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O'Bryan JM, Potts JA, Bonkovsky HL, Mathew A, Rothman AL. Extended interferon-alpha therapy accelerates telomere length loss in human peripheral blood T lymphocytes. PLoS One 2011; 6:e20922. [PMID: 21829595 PMCID: PMC3150344 DOI: 10.1371/journal.pone.0020922] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Accepted: 05/15/2011] [Indexed: 02/07/2023] Open
Abstract
Background Type I interferons have pleiotropic effects on host cells, including inhibiting telomerase in lymphocytes and antiviral activity. We tested the hypothesis that long-term interferon treatment would result in significant reduction in average telomere length in peripheral blood T lymphocytes. Methods/Principal Findings Using a flow cytometry-based telomere length assay on peripheral blood mononuclear cell samples from the Hepatitis-C Antiviral Long-term Treatment against Cirrhosis (HALT-C) study, we measured T cell telomere lengths at screening and at months 21 and 45 in 29 Hepatitis-C virus infected subjects. These subjects had failed to achieve a sustained virologic response following 24 weeks of pegylated-interferon-alpha plus ribavirin treatment and were subsequently randomized to either a no additional therapy group or a maintenance dose pegylated-IFNα group for an additional 3.5 years. Significant telomere loss in naïve T cells occurred in the first 21 months in the interferon-alpha group. Telomere losses were similar in both groups during the final two years. Expansion of CD8+CD45RA+CD57+ memory T cells and an inverse correlation of alanine aminotransferase levels with naïve CD8+ T cell telomere loss were observed in the control group but not in the interferon-alpha group. Telomere length at screening inversely correlated with Hepatitis-C viral load and body mass index. Conclusions/Significance Sustained interferon-alpha treatment increased telomere loss in naïve T cells, and inhibited the accumulation of T cell memory expansions. The durability of this effect and consequences for immune senescence need to be defined.
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Affiliation(s)
- Joel M. O'Bryan
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - James A. Potts
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Herbert L. Bonkovsky
- Department of Medicine, University of Connecticut Health Center, Farmington, Connecticut, United States of America
- Carolinas Medical Center, Charlotte, North Carolina, United States of America
| | - Anuja Mathew
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- * E-mail:
| | - Alan L. Rothman
- Department of Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Institute for Immunology and Informatics, University of Rhode Island, Providence, Rhode Island, United States of America
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Laggner U, Di Meglio P, Perera GK, Hundhausen C, Lacy KE, Ali N, Smith CH, Hayday AC, Nickoloff BJ, Nestle FO. Identification of a novel proinflammatory human skin-homing Vγ9Vδ2 T cell subset with a potential role in psoriasis. THE JOURNAL OF IMMUNOLOGY 2011; 187:2783-93. [PMID: 21813772 DOI: 10.4049/jimmunol.1100804] [Citation(s) in RCA: 261] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
γδ T cells mediate rapid tissue responses in murine skin and participate in cutaneous immune regulation including protection against cancer. The role of human γδ cells in cutaneous homeostasis and pathology is characterized poorly. In this study, we show in vivo evidence that human blood contains a distinct subset of proinflammatory cutaneous lymphocyte Ag and CCR6-positive Vγ9Vδ2 T cells, which is rapidly recruited into perturbed human skin. Vγ9Vδ2 T cells produced an array of proinflammatory mediators including IL-17A and activated keratinocytes in a TNF-α- and IFN-γ-dependent manner. Examination of the common inflammatory skin disease psoriasis revealed a striking reduction of circulating Vγ9Vδ2 T cells in psoriasis patients compared with healthy controls and atopic dermatitis patients. Decreased numbers of circulating Vγ9Vδ2 T cells normalized after successful treatment with psoriasis-targeted therapy. Taken together with the increased presence of Vγ9Vδ2 T cells in psoriatic skin, these data indicate redistribution of Vγ9Vδ2 T cells from the blood to the skin compartment in psoriasis. In summary, we report a novel human proinflammatory γδ T cell involved in skin immune surveillance with immediate response characteristics and with potential clinical relevance in inflammatory skin disease.
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Affiliation(s)
- Ute Laggner
- Cutaneous Medicine and Immunotherapy Unit, St. John's Institute of Dermatology, King's College London, London SE1 9RT, United Kingdom
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Di Mitri D, Azevedo RI, Henson SM, Libri V, Riddell NE, Macaulay R, Kipling D, Soares MVD, Battistini L, Akbar AN. Reversible Senescence in Human CD4+CD45RA+CD27− Memory T Cells. THE JOURNAL OF IMMUNOLOGY 2011; 187:2093-100. [DOI: 10.4049/jimmunol.1100978] [Citation(s) in RCA: 165] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Vukmanovic-Stejic M, Rustin MHA, Nikolich-Zugich J, Akbar AN. Immune responses in the skin in old age. Curr Opin Immunol 2011; 23:525-31. [PMID: 21703840 DOI: 10.1016/j.coi.2011.05.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 05/25/2011] [Accepted: 05/26/2011] [Indexed: 01/05/2023]
Abstract
A marked increase in the susceptibility to cutaneous infections and malignancies has been observed in older humans indicating that cutaneous immunity becomes defective with age. In this review we will focus on recent developments in the understanding of age-related changes in immune function of the skin with a particular emphasis on how alterations in the interaction between cells involved in innate and adaptive immunity leads to decreased cutaneous antigen-specific T cell immunosurveillance.
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Affiliation(s)
- Milica Vukmanovic-Stejic
- Division of Infection and Immunity, Department of Immunology, University College London, London W1T 4JF, United Kingdom
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55
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Are senescence and exhaustion intertwined or unrelated processes that compromise immunity? Nat Rev Immunol 2011; 11:289-95. [PMID: 21436838 DOI: 10.1038/nri2959] [Citation(s) in RCA: 301] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Can the immune system be reactivated continuously throughout the lifetime of an organism or is there a finite point at which repeated antigenic challenge leads to the loss of lymphocyte function or the cells themselves or both? Replicative senescence and exhaustion are processes that control T cell proliferative activity and function; however, there is considerable confusion over the relationship between these two intrinsic cellular control mechanisms. In this Opinion article, we compare the molecular regulation of senescence and exhaustion in T cells. Available data suggest that both processes are regulated independently of each other and that it may be safer to block exhaustion than senescence to enhance immunity.
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56
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Barsov EV. Telomerase and primary T cells: biology and immortalization for adoptive immunotherapy. Immunotherapy 2011; 3:407-21. [PMID: 21395382 PMCID: PMC3120014 DOI: 10.2217/imt.10.107] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Telomeres are specialized repeats, present at the end of chromosomes, whose loss during cell division is followed by growth arrest, a central mechanism of replicative senescence in human cells. Telomere length in stem cells is maintained by telomerase, a specialized reverse transcriptase, whose function is to restore shortening telomeres. Unlike most somatic cell types, human T lymphocytes are capable of briefly reactivating telomerase expression at the time of stimulation. Telomerase expression in T lymphocytes is modulated by a variety of external stimuli and by viral infections. However, telomerase reactivation in stimulated, proliferating human T lymphocytes is limited and cannot prevent the ultimate onset of senescence. Ectopic telomerase expression can rescue human and macaque antigen-specific T cells from senescence. Primary T cells have been engineered with telomerase to have substantially extended replicative lifespans without the loss of primary cell functions or malignant transformation. 'Immortal' antigen-specific T-cell lines and clones overexpressing telomerase are an invaluable source of well-characterized quasi-primary T cells for research of T-cell biology and are potentially useful for immunotherapy of cancer and AIDS.
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Affiliation(s)
- Eugene V Barsov
- SAIC-Frederick, Inc., National Cancer Institute-Frederick, Frederick, MD 21702, USA.
