01/21/2023]
Affiliation(s)
- Wei Wei
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Key Lab of Etiology and Epidemiology, Education Bureau of Heilongjiang Province & Ministry of Health (23618504), Harbin, Heilongjiang, 150081, China; Institution of Environmentally Related Diseases, Harbin Medical University, Harbin, Heilongjiang, 150081, China.
| | - Qian Wang
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Shujuan Pang
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China; Qingdao Hospital of Traditional Chinese Medicine (Qingdao Hiser hospital), Qingdao, Shandong Province, 266033, China
| | - Shiwen Tan
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Jing Sun
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Mengdi Li
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Shize Wang
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China
| | - Dianjun Sun
- Center for Endemic Disease Control, Chinese Center for Disease Control and Prevention, Harbin Medical University, Harbin, Heilongjiang, 150081, China
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27
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Churov AV, Mamashov KY, Novitskaia AV. Homeostasis and the functional roles of CD4 + Treg cells in aging. Immunol Lett 2020; 226:83-89. [PMID: 32717201 DOI: 10.1016/j.imlet.2020.07.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 07/08/2020] [Accepted: 07/15/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVE An upward trend in life expectancy has been observed in a majority of developed countries and leading to increasing in aging-related diseases. Aging is a risk factor for the development of widespread clinical conditions such as cardiovascular and autoimmune diseases, cancer, infections. Although studies have been very active, the problem of aging still remains one of the most obscure aspects of human biology. Regulatory T (Treg) cells with immunosuppressive properties have a pivotal role in the maintenance of immune homeostasis. Alterations in Treg cell functionality appear to be of great importance in the development of immune senescence and contribute to increased susceptibility to immune-mediated diseases with age. DESIGN This review highlights recent findings regarding the age-related changes in the numbers and functional activity of human Tregs. Some of the mechanisms that maintain the balance of Tregs during human aging are discussed. The possible roles of Tregs in the pathogenesis of diseases associated with advanced age are also considered. RESULTS Age-related systemic changes, such as thymic involution, hormonal status, and epigenetic modifications, may affect the state of the Treg population and trigger various diseases. These changes involve decline or amplification in the functional activity of Tregs, an increase in the memory Treg subset and shifting of a Th17/Treg balance. CONCLUSION Taken together, the reviewed data suggest equal or even increased Treg functionality with age. Thus, age-mediated Treg expansion and higher Treg activity may contribute to elevated immune suppression and increased risk of infections and cancer.
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Affiliation(s)
- Alexey V Churov
- Institute of Biology, Karelian Research Centre, Russian Academy of Sciences, Petrozavodsk, Russia.
| | | | - Anastasiia V Novitskaia
- Institute of Biology, Karelian Research Centre, Russian Academy of Sciences, Petrozavodsk, Russia
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Wang W, Thomas R, Sizova O, Su DM. Thymic Function Associated With Cancer Development, Relapse, and Antitumor Immunity - A Mini-Review. Front Immunol 2020; 11:773. [PMID: 32425946 PMCID: PMC7203483 DOI: 10.3389/fimmu.2020.00773] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 04/06/2020] [Indexed: 12/14/2022] Open
Abstract
The thymus is the central lymphoid organ for T cell development, a cradle of T cells, and for central tolerance establishment, an educator of T cells, maintaining homeostatic cellular immunity. T cell immunity is critical to control cancer occurrence, relapse, and antitumor immunity. Evidence on how aberrant thymic function influences cancer remains largely insufficient, however, there has been recent progress. For example, the involuted thymus results in reduced output of naïve T cells and a restricted T cell receptor (TCR) repertoire, inducing immunosenescence and potentially dampening immune surveillance of neoplasia. In addition, the involuted thymus relatively enhances regulatory T (Treg) cell generation. This coupled with age-related accumulation of Treg cells in the periphery, potentially provides a supportive microenvironment for tumors to escape T cell-mediated antitumor responses. Furthermore, acute thymic involution from chemotherapy can create a tumor reservoir, resulting from an inflammatory microenvironment in the thymus, which is suitable for disseminated tumor cells to hide, survive chemotherapy, and become dormant. This may eventually result in cancer metastatic relapse. On the other hand, if thymic involution is wisely taken advantage of, it may be potentially beneficial to antitumor immunity, since the involuted thymus increases output of self-reactive T cells, which may recognize certain tumor-associated self-antigens and enhance antitumor immunity, as demonstrated through depletion of autoimmune regulator (AIRE) gene in the thymus. Herein, we briefly review recent research progression regarding how altered thymic function modifies T cell immunity against tumors.
