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Xu LL, Chen X, Cheng JP. The effect of T cell aging on the change of human tissue structure. Immun Ageing 2024; 21:26. [PMID: 38689298 PMCID: PMC11059612 DOI: 10.1186/s12979-024-00433-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Accepted: 04/23/2024] [Indexed: 05/02/2024]
Abstract
The trend of aging of the global population is becoming more and more significant, and the incidence of age-related diseases continues to rise.This phenomenon makes the problem of aging gradually attracted wide attention of the society, and gradually developed into an independent research field.As a vital defense mechanism of the human body, the immune system changes significantly during the aging process.Age-induced changes in the body's immune system are considered harmful and are commonly referred to as immune aging, which may represent the beginning of systemic aging.Immune cells, especially T cells, are the biggest influencers and participants in age-related deterioration of immune function, making older people more susceptible to different age-related diseases.More and more evidence shows that T cells play an important role in the change of human tissue structure after aging, which fundamentally affects the health and survival of the elderly.In this review, we discuss the general characteristics of age-related T cell immune alterations and the possible effects of aging T cells in various tissue structures in the human body.
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Affiliation(s)
- Ling-Ling Xu
- Medical College, School of Medicine, Wuhan University of Science and Technology, Wuhan, 430065, Hubei, China
| | - Xiang Chen
- Medical College, School of Medicine, Wuhan University of Science and Technology, Wuhan, 430065, Hubei, China
| | - Jing-Ping Cheng
- Department of Gerontology, CR & WISCO General Hospital, Wuhan University of Science and Technology, Wuhan, Hubei, 430080, China.
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2
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Giuliani A, Giudetti AM, Vergara D, Del Coco L, Ramini D, Caccese S, Sbriscia M, Graciotti L, Fulgenzi G, Tiano L, Fanizzi FP, Olivieri F, Rippo MR, Sabbatinelli J. Senescent Endothelial Cells Sustain Their Senescence-Associated Secretory Phenotype (SASP) through Enhanced Fatty Acid Oxidation. Antioxidants (Basel) 2023; 12:1956. [PMID: 38001810 PMCID: PMC10668971 DOI: 10.3390/antiox12111956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 10/25/2023] [Accepted: 10/30/2023] [Indexed: 11/26/2023] Open
Abstract
Cellular senescence is closely linked to endothelial dysfunction, a key factor in age-related vascular diseases. Senescent endothelial cells exhibit a proinflammatory phenotype known as SASP, leading to chronic inflammation (inflammaging) and vascular impairments. Albeit in a state of permanent growth arrest, senescent cells paradoxically display a high metabolic activity. The relationship between metabolism and inflammation is complex and varies across cell types and senescence inductions. While some cell types shift towards glycolysis during senescence, others favor oxidative phosphorylation (OXPHOS). Despite the high availability of oxygen, quiescent endothelial cells (ECs) tend to rely on glycolysis for their bioenergetic needs. However, there are limited data on the metabolic behavior of senescent ECs. Here, we characterized the metabolic profiles of young and senescent human umbilical vein endothelial cells (HUVECs) to establish a possible link between the metabolic status and the proinflammatory phenotype of senescent ECs. Senescent ECs internalize a smaller amount of glucose, have a lower glycolytic rate, and produce/release less lactate than younger cells. On the other hand, an increased fatty acid oxidation activity was observed in senescent HUVECs, together with a greater intracellular content of ATP. Interestingly, blockade of glycolysis with 2-deoxy-D-glucose in young cells resulted in enhanced production of proinflammatory cytokines, while the inhibition of carnitine palmitoyltransferase 1 (CPT1), a key rate-limiting enzyme of fatty acid oxidation, ameliorated the SASP in senescent ECs. In summary, metabolic changes in senescent ECs are complex, and this research seeks to uncover potential strategies for modulating these metabolic pathways to influence the SASP.