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Libri V, Azevedo RI, Jackson SE, Di Mitri D, Lachmann R, Fuhrmann S, Vukmanovic-Stejic M, Yong K, Battistini L, Kern F, Soares MVD, Akbar AN. Cytomegalovirus infection induces the accumulation of short-lived, multifunctional CD4+CD45RA+CD27+ T cells: the potential involvement of interleukin-7 in this process. Immunology 2011; 132:326-39. [PMID: 21214539 DOI: 10.1111/j.1365-2567.2010.03386.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The relative roles that ageing and lifelong cytomegalovirus (CMV) infection have in shaping naive and memory CD4+ T-cell repertoires in healthy older people is unclear. Using multiple linear regression analysis we found that age itself is a stronger predictor than CMV seropositivity for the decrease in CD45RA+ CD27+ CD4+ T cells over time. In contrast, the increase in CD45RA⁻ CD27⁻ and CD45RA+ CD27⁻ CD4+ T cells is almost exclusively the result of CMV seropositivity, with age alone having no significant effect. Furthermore, the majority of the CD45RA⁻ CD27⁻ and CD45RA+ CD27⁻ CD4+ T cells in CMV-seropositive donors are specific for this virus. CD45RA+ CD27⁻ CD4+ T cells have significantly reduced CD28, interleukin-7 receptor α (IL-7Rα) and Bcl-2 expression, Akt (ser473) phosphorylation and reduced ability to survive after T-cell receptor activation compared with the other T-cell subsets in the same donors. Despite this, the CD45RA+ CD27⁻ subset is as multifunctional as the CD45RA⁻ D27+ and CD45RA⁻ CD27⁻ CD4+ T-cell subsets, indicating that they are not an exhausted population. In addition, CD45RA+ CD27⁻ CD4+ T cells have cytotoxic potential as they express high levels of granzyme B and perforin. CD4+ memory T cells re-expressing CD45RA can be generated from the CD45RA⁻ CD27+ population by the addition of IL-7 and during this process these cells down-regulated expression of IL-7R and Bcl-2 and so resemble their counterparts in vivo. Finally we showed that the proportion of CD45RA+ CD27⁻ CD4+ T cells of multiple specificities was significantly higher in the bone marrow than the blood of the same individuals, suggesting that this may be a site where these cells are generated.
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Affiliation(s)
- Valentina Libri
- Division of Infection and Immunity, University College London, London, UK
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58
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Pandya JM, Fasth AER, Zong M, Arnardottir S, Dani L, Lindroos E, Malmström V, Lundberg IE. Expanded T cell receptor Vβ-restricted T cells from patients with sporadic inclusion body myositis are proinflammatory and cytotoxic CD28null T cells. ACTA ACUST UNITED AC 2010; 62:3457-66. [PMID: 20662057 DOI: 10.1002/art.27665] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Sporadic inclusion body myositis (IBM) is characterized by T cell infiltrates in muscle tissue, but their functional role is unclear. Systemic signs of inflammation are lacking, and the absence of beneficial effects following immunosuppression has challenged the notion of a role for the immune system. This study was undertaken to investigate the phenotype and functionality of T cells, specifically a subset of proinflammatory, cytotoxic, and apoptosis-resistant T cells defined as CD28(null) T cells, in the pathogenesis of sporadic IBM. METHODS A cohort of 27 patients with sporadic IBM was analyzed for the frequency of circulating and muscle-infiltrating CD28(null) T cells. The T cell receptor (TCR) V(β) usage was determined using flow cytometry and immunohistochemistry. Anti-CD3-stimulated peripheral blood mononuclear cells were analyzed for intracellular interferon-γ and cytotoxic potential by flow cytometry. RESULTS We found striking accumulations of both CD8+CD28(null) and CD4+CD28(null) T cells, which represented the TCR V(β) -expanded T cells in sporadic IBM. Such CD28(null) T cells were abundant both in the inflamed muscle tissue and in the circulation. Although the specific TCR V(β) expansions varied between patients, both CD8+CD28(null) and CD4+CD28(null) T cells consistently displayed a highly proinflammatory and cytotoxic potential. CONCLUSION Our results suggest that CD28null T cell expansions represent the previously described expanded T cell subsets in sporadic IBM, and their proinflammatory capacity and presence in both muscle tissue and the circulation may imply a role of immune activation in sporadic IBM. In addition, CD4+CD28(null) T cells may exert cytotoxic effects directly on muscle fibers due to a cytotoxic potential similar to that in CD8+ T cells.
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Affiliation(s)
- Jayesh M Pandya
- Rheumatology Unit, Karolinska University Hospital, Stockholm, Sweden.
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Hoare M, Gelson WT, Das A, Fletcher JM, Davies SE, Curran MD, Vowler SL, Maini MK, Akbar AN, Alexander GJ. CD4+ T-lymphocyte telomere length is related to fibrosis stage, clinical outcome and treatment response in chronic hepatitis C virus infection. J Hepatol 2010; 53:252-60. [PMID: 20462651 PMCID: PMC2913243 DOI: 10.1016/j.jhep.2010.03.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Revised: 02/04/2010] [Accepted: 03/03/2010] [Indexed: 12/26/2022]
Abstract
BACKGROUND & AIMS Increasing age is associated with impaired immune function and in chronic HCV infection specifically, with progressive fibrosis, liver failure, HCC and impaired responses to antiviral therapy. T-lymphocyte telomere length declines with age. We hypothesised that shorter T-lymphocyte telomere length would be associated with poor clinical outcome in HCV infection. METHODS Circulating T-lymphocyte telomere length, an objective measure of immune senescence, was measured by flow-FISH in 135 HCV-RNA-positive, treatment-naïve patients and 41 healthy controls in relation to clinical outcome. RESULTS Shorter CD4+CD45RO+ T-lymphocyte telomeres were associated with severe fibrosis (p=0.003), independent of male sex (p=0.04), CMV positivity (p=0.003), previous HBV infection (p=0.007), and age (p=ns) in viraemic patients compared to controls. There were inverse correlations between CD4+CD45RO+ telomere length and fibrosis stage (p<0.001), portal tract inflammatory grade (p=0.035), prothrombin time (p<0.001) and bilirubin (p=0.001). One hundred and twenty-four viraemic individuals were followed prospectively to a composite endpoint of death, hepatic decompensation or HCC. Independent of age, those with shorter CD4+CD45RO+ telomeres were less likely to be complication free after 2-years than those with longer telomeres (86% versus 96%, p=0.009) with an age-adjusted hazard ratio of 0.93 (0.90-0.96). In addition, CD4+CD45RO+ telomere length predicted successful antiviral therapy (p=0.001) independent of other factors. CONCLUSIONS CD4+ T-lymphocyte telomere length, independent of age, was related to inflammatory grade, fibrosis stage, laboratory indices of severity, subsequent hepatic decompensation and treatment outcome in patients with chronic HCV infection.