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Affiliation(s)
- Weikan Wang
- Cell Biology, Immunology, and Microbiology Graduate Program, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Rachel Thomas
- Cell Biology, Immunology, and Microbiology Graduate Program, Graduate School of Biomedical Sciences, University of North Texas Health Science Center, Fort Worth, TX, United States
| | - Olga Sizova
- Department of Hematopoietic Biology and Malignancy, The University of Texas MD Anderson Cancer Center, Houston, TX, United States
| | - Dong-Ming Su
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, TX, United States
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Deya-Martinez A, Flinn AM, Gennery AR. Neonatal thymectomy in children-accelerating the immunologic clock? J Allergy Clin Immunol 2020; 146:236-243. [PMID: 32169378 DOI: 10.1016/j.jaci.2020.02.028] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2019] [Revised: 01/25/2020] [Accepted: 02/26/2020] [Indexed: 12/29/2022]
Abstract
The thymus is critical for central tolerance and diverse T-lymphocyte repertoire development, to provide lifelong defense against pathogens while maintaining self-tolerance. Peak thymic output occurs in utero, during infancy, and in early childhood, diminishing throughout life. Infants with congenital heart disease requiring sternotomy often undergo thymectomy to clear the surgical field. The long-term effects of early thymectomy are just being appreciated. Many patients remain asymptomatic despite immunologic findings mirroring those of immunosenescence. Few develop increased infection or lymphoreticular malignancy risk. When considering the effects of infant thymectomy, patients with partial DiGeorge syndrome or hypomorphic recombination-activating gene (RAG) mutations may be instructive. These patients are lymphocytopenic, with increased early-onset infection and autoimmunity risk that is not seen in most patients who underwent thymectomy during infancy. The thymic structure of patients with partial DiGeorge syndrome or hypomorphic RAG is abnormal, with disrupted architecture inclining to perturbation of central tolerance. Similar findings may be seen in patients with myasthenia gravis, although disrupted peripheral tolerance may play a greater role in autoimmunity development. In conclusion, thymectomy during infancy may increase future risk of infection or autoimmunity, with premature immunosenescence mediated through disruption of central and peripheral tolerance mechanisms initiated by early cessation or diminution of thymic output. Ideally, some thymic tissue should be preserved at the time of surgery.
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Affiliation(s)
- Angela Deya-Martinez
- Functional Unit of Clinical Immunology and Primary Immunodeficiencies, Allergy and Clinical Immunology Department, Hospital Sant Joan de Déu, University of Barcelona, Pediatric Research Institute Sant Joan de Déu, Barcelona, Spain
| | - Aisling M Flinn
- Paediatric Immunology and Haematopoietic Stem Cell Transplantation, Great North Childrens' Hospital, Newcastle upon Tyne, United Kingdom
| | - Andrew R Gennery
- Paediatric Immunology and Haematopoietic Stem Cell Transplantation, Great North Childrens' Hospital, Newcastle upon Tyne, United Kingdom; Primary Immunodeficiency Group, Translational and Clinical Research Institute, Newcastle University, Newcastle upon Tyne, United Kingdom.