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Affiliation(s)
- Angelica Giuliani
- Cardiac Rehabilitation Unit of Bari Institute, Istituti Clinici Scientifici Maugeri IRCCS, 70124 Bari, Italy
| | - Anna Maria Giudetti
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (A.M.G.); (D.V.); (L.D.C.); (F.P.F.)
| | - Daniele Vergara
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (A.M.G.); (D.V.); (L.D.C.); (F.P.F.)
| | - Laura Del Coco
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (A.M.G.); (D.V.); (L.D.C.); (F.P.F.)
| | - Deborah Ramini
- Clinic of Laboratory and Precision Medicine, IRCCS INRCA, 60121 Ancona, Italy; (D.R.); (M.S.); (F.O.)
| | - Sara Caccese
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, 60126 Ancona, Italy; (S.C.); (G.F.); (M.R.R.); (J.S.)
| | - Matilde Sbriscia
- Clinic of Laboratory and Precision Medicine, IRCCS INRCA, 60121 Ancona, Italy; (D.R.); (M.S.); (F.O.)
| | - Laura Graciotti
- Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, 60126 Ancona, Italy;
| | - Gianluca Fulgenzi
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, 60126 Ancona, Italy; (S.C.); (G.F.); (M.R.R.); (J.S.)
| | - Luca Tiano
- Department of Life and Environmental Sciences, Università Politecnica delle Marche, 60131 Ancona, Italy;
| | - Francesco Paolo Fanizzi
- Department of Biological and Environmental Sciences and Technologies, University of Salento, 73100 Lecce, Italy; (A.M.G.); (D.V.); (L.D.C.); (F.P.F.)
| | - Fabiola Olivieri
- Clinic of Laboratory and Precision Medicine, IRCCS INRCA, 60121 Ancona, Italy; (D.R.); (M.S.); (F.O.)
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, 60126 Ancona, Italy; (S.C.); (G.F.); (M.R.R.); (J.S.)
| | - Maria Rita Rippo
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, 60126 Ancona, Italy; (S.C.); (G.F.); (M.R.R.); (J.S.)
| | - Jacopo Sabbatinelli
- Department of Clinical and Molecular Sciences, Università Politecnica delle Marche, 60126 Ancona, Italy; (S.C.); (G.F.); (M.R.R.); (J.S.)
- Laboratory Medicine Unit, Azienda Ospedaliero Universitaria delle Marche, 60126 Ancona, Italy
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3
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PTB Regulates the Metabolic Pathways and Cell Function of Keloid Fibroblasts through Alternative Splicing of PKM. Int J Mol Sci 2023; 24:ijms24065162. [PMID: 36982238 PMCID: PMC10049504 DOI: 10.3390/ijms24065162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/27/2023] [Accepted: 02/27/2023] [Indexed: 03/11/2023] Open
Abstract
Keloids, benign fibroproliferative cutaneous lesions, are characterized by abnormal growth and reprogramming of the metabolism of keloid fibroblasts (KFb). However, the underlying mechanisms of this kind of metabolic abnormality have not been identified. Our study aimed to investigate the molecules involved in aerobic glycolysis and its exact regulatory mechanisms in KFb. We discovered that polypyrimidine tract binding (PTB) was significantly upregulated in keloid tissues. siRNA silencing of PTB decreased the mRNA levels and protein expression levels of key glycolytic enzymes and corrected the dysregulation of glucose uptake and lactate production. In addition, mechanistic studies demonstrated that PTB promoted a change from pyruvate kinase muscle 1 (PKM1) to PKM2, and silencing PKM2 substantially reduced the PTB-induced increase in the flow of glycolysis. Moreover, PTB and PKM2 could also regulate the key enzymes in the tricarboxylic acid (TCA) cycle. Assays of cell function demonstrated that PTB promoted the proliferation and migration of KFb in vitro, and this phenomenon could be interrupted by PKM2 silencing. In conclusion, our findings indicate that PTB regulates aerobic glycolysis and the cell functions of KFb via alternative splicing of PKM.
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4
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Lu Y, Ruan Y, Hong P, Rui K, Liu Q, Wang S, Cui D. T-cell senescence: A crucial player in autoimmune diseases. Clin Immunol 2023; 248:109202. [PMID: 36470338 DOI: 10.1016/j.clim.2022.109202] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 10/24/2022] [Accepted: 11/23/2022] [Indexed: 12/12/2022]
Abstract
Senescent T cells are proliferative disabled lymphocytes that lack antigen-specific responses. The development of T-cell senescence in autoimmune diseases contributes to immunological disorders and disease progression. Senescent T cells lack costimulatory markers with the reduction of T cell receptor repertoire and the uptake of natural killer cell receptors. Senescent T cells exert cytotoxic effects through the expression of perforin, granzymes, tumor necrosis factor, and other molecules without the antigen-presenting process. DNA damage accumulation, telomere damage, and limited DNA repair capacity are important features of senescent T cells. Impaired mitochondrial function and accumulation of reactive oxygen species contribute to T cell senescence. Alleviation of T-cell senescence could provide potential targets for the treatment of autoimmune diseases.