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Key Words
- hcv, hepatitis c virus
- hcc, hepatocellular carcinoma
- cmv, cytomegalovirus
- hbv, hepatitis b virus
- ebv, epstein–barr virus
- hiv, human immunodeficiency virus
- ifn-α, interferon-α
- pbmcs, peripheral blood mononuclear cells
- apcs, antigen presenting cells
- hr, hazard ratio
- hepatitis c
- telomere
- t-lymphocyte
- immune senescence
- human
- ageing
- hepatocellular carcinoma
- outcome study
- interferon-α
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Affiliation(s)
- Matthew Hoare
- Department of Medicine, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - William T.H. Gelson
- Department of Medicine, School of Clinical Medicine, University of Cambridge, Cambridge, UK
| | - Abhi Das
- Department of Immunology, University College London, London, UK
| | | | - Susan E. Davies
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Martin D. Curran
- Clinical Microbiology and Public Health Laboratory, Health Protection Agency, Addenbrooke’s Hospital, Cambridge, UK
| | - Sarah L. Vowler
- Centre for Applied Medical Statistics, Department of Public Health and Primary Care, University of Cambridge, Institute of Public Health, Forvie Site, Robinson Way, Cambridge, UK
| | - Mala K. Maini
- Department of Immunology, University College London, London, UK
| | - Arne N. Akbar
- Department of Immunology, University College London, London, UK
| | - Graeme J.M. Alexander
- Department of Medicine, School of Clinical Medicine, University of Cambridge, Cambridge, UK,Corresponding author. Address: Department of Medicine, Box 157, Addenbrooke’s Hospital, Hills Road, Cambridge CB2 2QQ, UK. Tel.: +44 1223 336008; fax: +44 1223 216111.
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Liu JP, Chen SM, Cong YS, Nicholls C, Zhou SF, Tao ZZ, Li H. Regulation of telomerase activity by apparently opposing elements. Ageing Res Rev 2010; 9:245-56. [PMID: 20362078 DOI: 10.1016/j.arr.2010.03.002] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2010] [Revised: 03/22/2010] [Accepted: 03/23/2010] [Indexed: 01/08/2023]
Abstract
Telomeres, the ends of chromosomes, undergo frequent remodeling events that are important in cell development, proliferation and differentiation, and neoplastic immortalization. It is not known how the cellular environment influences telomere remodeling, stability, and lengthening or shortening. Telomerase is a ribonucleoprotein complex that maintains and lengthens telomeres in the majority of cancers. Recent studies indicate that a number of factors, including hormones, cytokines, ligands of nuclear receptor, vitamins and herbal extracts have significantly influence telomerase activity and, in some instances, the remodeling of telomeres. This review summarizes the advances in understanding of the positive and negative regulation by extracellular factors of telomerase activity in cancer, stem cells and other systems in mammals.
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Affiliation(s)
- Jun-Ping Liu
- Molecular Signaling Laboratory, Department of Immunology, Central Clinical School, Monash University, Alfred Medical Research and Education Precinct (AMREP), Commercial Road, Melbourne, Victoria 3004, Australia
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61
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Henson SM, Akbar AN. Memory T-Cell Homeostasis and Senescence during Aging. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2010; 684:189-97. [DOI: 10.1007/978-1-4419-6451-9_15] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Andrews NP, Fujii H, Goronzy JJ, Weyand CM. Telomeres and immunological diseases of aging. Gerontology 2009; 56:390-403. [PMID: 20016137 DOI: 10.1159/000268620] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Accepted: 09/07/2009] [Indexed: 12/14/2022] Open
Abstract
A defining feature of the eukaryotic genome is the presence of linear chromosomes. This arrangement, however, poses several challenges with regard to chromosomal replication and maintenance. To prevent the loss of coding sequences and to suppress gross chromosomal rearrangements, linear chromosomes are capped by repetitive nucleoprotein structures, called telomeres. Each cell division results in a progressive shortening of telomeres that, below a certain threshold, promotes genome instability, senescence, and apoptosis. Telomeric erosion, maintenance, and repair take center stage in determining cell fate. Cells of the immune system are under enormous proliferative demand, stressing telomeric intactness. Lymphocytes are capable of upregulating telomerase, an enzyme that can elongate telomeric sequences and, thus, prolong cellular lifespan. Therefore, telomere dynamics are critical in preserving immune function and have become a focus for studies of immunosenescence and autoimmunity. In this review, we describe the role of telomeric nucleoproteins in shaping telomere architecture and in suppressing DNA damage responses. We summarize new insights into the regulation of telomerase activity, hereditary disorders associated with telomere dysfunction, the role of telomere loss in immune aging, and the impact of telomere dysfunction in chronic inflammatory disease.
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Affiliation(s)
- Nicolas P Andrews
- Lowance Center for Human Immunology, Department of Medicine, Emory University School of Medicine, Atlanta, GA 30322, USA
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63
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Ferrara G, Losi M, Fabbri LM, Migliori GB, Richeldi L, Casali L. Exploring the immune response against Mycobacterium tuberculosis for a better diagnosis of the infection. Arch Immunol Ther Exp (Warsz) 2009; 57:425-33. [PMID: 19866341 DOI: 10.1007/s00005-009-0050-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2009] [Accepted: 04/29/2009] [Indexed: 01/18/2023]
Abstract
Tuberculosis (TB) still represents a monumental problem, with more than two million deaths every year worldwide. The current diagnostics for TB offer sub-optimal accuracy both for the active and the latent form of infection and are often based on technologies unaffordable in low-income settings. The tuberculin skin test was the first diagnostic based on an acquired immune response towards Mycobacterium tuberculosis (MTB). Advances in molecular and cellular biology and the elucidation of the mechanisms governing the relation between MTB and the human immune system form the basis for new and more accurate assays, potentially able to fill the gaps and limits of classical diagnostics. However, the process of validating new tests is still complex and hampered by specific questions regarding TB immunology and natural history. We present here a summary of the current approaches to validate new diagnostics based on the detection of immunological biomarkers of TB infection.
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Affiliation(s)
- Giovanni Ferrara
- Section of Respiratory Disease, Department of Internal Medicine, St. Maria Hospital, University of Perugia, Via T. Di Joannuccio 1, 05100 Terni, Italy.
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Haanstra KG, Endell J, Estévâo D, Kondova I, Jonker M. Blocking T cell co-stimulation using a CD80 blocking small molecule reduces delayed type hypersensitivity responses in rhesus monkeys. Clin Exp Immunol 2009; 158:91-8. [PMID: 19737235 DOI: 10.1111/j.1365-2249.2009.03994.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Blockade of co-stimulation signals between T cells and antigen-presenting cells could be an important approach for treatment of autoimmune diseases and transplant rejection. Recently a series of small compound inhibitors which bind human CD80 (B7-1) and inhibit T cell co-stimulation has been described. To investigate their potency for clinical use, one of these compounds, RhuDex, was evaluated for reactivity with rhesus monkey CD80. The in vitro biological effect on rhesus monkey lymphocytes, the potency for suppression of an inflammatory recall response and the protein-induced delayed type hypersensitivity (DTH) response in the skin were studied. In a rhesus monkey T cell co-stimulation assay RhuDex inhibited proinflammatory cytokine release and cellular proliferation with micromolar potency. Systemic administration of RhuDex to rhesus monkeys inhibited the DTH response significantly, indicating that this compound may inhibit autoimmune mediated inflammatory processes where the target, CD80, is up-regulated.
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Affiliation(s)
- K G Haanstra
- Biomedical Primate Research Centre, Rijswijk, the Netherlands.
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65
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Agius E, Lacy KE, Vukmanovic-Stejic M, Jagger AL, Papageorgiou AP, Hall S, Reed JR, Curnow SJ, Fuentes-Duculan J, Buckley CD, Salmon M, Taams LS, Krueger J, Greenwood J, Klein N, Rustin MHA, Akbar AN. Decreased TNF-alpha synthesis by macrophages restricts cutaneous immunosurveillance by memory CD4+ T cells during aging. ACTA ACUST UNITED AC 2009; 206:1929-40. [PMID: 19667063 PMCID: PMC2737169 DOI: 10.1084/jem.20090896] [Citation(s) in RCA: 140] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Immunity declines during aging, however the mechanisms involved in this decline are not known. In this study, we show that cutaneous delayed type hypersensitivity (DTH) responses to recall antigens are significantly decreased in older individuals. However, this is not related to CC chemokine receptor 4, cutaneous lymphocyte-associated antigen, or CD11a expression by CD4+ T cells or their physical capacity for migration. Instead, there is defective activation of dermal blood vessels in older subject that results from decreased TNF-α secretion by macrophages. This prevents memory T cell entry into the skin after antigen challenge. However, isolated cutaneous macrophages from these subjects can be induced to secrete TNF-α after stimulation with Toll-like receptor (TLR) 1/2 or TLR 4 ligands in vitro, indicating that the defect is reversible. The decreased conditioning of tissue microenvironments by macrophage-derived cytokines may therefore lead to defective immunosurveillance by memory T cells. This may be a predisposing factor for the development of malignancy and infection in the skin during aging.