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Thomas R, Wang W, Su DM. Contributions of Age-Related Thymic Involution to Immunosenescence and Inflammaging. IMMUNITY & AGEING 2020; 17:2. [PMID: 31988649 PMCID: PMC6971920 DOI: 10.1186/s12979-020-0173-8] [Citation(s) in RCA: 199] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 01/02/2020] [Indexed: 01/10/2023]
Abstract
Immune system aging is characterized by the paradox of immunosenescence (insufficiency) and inflammaging (over-reaction), which incorporate two sides of the same coin, resulting in immune disorder. Immunosenescence refers to disruption in the structural architecture of immune organs and dysfunction in immune responses, resulting from both aged innate and adaptive immunity. Inflammaging, described as a chronic, sterile, systemic inflammatory condition associated with advanced age, is mainly attributed to somatic cellular senescence-associated secretory phenotype (SASP) and age-related autoimmune predisposition. However, the inability to reduce senescent somatic cells (SSCs), because of immunosenescence, exacerbates inflammaging. Age-related adaptive immune system deviations, particularly altered T cell function, are derived from age-related thymic atrophy or involution, a hallmark of thymic aging. Recently, there have been major developments in understanding how age-related thymic involution contributes to inflammaging and immunosenescence at the cellular and molecular levels, including genetic and epigenetic regulation, as well as developments of many potential rejuvenation strategies. Herein, we discuss the research progress uncovering how age-related thymic involution contributes to immunosenescence and inflammaging, as well as their intersection. We also describe how T cell adaptive immunity mediates inflammaging and plays a crucial role in the progression of age-related neurological and cardiovascular diseases, as well as cancer. We then briefly outline the underlying cellular and molecular mechanisms of age-related thymic involution, and finally summarize potential rejuvenation strategies to restore aged thymic function.
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Affiliation(s)
- Rachel Thomas
- Cell Biology, Immunology, and Microbiology Graduate Program, Graduate School of Biomedical Sciences, Fort Worth, Texas 76107 USA
| | - Weikan Wang
- Cell Biology, Immunology, and Microbiology Graduate Program, Graduate School of Biomedical Sciences, Fort Worth, Texas 76107 USA
| | - Dong-Ming Su
- 2Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas 76107 USA
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Du HM, Wang YJ, Liu X, Wang SL, Wu SM, Yuan Z, Zhu XK. Defective Central Immune Tolerance Induced by High-Dose D-Galactose Resembles Aging. BIOCHEMISTRY (MOSCOW) 2019; 84:617-626. [DOI: 10.1134/s000629791906004x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Fulop T, Witkowski JM, Olivieri F, Larbi A. The integration of inflammaging in age-related diseases. Semin Immunol 2018; 40:17-35. [DOI: 10.1016/j.smim.2018.09.003] [Citation(s) in RCA: 177] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Revised: 09/20/2018] [Accepted: 09/24/2018] [Indexed: 02/07/2023]
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Sizova O, Kuriatnikov D, Liu Y, Su DM. Atrophied Thymus, a Tumor Reservoir for Harboring Melanoma Cells. Mol Cancer Res 2018; 16:1652-1664. [DOI: 10.1158/1541-7786.mcr-18-0308] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/01/2018] [Accepted: 06/22/2018] [Indexed: 11/16/2022]
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Wang W, Wang L, Ruan L, Oh J, Dong X, Zhuge Q, Su DM. Extracellular vesicles extracted from young donor serum attenuate inflammaging via partially rejuvenating aged T-cell immunotolerance. FASEB J 2018; 32:fj201800059R. [PMID: 29782203 PMCID: PMC6181631 DOI: 10.1096/fj.201800059r] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 04/30/2018] [Indexed: 12/27/2022]
Abstract
Biologic aging results in a chronic inflammatory condition, termed inflammaging, which establishes a risk for such age-related diseases as neurocardiovascular diseases; therefore, it is of great importance to develop rejuvenation strategies that are able to attenuate inflammaging as a means of intervention for age-related diseases. A promising rejuvenation factor that is present in young blood has been found that can make aged neurons younger; however, the component in the young blood and its mechanism of action are poorly elucidated. We assessed rejuvenation in naturally aged mice with extracellular vesicles (EVs) or exosomes extracted from young murine serum on the basis of different spectrums of microRNAs in these vesicles from young and old sera. We found that EVs extracted from young donor mouse serum, rather than EVs extracted from old donor mouse serum or non-EV supernatant extracted from young donor mouse serum, were able to attenuate inflammaging in old mice. Inflammaging is attributed to multiple factors, one of which is thymic aging-released self-reactive T cell-induced pathology. We found that the attenuation of inflammaging after treatment with EVs from young serum partially contributed to the rejuvenation of thymic aging, which is characterized by partially reversed thymic involution, enhancement of negative selection signals, and reduced autoreactions in the periphery. Our results provide evidence for understanding of the potential rejuvenation factor in the young donor serum, which holds great promise for the development of novel therapeutics to reduce morbidity and mortality caused by age-related inflammatory diseases.-Wang, W., Wang, L., Ruan, L., Oh, J., Dong, X., Zhuge, Q., Su, D.-M. Extracellular vesicles extracted from young donor serum attenuate inflammaging via partially rejuvenating aged T-cell immunotolerance.