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Affiliation(s)
- Yinyun Lu
- Department of Infectious Diseases, Shaoxing People's Hospital, Shaoxing, China
| | - Yongchun Ruan
- Department of Infectious Diseases, Shaoxing People's Hospital, Shaoxing, China
| | - Pan Hong
- Department of Hematology, Shaoxing People's Hospital, Shaoxing, China
| | - Ke Rui
- Department of Transfusion, Shaoxing People's Hospital, Shaoxing, China
| | - Qi Liu
- Department of Laboratory Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, China.
| | - Shengjun Wang
- Department of Immunology, Jiangsu Key Laboratory of Laboratory Medicine, School of Medicine, Jiangsu University, Zhenjiang, China; Department of Laboratory Medicine, The Affiliated People's Hospital, Jiangsu University, Zhenjiang, China.
| | - Dawei Cui
- The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China.
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5
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Carrasco E, Gómez de Las Heras MM, Gabandé-Rodríguez E, Desdín-Micó G, Aranda JF, Mittelbrunn M. The role of T cells in age-related diseases. Nat Rev Immunol 2021; 22:97-111. [PMID: 34099898 DOI: 10.1038/s41577-021-00557-4] [Citation(s) in RCA: 76] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/22/2021] [Indexed: 12/11/2022]
Abstract
Age-related T cell dysfunction can lead to failure of immune tolerance mechanisms, resulting in aberrant T cell-driven cytokine and cytotoxic responses that ultimately cause tissue damage. In this Review, we discuss the role of T cells in the onset and progression of age-associated conditions, focusing on cardiovascular disorders, metabolic dysfunction, neuroinflammation and defective tissue repair and regeneration. We present different mechanisms by which T cells contribute to inflammageing and might act as modulators of age-associated diseases, including through enhanced pro-inflammatory and cytotoxic activity, defective clearance of senescent cells or regulation of the gut microbiota. Finally, we propose that 'resetting' immune system tolerance or targeting pathogenic T cells could open up new therapeutic opportunities to boost resilience to age-related diseases.
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Affiliation(s)
- Elisa Carrasco
- Departamento de Biología, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain.,Departamento de Biología Molecular, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain
| | - Manuel M Gómez de Las Heras
- Departamento de Biología Molecular, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital 12 de Octubre (i+12), Madrid, Spain
| | - Enrique Gabandé-Rodríguez
- Departamento de Biología Molecular, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital 12 de Octubre (i+12), Madrid, Spain
| | - Gabriela Desdín-Micó
- Departamento de Biología Molecular, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital 12 de Octubre (i+12), Madrid, Spain
| | - Juan Francisco Aranda
- Departamento de Biología Molecular, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain.,Instituto de Investigación Sanitaria del Hospital 12 de Octubre (i+12), Madrid, Spain
| | - Maria Mittelbrunn
- Departamento de Biología Molecular, Facultad de Ciencias (UAM); Centro de Biología Molecular 'Severo Ochoa' (CSIC-UAM), Universidad Autónoma de Madrid, Madrid, Spain. .,Instituto de Investigación Sanitaria del Hospital 12 de Octubre (i+12), Madrid, Spain.
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6
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Li PH, Zhang R, Cheng LQ, Liu JJ, Chen HZ. Metabolic regulation of immune cells in proinflammatory microenvironments and diseases during ageing. Ageing Res Rev 2020; 64:101165. [PMID: 32898718 DOI: 10.1016/j.arr.2020.101165] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 02/07/2023]
Abstract
The process of ageing includes molecular changes within cells and interactions between cells, eventually resulting in age-related diseases. Although various cells (immune cells, parenchymal cells, fibroblasts and endothelial cells) in tissues secrete proinflammatory signals in age-related diseases, immune cells are the major contributors to inflammation. Many studies have emphasized the role of metabolic dysregulation in parenchymal cells in age-related inflammatory diseases. However, few studies have discussed metabolic modifications in immune cells during ageing. In this review, we introduce the metabolic dysregulation of major nutrients (glucose, lipids, and amino acids) within immune cells during ageing, which leads to dysfunctional NAD + metabolism that increases immune cell senescence and leads to the acquisition of the corresponding senescence-associated secretory phenotype (SASP). We then focus on senescent immune cell interactions with parenchymal cells and the extracellular matrix and their involvement in angiogenesis, which lead to proinflammatory microenvironments in tissues and inflammatory diseases at the systemic level. Elucidating the roles of metabolic modifications in immune cells during ageing will provide new insights into the mechanisms of ageing and therapeutic directions for age-related inflammatory diseases.