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Affiliation(s)
- Elaine Agius
- Department of Immunology, Division of Infection and Immunity, University College London, London, W1T 4JF, England, UK
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KLRG1 signaling induces defective Akt (ser473) phosphorylation and proliferative dysfunction of highly differentiated CD8+ T cells. Blood 2009; 113:6619-28. [PMID: 19406987 DOI: 10.1182/blood-2009-01-199588] [Citation(s) in RCA: 183] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Highly differentiated CD8+CD28-CD27- T cells have short telomeres, defective telomerase activity, and reduced capacity for proliferation, indicating that they are close to replicative senescence. In addition, these cells express increased levels of the senescence-associated inhibitory receptor KLRG1 and have poor capacity for IL-2 synthesis and defective Akt (ser(473)) phosphorylation after activation. It is not known whether signaling via KLRG1 contributes to any of the attenuated differentiation-related functional changes in CD8+ T cells. To address this, we blocked KLRG1 signaling during T-cell receptor activation using antibodies against its major ligand, E-cadherin. This resulted in a significant enhancement of Akt (ser(473)) phosphorylation and T-cell receptor-induced proliferative activity of CD8+CD28-CD27- T cells. Furthermore, the increase of proliferation was directly linked to the Akt-mediated induction of cyclin D and E and reduction in the cyclin inhibitor p27 expression. In contrast, the reduced telomerase activity in highly differentiated CD8+CD28(-)CD27- T cells was not altered by KLRG1 blockade, indicating the involvement of other mechanisms. This is the first demonstration of a functional role for KLRG1 in primary human CD8+ T cells and highlights that certain functional defects that arise during progressive T-cell differentiation toward replicative senescence are maintained actively by inhibitory receptor signaling.
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Abstract
In rheumatoid arthritis (RA), chronically stimulated T lymphocytes sustain tissue-destructive joint inflammation. Both naïve and memory T cells in RA are prematurely aged with accelerated loss of telomeres suggesting excessive proliferative pressure or inadequate telomeric maintenance. Upon stimulation, RA naïve CD4 T cells are defective in up-regulating telomerase activity (P < 0.0001) due to insufficient induction of the telomerase component human telomerase reverse transcriptase (hTERT); T cell activation and cell cycle progression are intact. Telomerase insufficiency does not affect memory T cells or CD34 hematopoietic stem cells and is present in untreated patients and independent from disease activity. Knockdown of hTERT in primary human T cells increases apoptotic propensity (P = 0.00005) and limits clonal burst (P = 0.0001) revealing a direct involvement of telomerase in T cell fate decisions. Naïve RA CD4 T cells stimulated through the T cell receptor are highly susceptible to apoptosis, expanding to smaller clonal size. Overexpression of ectopic hTERT in naïve RA T cells conveys apoptotic resistance (P = 0.008) and restores proliferative expansion (P < 0.0001). Telomerase insufficiency in RA results in excessive T cell loss, undermining homeostatic control of the naive T cell compartment and setting the stage for lymphopenia-induced T cell repertoire remodeling. Restoring defective telomerase activity emerges as a therapeutic target in resetting immune abnormalities in RA.
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Zachos I, Konstantinopoulos PA, Vandoros GP, Karamouzis MV, Papatsoris AG, Podimatas T, Papachristodoulou A, Chrisofos M, Deliveliotis C, Papavassiliou AG. Predictive value of telomerase reverse transcriptase expression in patients with high risk superficial bladder cancer treated with adjuvant BCG immunotherapy. J Cancer Res Clin Oncol 2009; 135:1169-75. [PMID: 19214569 DOI: 10.1007/s00432-009-0557-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2008] [Accepted: 01/26/2009] [Indexed: 10/21/2022]
Abstract
PURPOSE We conducted a prospective study to determine whether expression of telomerase reverse transcriptase (hTERT) is associated with recurrence-free-survival (RFS) or development of invasive disease in patients with high risk superficial bladder cancer (SBC) that received adjuvant BCG immunotherapy. METHODS Thirty patients with high-grade T1 tumors were evaluated. Pre-BCG TURBT and post-BCG specimens were analyzed for hTERT nucleolar expression by immunohistochemistry. RESULTS Post-BCG hTERT expression was statistically significantly lower than pre-BCG hTERT expression. Pre-BCG hTERT nucleolar staining in more than 75% of cells was associated with worse RFS (9 months vs. not yet reached, P = 0.05), while post-BCG hTERT nucleolar staining in more than 50% of the cells was associated with worse RFS (6 months vs. not yet reached, P = 0.001) and development of invasive disease. In multivariate analysis, post-BCG hTERT expression was independently associated with RFS and development of invasive disease. CONCLUSIONS Immunohistochemical evaluation of hTERT may help define a subset of high risk SBC patients that will eventually fail BCG and may therefore benefit from early salvage cystectomy.
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Affiliation(s)
- Ioannis Zachos
- Department of Urology, University of Thessalia, Larissa, Greece
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69
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Fuhrmann S, Streitz M, Kern F. How flow cytometry is changing the study of TB immunology and clinical diagnosis. Cytometry A 2008; 73:1100-6. [PMID: 18688843 DOI: 10.1002/cyto.a.20614] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The application of flow cytometry has hugely advanced the field of tuberculosis (TB) across all areas of research ranging from diagnostic tests to understanding the underlying immunology. As cellular responses are understood to be the mainstay of the immune response in the control of TB it is very likely that polychromatic flow will become the tool of choice for assessing the effects of vaccination. Results are particularly encouraging in this area. The development of a new type of diagnostic test, a prototype of which has been reported, may be the spin-off of a broad and systematic approach to understanding and profiling the T-cell response to TB. It is obvious that flow cytometry will not be able to address all research questions in the field of TB. However, its enormous flexibility as a technology will make it the tool of choice in many situations. An ever increasing availability of flow cytometers, even in resource-poor countries, will rapidly change the face of TB research and management in the years ahead.
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Affiliation(s)
- Stephan Fuhrmann
- Division of Medicine, Brighton and Sussex Medical School, University of Sussex Campus, Brighton BN19PS, United Kingdom
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70
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Vukmanovic-Stejic M, Agius E, Booth N, Dunne PJ, Lacy KE, Reed JR, Sobande TO, Kissane S, Salmon M, Rustin MH, Akbar AN. The kinetics of CD4+Foxp3+ T cell accumulation during a human cutaneous antigen-specific memory response in vivo. J Clin Invest 2008; 118:3639-50. [PMID: 18924611 DOI: 10.1172/jci35834] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2008] [Accepted: 08/20/2008] [Indexed: 12/27/2022] Open
Abstract
Naturally occurring CD4(+)CD25(hi)Foxp3(+) Tregs (nTregs) are highly proliferative in blood. However, the kinetics of their accumulation and proliferation during a localized antigen-specific T cell response is currently unknown. To explore this, we used a human experimental system whereby tuberculin purified protein derivative (PPD) was injected into the skin and the local T cell response analyzed over time. The numbers of both CD4(+)Foxp3(-) (memory) and CD4(+)Foxp3(+) (putative nTreg) T cells increased in parallel, with the 2 populations proliferating at the same relative rate. In contrast to CD4(+)Foxp3(-) T cell populations, skin CD4(+)Foxp3(+) T cells expressed typical Treg markers (i.e., they were CD25(hi), CD127(lo), CD27(+), and CD39(+)) and did not synthesize IL-2 or IFN-gamma after restimulation in vitro, indicating that they were not recently activated effector cells. To determine whether CD4(+)Foxp3(+) T cells in skin could be induced from memory CD4(+) T cells, we expanded skin-derived memory CD4(+) T cells in vitro and anergized them. These cells expressed high levels of CD25 and Foxp3 and suppressed the proliferation of skin-derived responder T cells to PPD challenge. Our data therefore demonstrate that memory and CD4(+) Treg populations are regulated in tandem during a secondary antigenic response. Furthermore, it is possible to isolate effector CD4(+) T cell populations from inflamed tissues and manipulate them to generate Tregs with the potential to suppress inflammatory responses.