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Affiliation(s)
- Weikan Wang
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas, USA
- Zhejiang Provincial Key Laboratory of Aging and Neurological Disorder Research, First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Liefeng Wang
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas, USA
- Department of Biotechnology, Gannan Medical University, Ganzhou, China
| | - Linhui Ruan
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas, USA
- Zhejiang Provincial Key Laboratory of Aging and Neurological Disorder Research, First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Jiyoung Oh
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Xiaowei Dong
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Qichuan Zhuge
- Zhejiang Provincial Key Laboratory of Aging and Neurological Disorder Research, First Affiliated Hospital, Wenzhou Medical University, Wenzhou, China
| | - Dong-Ming Su
- Department of Microbiology, Immunology, and Genetics, University of North Texas Health Science Center, Fort Worth, Texas, USA
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Pan Y, Xiong M, Chen R, Ma Y, Corman C, Maricos M, Kindler U, Semtner M, Chen YH, Dahiya S, Gutmann DH. Athymic mice reveal a requirement for T-cell-microglia interactions in establishing a microenvironment supportive of Nf1 low-grade glioma growth. Genes Dev 2018; 32:491-496. [PMID: 29632086 PMCID: PMC5959233 DOI: 10.1101/gad.310797.117] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 03/13/2018] [Indexed: 12/21/2022]
Abstract
Murine Neurofibromatosis-1 (Nf1) optic low-grade glioma (LGG) stem cells (o-GSCs) form glioma-like lesions in wild-type, but not athymic, mice following transplantation. Here, Pan et al. show that the inability of athymic mice to support o-GSC engraftment results from impaired brain microglia/macrophage function, including reduced expression of Ccr2 and Ccl5, both of which are required for o-GSC engraftment and Nf1 optic glioma growth. Pediatric low-grade gliomas (LGGs) frequently do not engraft in immunocompromised mice, limiting their use as an experimental platform. In contrast, murine Neurofibromatosis-1 (Nf1) optic LGG stem cells (o-GSCs) form glioma-like lesions in wild-type, but not athymic, mice following transplantation. Here, we show that the inability of athymic mice to support o-GSC engraftment results from impaired microglia/macrophage function, including reduced expression of Ccr2 and Ccl5, both of which are required for o-GSC engraftment and Nf1 optic glioma growth. Impaired Ccr2 and Ccl5 expression in athymic microglia/macrophages was restored by T-cell exposure, establishing T-cell–microglia/macrophage interactions as critical stromal determinants that support NF1 LGG growth.
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Affiliation(s)
- Yuan Pan
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Min Xiong
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.,Reproductive Medicine Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Ran Chen
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Yu Ma
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Courtney Corman
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Meron Maricos
- Cellular Neuroscience, Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin 13125, Germany
| | - Urs Kindler
- Cellular Neuroscience, Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin 13125, Germany
| | - Marcus Semtner
- Cellular Neuroscience, Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association (MDC), Berlin 13125, Germany
| | - Yi-Hsien Chen
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.,Genome Engineering and iPSC Center (GEIC), Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Sonika Dahiya
- Division of Neuropathology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - David H Gutmann
- Department of Neurology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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