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Affiliation(s)
- Pei-Heng Li
- Department of Internal Medicine, Peking Union Medical college Hospital, Beijing, China; State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Ran Zhang
- Buck Institute for Research on Ageing, Novato, United States
| | - Li-Qin Cheng
- Department of Microbiology, Tumor and Cell Biology, Centre for Translational Microbiome Research, Karolinska Institutet, Stockholm, Sweden
| | - Jin-Jing Liu
- Department of Rheumatology and Clinical Immunology, Peking Union Medical College Hospital, Beijing, China.
| | - Hou-Zao Chen
- State Key Laboratory of Medical Molecular Biology, Department of Biochemistry and Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
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7
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Fulop T, Larbi A, Hirokawa K, Cohen AA, Witkowski JM. Immunosenescence is both functional/adaptive and dysfunctional/maladaptive. Semin Immunopathol 2020; 42:521-536. [PMID: 32930852 PMCID: PMC7490574 DOI: 10.1007/s00281-020-00818-9] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 08/24/2020] [Indexed: 01/08/2023]
Abstract
Alterations in the immune system with aging are considered to underlie many age-related diseases. However, many elderly individuals remain healthy until even a very advanced age. There is also an increase in numbers of centenarians and their apparent fitness. We should therefore change our unilaterally detrimental consideration of age-related immune changes. Recent data taking into consideration the immunobiography concept may allow for meaningful distinctions among various aging trajectories. This implies that the aging immune system has a homeodynamic characteristic balanced between adaptive and maladaptive aspects. The survival and health of an individual depends from the equilibrium of this balance. In this article, we highlight which parts of the aging of the immune system may be considered adaptive in contrast to those that may be maladaptive.
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Affiliation(s)
- T Fulop
- Department of Geriatrics, Faculty of Medicine, Research Center on Aging, University of Sherbrooke, Sherbrooke, QC, J1K 2R1, Canada.
- Research Center on Aging, Faculty of Medicine and Health Sciences, University of Sherbrooke, 3001, 12th Avenue North, Sherbrooke, Quebec, J1H 5N4, Canada.
| | - A Larbi
- Biology of Aging Program and Immunomonitoring Platform, Singapore Immunology Network (SIgN), Agency for Science Technology and Research (A*STAR), Immunos Building, Biopolis, Singapore, 138648, Singapore
| | - K Hirokawa
- Institute of Health and Life Science, Tokyo and Nito-memory Nakanosogo Hospital, Department of Pathology, Tokyo Med. Dent. University, Tokyo, Japan
| | - A A Cohen
- Department of Family Medicine, Faculty of Medicine, Research Center on Aging, University of Sherbrooke, Sherbrooke, QC, J1K 2R1, Canada
| | - J M Witkowski
- Department of Pathophysiology, Medical University of Gdansk, Gdansk, Poland
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Witkowski JM, Bryl E, Fulop T. Should we Try to Alleviate Immunosenescence and Inflammaging - Why, How and to What Extent? Curr Pharm Des 2020; 25:4154-4162. [PMID: 31713479 DOI: 10.2174/1381612825666191111153016] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 11/07/2019] [Indexed: 12/29/2022]
Abstract
With advancing age, immune responses of human beings to external pathogens, i.e., bacteria, viruses, fungi and parasites, and to internal pathogens - malignant neoplasm cells - become less effective. Two major features in the process of aging of the human immune system are immunosenescence and inflammaging. The immune systems of our predecessors co-evolved with pathogens, which led to the occurrence of effective immunity. However, the otherwise beneficial activity may pose problems to the organism of the host and so it has builtin brakes (regulatory immune cells) and - with age - it undergoes adaptations and modifications, examples of which are the mentioned inflammaging and immunosenescence. Here we describe the mechanisms that first created our immune systems, then the consequences of their changes associated with aging, and the mechanisms of inflammaging and immunosenescence. Finally, we discuss to what extent both processes are detrimental and to what extent they might be beneficial and propose some therapeutic approaches for their wise control.