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71
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Abstract
Telomeres play a central role in cell fate and aging by adjusting the cellular response to stress and growth stimulation on the basis of previous cell divisions and DNA damage. At least a few hundred nucleotides of telomere repeats must "cap" each chromosome end to avoid activation of DNA repair pathways. Repair of critically short or "uncapped" telomeres by telomerase or recombination is limited in most somatic cells and apoptosis or cellular senescence is triggered when too many "uncapped" telomeres accumulate. The chance of the latter increases as the average telomere length decreases. The average telomere length is set and maintained in cells of the germline which typically express high levels of telomerase. In somatic cells, telomere length is very heterogeneous but typically declines with age, posing a barrier to tumor growth but also contributing to loss of cells with age. Loss of (stem) cells via telomere attrition provides strong selection for abnormal and malignant cells, a process facilitated by the genome instability and aneuploidy triggered by dysfunctional telomeres. The crucial role of telomeres in cell turnover and aging is highlighted by patients with 50% of normal telomerase levels resulting from a mutation in one of the telomerase genes. Short telomeres in such patients are implicated in a variety of disorders including dyskeratosis congenita, aplastic anemia, pulmonary fibrosis, and cancer. Here the role of telomeres and telomerase in human aging and aging-associated diseases is reviewed.
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Affiliation(s)
- Geraldine Aubert
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada
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72
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Almeida CAM, Martin AM, Nolan D, Lucas A, Cameron PU, James I, Phillips E, Mallal S. Cytokine Profiling in Abacavir Hypersensitivity Patients. Antivir Ther 2008. [DOI: 10.1177/135965350801300202] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Background Abacavir hypersensitivity in genetically susceptible individuals implicates an abacavir-specific T-cell response to either the parent drug or a metabolite generated in vivo. We have analysed the cytokine profile in antigen-presenting cells and the T-lymphocytes that are involved in the pathological immune response to abacavir. Methods In this study, we compared abacavir-specific cytokine responses in cultured peripheral blood mononuclear cells (PBMCs) from HIV-infected abacavir hypersensitive, tolerant and naive individuals. Cells were cultured in the presence or absence of abacavir. Cytokine expression was determined by microarray analysis, enzyme-linked immunosorbent assays and flow cytometry. Results We demonstrated using in vitro models of immune activation that the production of interferon-γwas specifically induced by abacavir treatment in PBMCs obtained from hypersensitive patients carrying the HLA-B*5701 allele (median 123.86 compared with -30.83 for tolerant controls, P=0.001). Conclusion These results provide further insight into the immunological and metabolic basis of abacavir hypersensitivity syndrome. In vitro assays could assist in the identification of susceptible loci by providing a surrogate marker for the hypersensitivity reaction. Such a marker could be studied in unexposed individuals to shed further light on the immunopathogenesis of the abacavir hypersensitivity syndrome.
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Affiliation(s)
- Coral-Ann M Almeida
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
| | - Annalise M Martin
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
| | - David Nolan
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
| | - Andrew Lucas
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
| | - Paul U Cameron
- Department of Clinical Immunology and Biochemical Genetics, Royal Perth Hospital, Perth, Australia
| | - Ian James
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
| | - Elizabeth Phillips
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
| | - Simon Mallal
- Centre for Clinical Immunology and Biomedical Statistics, Royal Perth Hospital and Murdoch University, Perth, Australia
- Department of Clinical Immunology and Biochemical Genetics, Royal Perth Hospital, Perth, Australia
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Iancu EM, Speiser DE, Rufer N. Assessing ageing of individual T lymphocytes: mission impossible? Mech Ageing Dev 2007; 129:67-78. [PMID: 18048082 DOI: 10.1016/j.mad.2007.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2007] [Revised: 10/15/2007] [Accepted: 10/23/2007] [Indexed: 12/22/2022]
Abstract
Effector T lymphocytes are the progeny of a limited number of antigen-specific precursor cells and it has been estimated that clonotypic human T cells may expand million fold on their way reaching high cell numbers that are sufficient for immune protection. Moreover, memory T cell responses are characterized by repetitive expansion of antigen-specific T cell clonotypes, and limitations in the proliferative capacity could lead to immune senescence. Because telomeres progressively shorten as a function of cell division, telomere length is a powerful indicator of the replicative in vivo history of human T lymphocytes. In this review, we summarize observations made over the last decade on telomere length dynamics of well-defined T cell populations derived from healthy donors and patients with infectious disease or cancer. We focus on T cell differentiation, T cell ageing, and natural and vaccine induced immune responses. We also discuss the scientific evidence for in vivo replicative senescence of antigen-specific T cells, and evaluate the available methods for measuring telomere lengths and telomerase activity, and their potential and limitations to increase our understanding of T cell physiology.
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Affiliation(s)
- Emanuela M Iancu
- Division of Experimental Oncology, Multidisciplinary Oncology Center CePO, Avenue Pierre-Decker 4, CH-1005 Lausanne, Switzerland
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74
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Plunkett FJ, Franzese O, Finney HM, Fletcher JM, Belaramani LL, Salmon M, Dokal I, Webster D, Lawson ADG, Akbar AN. The loss of telomerase activity in highly differentiated CD8+CD28-CD27- T cells is associated with decreased Akt (Ser473) phosphorylation. THE JOURNAL OF IMMUNOLOGY 2007; 178:7710-9. [PMID: 17548608 DOI: 10.4049/jimmunol.178.12.7710] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The enzyme telomerase is essential for maintaining the replicative capacity of memory T cells. Although CD28 costimulatory signals can up-regulate telomerase activity, human CD8(+) T cells lose CD28 expression after repeated activation. Nevertheless, telomerase is still inducible in CD8(+)CD28(-) T cells. To identify alternative costimulatory pathways that may be involved, we introduced chimeric receptors containing the signaling domains of CD28, CD27, CD137, CD134, and ICOS in series with the CD3 zeta (zeta) chain into primary human CD8(+) T cells. Although CD3 zeta-chain signals alone were ineffective, triggering of all the other constructs induced proliferation and telomerase activity. However, not all CD8(+)CD28(-) T cells could up-regulate this enzyme. The further fractionation of CD8(+)CD28(-) T cells into CD8(+)CD28(-) CD27(+) and CD8(+)CD28(-)CD27(-) subsets showed that the latter had significantly shorter telomeres and extremely poor telomerase activity. The restoration of CD28 signaling in CD8(+)CD28(-)CD27(-) T cells could not reverse the low telomerase activity that was not due to decreased expression of human telomerase reverse transcriptase, the enzyme catalytic subunit. Instead, the defect was associated with decreased phosphorylation of the kinase Akt, that phosphorylates human telomerase reverse transcriptase to induce telomerase activity. Furthermore, the defective Akt phosphorylation in these cells was specific for the Ser(473) but not the Thr(308) phosphorylation site of this molecule. Telomerase down-regulation in highly differentiated CD8(+)CD28(-)CD27(-) T cells marks their inexorable progress toward a replicative end stage after activation. This limits the ability of memory CD8(+) T cells to be maintained by continuous proliferation in vivo.
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Affiliation(s)
- Fiona J Plunkett
- Department of Immunology and Molecular Pathology, University College London, 46 Cleveland Street, London, United Kingdom
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75
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Akbar AN, Vukmanovic-Stejic M. Telomerase in T lymphocytes: use it and lose it? THE JOURNAL OF IMMUNOLOGY 2007; 178:6689-94. [PMID: 17513711 DOI: 10.4049/jimmunol.178.11.6689] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The enzyme telomerase counteracts telomere loss in proliferating cells and extends their capacity for replication. The importance of telomerase is highlighted by the award of the 2006 Albert Lasker Prize for Basic Medical Research for its discovery. Malignant cells subvert telomerase induction to their advantage, and up-regulation of this enzyme confers these populations with unlimited proliferative potential with obvious detrimental consequences. However this enzyme is also essential for the lifelong maintenance of normal cell populations that have a high rate of turnover. Thymic involution in early adulthood dictates that memory T cell populations have to be maintained by continuous proliferation. This highlights the inherent paradox that telomerase down-regulation in T cells may protect against malignancy yet also lead to replicative exhaustion of repeatedly activated memory T cells. In this article, we review the data on telomerase regulation in T lymphocytes and the implications this has for the maintenance of T cell memory.
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Affiliation(s)
- Arne N Akbar
- Department of Immunology and Molecular Pathology, University College London, London, United Kingdom
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76
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Shen X, Zhou J, Hathcock KS, Robbins P, Powell DJ, Rosenberg SA, Hodes RJ. Persistence of tumor infiltrating lymphocytes in adoptive immunotherapy correlates with telomere length. J Immunother 2007; 30:123-9. [PMID: 17198091 PMCID: PMC2151201 DOI: 10.1097/01.cji.0000211321.07654.b8] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Transfer of autologous tumor-specific tumor infiltrating lymphocytes (TILs) in adoptive immunotherapy can mediate the regression of tumor in patients with metastatic melanoma. In this procedure, TILs from resected tumors are expanded in vitro, then administered to patients and further stimulated to proliferate in vivo by the administration of high dose IL-2. After in vitro expansion, TILs are often dominated by a few specific clonotypes, and recently it was reported that the persistence in vivo of one or more of these clonotypes correlated with positive therapeutic response. We and others have previously shown that repeated in vitro stimulation and clonal expansion of normal human T lymphocytes results in progressive decrease in telomerase activity and shortening of telomeres, ultimately resulting in replicative senescence. In the studies reported here, we therefore compared telomerase activity and telomere length in persistent and nonpersistent TIL clonotypes before transfer in vivo, and found a correlation between telomere length and clonal persistence. We also observed that TILs proliferate extensively in vivo in the days after transfer, but fail to induce substantial telomerase activity, and undergo rapid decreases in telomere length within days after transfer. Thus, in vivo loss of telomeres by clonotypes that have the shortest telomeres at the time of administration may drive these clones to replicative senescence, whereas cells with longer telomeres are able to persist and mediate antitumor effects. These findings are relevant both to predicting effectiveness of adoptive immunotherapy and in deriving strategies for improving effectiveness by sustaining telomere length.
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Affiliation(s)
- Xinglei Shen
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Juhua Zhou
- Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Karen S. Hathcock
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Paul Robbins
- Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Daniel J. Powell
- Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Steven A. Rosenberg
- Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
| | - Richard J. Hodes
- Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
- National Institute on Aging, National Institutes of Health, Bethesda, MD 20892
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77
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Zaunders JJ, Dyer WB, Munier ML, Ip S, Liu J, Amyes E, Rawlinson W, De Rose R, Kent SJ, Sullivan JS, Cooper DA, Kelleher AD. CD127+CCR5+CD38+++ CD4+ Th1 effector cells are an early component of the primary immune response to vaccinia virus and precede development of interleukin-2+ memory CD4+ T cells. J Virol 2006; 80:10151-61. [PMID: 17005692 PMCID: PMC1617315 DOI: 10.1128/jvi.02670-05] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
The stages of development of human antigen-specific CD4+ T cells responding to viral infection and their differentiation into long-term memory cells are not well understood. The inoculation of healthy adults with vaccinia virus presents an opportunity to study these events intensively. Between days 11 and 14 postinoculation, there was a peak of proliferating CCR5+CD38+++ CD4+ effector cells which contained the cytotoxic granule marker T-cell intracellular antigen 1 and included gamma interferon (IFN-gamma)-producing vaccinia virus-specific CD4+ T cells. The majority of these initial vaccinia virus-specific CD4+ T cells were CD127+ and produced interleukin-2 (IL-2) but not CTLA-4 in response to restimulation in vitro. Between days 14 and 21, there was a switch from IFN-gamma and IL-2 coexpression to IL-2 production only, coinciding with a resting phenotype and an increased in vitro proliferation response. The early CCR5+CD38+++ vaccinia virus-specific CD4+ T cells were similar to our previous observations of human immunodeficiency virus (HIV)-specific CD4+ T cells in primary HIV type 1 (HIV-1) infection, but the vaccinia virus-specific cells expressed much more CD127 and IL-2 than we previously found in their HIV-specific counterparts. The current study provides important information on the differentiation of IL-2+ vaccinia virus-specific memory cells, allowing further study of antiviral effector CD4+ T cells in healthy adults and their dysfunction in HIV-1 infection.
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Affiliation(s)
- John J Zaunders
- Centre for Immunology, St. Vincent's Hospital, Victoria Street, Darlinghurst, NSW 2010, Australia.
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78
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Vukmanovic-Stejic M, Reed JR, Lacy KE, Rustin MHA, Akbar AN. Mantoux Test as a model for a secondary immune response in humans. Immunol Lett 2006; 107:93-101. [PMID: 16979761 DOI: 10.1016/j.imlet.2006.08.002] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 08/02/2006] [Accepted: 08/04/2006] [Indexed: 12/29/2022]
Abstract
The Mantoux Test (MT) is a classical delayed-type hypersensitivity (DTH) response to the intradermal injection of tuberculin purified protein derivative (PPD). It represents a cutaneous T cell mediated memory recall immune response. The test is typically used to determine immunity to tuberculosis in humans and positive reactions develop in individuals previously exposed to Mycobacterium tuberculosis, and those immunised with the Bacillus of Calmette and Guérin (BCG) vaccine. In view of its relative accessibility human skin represents a convenient tissue for the investigation of human immune responses. Using the MT, we have been able to determine that significant cellular proliferation and clonal expansion occur at the site of antigen deposition in the skin. Furthermore, cells undergoing proliferation in the skin also undergo accelerated differentiation. Taken together with other studies, in humans and in mice, these observations shed new light on the importance of the microenvironment at the site of the immune response for the proliferation and differentiation of memory T cells.
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Affiliation(s)
- Milica Vukmanovic-Stejic
- Department of Immunology and Molecular Pathology, Division of Infection and Immunity, Windeyer Institute of Medical Sciences, University College London, London W1T 4JF, UK.