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Affiliation(s)
- Jacek M Witkowski
- Department of Pathophysiology, Medical University of Gdansk, Gdansk, Poland
| | - Ewa Bryl
- Department of Pathology and Experimental Rheumatology, Medical University of Gdansk, Gdansk, Poland
| | - Tamas Fulop
- Research Center on Aging, Faculty of Medicine and Health Sciences, Department of Medicine, University of Sherbrooke, Sherbrooke, Quebec, Canada
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9
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Salminen A. Activation of immunosuppressive network in the aging process. Ageing Res Rev 2020; 57:100998. [PMID: 31838128 DOI: 10.1016/j.arr.2019.100998] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 11/29/2019] [Accepted: 12/09/2019] [Indexed: 12/19/2022]
Abstract
Chronic low-grade inflammation has a key role in the aging process, a state called inflammaging. It is known that the chronic inflammatory condition generates counteracting immunosuppressive state in many diseases. Inflammaging is also associated with an immune deficiency; generally termed as immunosenescence, although it is not known whether it represents the senescence of immune cells or the active remodeling of immune system. Evidence has accumulated since the 1970's indicating that immunosenescence might be caused by an increased activity of immunosuppressive cells rather than cellular senescence. Immune cells display remarkable plasticity; many of these cells can express both proinflammatory and immunosuppressive phenotypes in a context-dependent manner. The immunosuppressive network involves the regulatory subtypes of T (Treg) and B (Breg) cells as well as regulatory phenotypes of macrophages (Mreg), dendritic (DCreg), natural killer (NKreg), and type II natural killer T (NKT) cells. The immunosuppressive network also includes monocytic (M-MDSC) and polymorphonuclear (PMN-MDSC) myeloid-derived suppressor cells which are immature myeloid cells induced by inflammatory mediators. This co-operative network is stimulated in chronic inflammatory conditions preventing excessive inflammatory responses but at the same time they exert harmful effects on the immune system and tissue homeostasis. Recent studies have revealed that the aging process is associated with the activation of immunosuppressive network, especially the functions of MDSCs, Tregs, and Mregs are increased. I will briefly review the properties of the regulatory phenotypes of immune cells and examine in detail the evidences for an activation of immunosuppressive network with aging.
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10
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Salminen A, Kaarniranta K, Kauppinen A. Immunosenescence: the potential role of myeloid-derived suppressor cells (MDSC) in age-related immune deficiency. Cell Mol Life Sci 2019; 76:1901-1918. [PMID: 30788516 PMCID: PMC6478639 DOI: 10.1007/s00018-019-03048-x] [Citation(s) in RCA: 100] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 01/25/2019] [Accepted: 02/14/2019] [Indexed: 12/17/2022]
Abstract
The aging process is associated with chronic low-grade inflammation in both humans and rodents, commonly called inflammaging. At the same time, there is a gradual decline in the functional capacity of adaptive and innate immune systems, i.e., immunosenescence, a process not only linked to the aging process, but also encountered in several pathological conditions involving chronic inflammation. The hallmarks of immunosenescence include a decline in the numbers of naïve CD4+ and CD8+ T cells, an imbalance in the T cell subsets, and a decrease in T cell receptor (TCR) repertoire and signaling. Correspondingly, there is a decline in B cell lymphopoiesis and a reduction in antibody production. The age-related changes are not as profound in innate immunity as they are in adaptive immunity. However, there are distinct functional deficiencies in dendritic cells, natural killer cells, and monocytes/macrophages with aging. Interestingly, the immunosuppression induced by myeloid-derived suppressor cells (MDSC) in diverse inflammatory conditions also targets mainly the T and B cell compartments, i.e., inducing very similar alterations to those present in immunosenescence. Here, we will compare the immune profiles induced by immunosenescence and the MDSC-driven immunosuppression. Given that the appearance of MDSCs significantly increases with aging and MDSCs are the enhancers of other immunosuppressive cells, e.g., regulatory T cells (Tregs) and B cells (Bregs), it seems likely that MDSCs might remodel the immune system, thus preventing excessive inflammation with aging. We propose that MDSCs are potent inducers of immunosenescence.
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Affiliation(s)
- Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland.
| | - Kai Kaarniranta
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland
- Department of Ophthalmology, Kuopio University Hospital, KYS, P.O. Box 100, 70029, Kuopio, Finland
| | - Anu Kauppinen
- School of Pharmacy, Faculty of Health Sciences, University of Eastern Finland, P.O. Box 1627, 70211, Kuopio, Finland
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