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79
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Vukmanovic-Stejic M, Zhang Y, Cook JE, Fletcher JM, McQuaid A, Masters JE, Rustin MHA, Taams LS, Beverley PCL, Macallan DC, Akbar AN. Human CD4+ CD25hi Foxp3+ regulatory T cells are derived by rapid turnover of memory populations in vivo. J Clin Invest 2006; 116:2423-33. [PMID: 16955142 PMCID: PMC1555646 DOI: 10.1172/jci28941] [Citation(s) in RCA: 371] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2006] [Accepted: 07/11/2006] [Indexed: 01/01/2023] Open
Abstract
While memory T cells are maintained by continuous turnover, it is not clear how human regulatory CD4+ CD45RO+ CD25hi Foxp3+ T lymphocyte populations persist throughout life. We therefore used deuterium labeling of cycling cells in vivo to determine whether these cells could be replenished by proliferation. We found that CD4+ CD45RO+ Foxp3+ CD25hi T lymphocytes were highly proliferative, with a doubling time of 8 days, compared with memory CD4+ CD45RO+ Foxp3- CD25- (24 days) or naive CD4+ CD45RA+ Foxp3- CD25- populations (199 days). However, the regulatory population was susceptible to apoptosis and had critically short telomeres and low telomerase activity. It was therefore unlikely to be self regenerating. These data are consistent with continuous production from another population source. We found extremely close TCR clonal homology between regulatory and memory CD4+ T cells. Furthermore, antigen-related expansions within certain TCR Vbeta families were associated with parallel numerical increases of CD4+ CD45RO+ CD25hi Foxp3+ Tregs with the same Vbeta usage. It is therefore unlikely that all human CD4+ CD25+ Foxp3+ Tregs are generated as a separate functional lineage in the thymus. Instead, our data suggest that a proportion of this regulatory population is generated from rapidly dividing, highly differentiated memory CD4+ T cells; this has considerable implications for the therapeutic manipulation of these cells in vivo.
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Affiliation(s)
- Milica Vukmanovic-Stejic
- Department of Immunology and Molecular Pathology, Division of Infection and Immunity, Windeyer Institute of Medical Sciences, University College London, London, United Kingdom
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80
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Abstract
The competency of the adaptive immune function decreases with age, primarily because of the decline in production of naive lymphocytes in the bone marrow and thymus as well as the expansion of incompetent memory lymphocytes. Here I discuss the recent progress on age-associated changes in lymphocytes and their effect on the adaptive immune system.
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Affiliation(s)
- Nan-Ping Weng
- Laboratory of Immunology, National Institute on Aging, National Institutes of Health, 5600 Nathan Shock Drive, Baltimore, Maryland 21224, USA.
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81
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Fletcher JM, Vukmanovic-Stejic M, Dunne PJ, Birch KE, Cook JE, Jackson SE, Salmon M, Rustin MH, Akbar AN. Cytomegalovirus-specific CD4+ T cells in healthy carriers are continuously driven to replicative exhaustion. THE JOURNAL OF IMMUNOLOGY 2006; 175:8218-25. [PMID: 16339561 DOI: 10.4049/jimmunol.175.12.8218] [Citation(s) in RCA: 230] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Repeated antigenic encounter drives proliferation and differentiation of memory T cell pools. An important question is whether certain specific T cells may be driven eventually to exhaustion in elderly individuals since the human life expectancy is increasing. We found that CMV-specific CD4+ T cells were significantly expanded in healthy young and old carriers compared with purified protein derivative-, varicella zoster virus-, EBV-, and HSV-specific populations. These CMV-specific CD4+ T cells exhibited a late differentiated phenotype since they were largely CD27 and CD28 negative and had shorter telomeres. Interestingly, in elderly CMV-seropositive subjects, CD4+ T cells of different specificities were significantly more differentiated than the same cells in CMV-seronegative individuals. This suggested the involvement of bystander-secreted, differentiation-inducing factors during CMV infection. One candidate was IFN-alpha, which induced loss of costimulatory receptors and inhibited telomerase in activated CD4+ T cells and was secreted at high levels by CMV-stimulated plasmacytoid dendritic cells (PDC). The CMV-specific CD4+ T cells in elderly subjects had severely restricted replicative capacity. This is the first description of a human memory T cell population that is susceptible to being lost through end-stage differentiation due to the combined effects of lifelong virus reactivation in the presence of bystander differentiation-inducing factors.
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Affiliation(s)
- Jean M Fletcher
- Department of Immunology and Molecular Pathology, Division of Infection and Immunity, University College London, London, United Kingdom
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82
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Zhou J, Shen X, Huang J, Hodes RJ, Rosenberg SA, Robbins PF. Telomere length of transferred lymphocytes correlates with in vivo persistence and tumor regression in melanoma patients receiving cell transfer therapy. THE JOURNAL OF IMMUNOLOGY 2006; 175:7046-52. [PMID: 16272366 PMCID: PMC1351312 DOI: 10.4049/jimmunol.175.10.7046] [Citation(s) in RCA: 252] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Recent studies have indicated that adoptive immunotherapy with autologous antitumor tumor-infiltrating lymphocytes (TILs) following nonmyeloablative chemotherapy mediates tumor regression in approximately 50% of treated patients with metastatic melanoma, and that tumor regression is correlated with the degree of persistence of adoptively transferred T cells in peripheral blood. These findings, which suggested that the proliferative potential of transferred T cells may play a role in clinical responses, led to the current studies in which telomere length as well as phenotypic markers expressed on the administered TILs were examined. TILs that were associated with objective clinical responses following adoptive transfer possessed a mean telomere length of 6.3 kb, whereas TILs that were not associated with significant clinical responses were significantly shorter, averaging 4.9 kb (p < 0.01). Furthermore, individual TIL-derived T cell clonotypes that persisted in vivo following adoptive cell transfer possessed telomeres that were longer than telomeres of T cell clonotypes that failed to persist (6.2 vs 4.5 kb, respectively; p < 0.001). Expression of the costimulatory molecule CD28 also appeared to be associated with long telomeres and T cell persistence. These results, indicating that the telomere length of transferred lymphocytes correlated with in vivo T cell persistence following adoptive transfer, and coupled with the previous observation that T cell persistence was associated with clinical responses in this adoptive immunotherapy trial, suggest that telomere length and the proliferative potential of the transferred T cells may play a significant role in mediating response to adoptive immunotherapy.
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Affiliation(s)
- Juhua Zhou
- Surgery Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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83
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Male D, Brostoff J, Roth DB, Roitt I. Regulation of the Immune Response. Immunology 2006. [DOI: 10.1016/b0-323-03399-7/50013-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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84
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Huang J, Khong HT, Dudley ME, El-Gamil M, Li YF, Rosenberg SA, Robbins PF. Survival, persistence, and progressive differentiation of adoptively transferred tumor-reactive T cells associated with tumor regression. J Immunother 2005; 28:258-67. [PMID: 15838383 PMCID: PMC2174599 DOI: 10.1097/01.cji.0000158855.92792.7a] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Objective clinical responses have been observed in approximately 50% of patients who received non-myeloablative chemotherapy prior to the adoptive transfer of autologous melanoma-reactive tumor-infiltrating lymphocytes (TILs). Recent studies carried out through the use of antibodies directed against T-cell-receptor beta chain variable region (TRBV) products, as well as by direct sequencing of the expressed TRBV gene products, indicated that clinical responses in this trial were associated with the level of persistence of adoptively transferred T cells. In an attempt to further characterize T cells that persist in vivo following adoptive transfer, five dominant T-cell clonotypes were identified in TIL 2035, an adoptively transferred TIL that was associated with the complete regression of multiple metastases. The most highly persistent clonotype, which expressed the BV1 TR gene product, recognized the MAGE-6 cancer/testis antigen in the context of HLA-A23. This clonotype was detected in peripheral blood for over 16 months following adoptive transfer, expressed relatively higher levels of the co-stimulatory markers CD28 and CD27, and possessed telomeres that were long relative to other clonotypes present in TIL 2035 that showed only short-term persistence. The long-term persistent BV1 clonotype appeared to differentiate more slowly toward an end-stage effector in vivo than short-term persistent clonotypes, as manifested by the downregulation of CD28, CD27, and CD45RO and upregulation of CD57 and CD45RA expression on these T cells. These results indicated that the differentiation stage and replicative history of individual TIL clonotypes might be associated with their ability to survive and to persist in vivo, and progressive differentiation of the persistent clonotypes occurred following adoptive transfer.
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MESH Headings
- Adult
- Antigens, CD/analysis
- Antigens, CD/genetics
- Antigens, Neoplasm
- Cell Differentiation
- Humans
- Immunotherapy, Adoptive
- Lymphocytes, Tumor-Infiltrating/immunology
- Lymphocytes, Tumor-Infiltrating/transplantation
- Male
- Melanoma/immunology
- Melanoma/therapy
- Neoplasm Proteins/immunology
- Phenotype
- Receptors, Antigen, T-Cell, alpha-beta/chemistry
- Receptors, Antigen, T-Cell, alpha-beta/genetics
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Affiliation(s)
- Jianping Huang
- Surgery Branch, National Cancer Institute, National Institute of Health, Bethesda, Maryland 20892, USA
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85
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Pawelec G, Akbar A, Caruso C, Solana R, Grubeck-Loebenstein B, Wikby A. Human immunosenescence: is it infectious? Immunol Rev 2005; 205:257-68. [PMID: 15882359 DOI: 10.1111/j.0105-2896.2005.00271.x] [Citation(s) in RCA: 263] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Morbidity and mortality due to infectious disease is greater in the elderly than in the young, at least partly because of age-associated decreased immune competence, which renders individuals more susceptible to pathogens. This susceptibility is particularly evident for novel infectious agents such as in severe acute respiratory syndrome but is also all too apparent for common pathogens such as influenza. Many years ago, it was noted that the elderly possessed oligoclonal expansions of T cells, especially of CD8(+) cells. At the same time, it was established that cytomegalovirus (CMV) seropositivity was associated with many of the same phenotypic and functional alterations to T-cell immunity that were being reported as biomarkers associated with aging. It was discovered that CMV was the prime driving force behind most of the oligoclonal expansions and altered phenotypes and functions of CD8 cells. Independently, longitudinal studies of a free-living population of the very old in Sweden over the past decade have led to the emerging concept of an 'immune risk phenotype' (IRP), predicting mortality, which was itself found to be associated with CMV seropositivity. These findings support our hypothesis that the manner in which CMV and the host immune system interact is critical in determining the IRP and hence is predictive of mortality. In this sense, then, we suggest that immunosenescence is contagious.
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Affiliation(s)
- Graham Pawelec
- University of Tübingen Medical School, Center for Medical Research, ZMF, Germany.
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86
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Munitic I, Ryan PE, Ashwell JD. T cells in G1 provide a memory-like response to secondary stimulation. THE JOURNAL OF IMMUNOLOGY 2005; 174:4010-8. [PMID: 15778358 DOI: 10.4049/jimmunol.174.7.4010] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The commitment of naive T cells to proliferate is a function of the strength and duration of stimuli mediated by the TCR and coreceptors. Ranges of 2-20 h of stimulation have been reported as necessary in vitro. Whether T cells actually experience uninterrupted stimulation for such long periods under physiological conditions is controversial. Here we ask whether commitment to proliferate requires continuous stimulation, or can T cells integrate intermittent periods of stimulation. T cells were stimulated for two short-term (subthreshold) periods (5-7 h) either sequentially or separated by an interval of rest. Naive lymph node T cells were able to integrate interrupted stimulation, even when the duration of rest was as long as 2 days. Furthermore, when short-term-stimulated T cells were separated by density, three populations were observed: low density blasts, intermediate density G(1) cells, and high density G(0) cells. Low density cells progressed to division without further stimulation, whereas G(0) and G(1) cells remained undivided. However, after a period of rest, a second subthreshold stimulation caused the G(1) but not the G(0) fraction to quickly proceed through the cell cycle. We conclude that noncycling T cells in the G(1) phase of the cell cycle remain in a state of readiness for prolonged periods of time, and may represent a population of memory-like effectors capable of responding rapidly to antigenic challenge.
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Affiliation(s)
- Ivana Munitic
- Laboratory of Immune Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA
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87
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Plunkett FJ, Franzese O, Belaramani LL, Fletcher JM, Gilmour KC, Sharifi R, Khan N, Hislop AD, Cara A, Salmon M, Gaspar HB, Rustin MHA, Webster D, Akbar AN. The impact of telomere erosion on memory CD8+ T cells in patients with X-linked lymphoproliferative syndrome. Mech Ageing Dev 2005; 126:855-65. [PMID: 15992610 DOI: 10.1016/j.mad.2005.03.006] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2005] [Revised: 03/14/2005] [Accepted: 03/18/2005] [Indexed: 10/25/2022]
Abstract
Patients with X-linked lymphoproliferative syndrome (XLP) experience excessive T cell proliferation after primary Epstein-Barr virus (EBV) infection, due to mutations in the signalling lymphocyte activation molecule (SLAM) associated protein (SAP) molecule. We examined the impact of dysfunctional proliferative control on the extent of CD8+ T cell differentiation in XLP patients who recovered from primary EBV infection. Although these young patients have normal numbers of lytic and latent EBV-epitope-specific CD8+ T cells, they were extremely differentiated as defined by loss of CCR7 and CD27, low telomerase activity and very short telomeres. This was not a direct effect arising from the loss of SAP, but was due to excessive T cell stimulation due to this defect. Thus, transduction of XLP CD8+ T cells with the catalytic component of telomerase (hTERT), but not SAP, prevented telomere loss and considerably extended proliferative lifespan in vitro. These results indicate that excessive proliferation in CD8+ T cells in XLP patients may lead to end-stage differentiation and loss of functional EBV-specific CD8+ T cells through replicative senescence. This may contribute to the defective immunity found in XLP patients who survive acute EBV infection who develop EBV-related B cell lymphomas before the fourth decade of life.
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Affiliation(s)
- Fiona J Plunkett
- Department of Immunology and Molecular Pathology, Royal Free and University College Medical School, London, UK
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88
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Röth A, Baerlocher GM, Schertzer M, Chavez E, Dührsen U, Lansdorp PM. Telomere loss, senescence, and genetic instability in CD4+ T lymphocytes overexpressing hTERT. Blood 2005; 106:43-50. [PMID: 15741219 PMCID: PMC1895130 DOI: 10.1182/blood-2004-10-4144] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Little is known about the long-term consequences of overexpression of the human telomerase reverse transcriptase (hTERT) gene in T lymphocytes. To address this issue, we transduced polyclonal as well as clonally derived populations of naive and memory CD44 T cells from 2 healthy donors (aged 24 and 34 years) with retroviral vectors encoding green fluorescence protein (GFP) and hTERT (GFP-hTERT) or GFP alone. After transduction, cells were sorted on the basis of GFP expression and cultured in vitro until senescence. T cells transduced with hTERT exhibited high stable telomerase activity throughout the culture period. Relative to GFP controls, minor changes in overall gene expression were observed yet the proliferative lifespan of the hTERT-transduced populations was significantly increased and the rate of telomere loss was lower. Nevertheless, hTERT-transduced cells showed progressive telomere loss and had shorter telomeres at senescence than controls (2.3 +/- 0.3 kilobase [kb] versus 3.4 +/- 0.1 kb). Furthermore, a population of cells with 4N DNA consisting of binucleated cells with connected nuclei emerged in the hTERT-transduced cells prior to senescence. We conclude that overexpression of hTERT in CD4+ T cells provides a proliferative advantage independent of the average telomere length but does not prevent eventual genetic instability and replicative senescence.
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Affiliation(s)
- Alexander Röth
- Terry Fox Laboratory, British Columbia Cancer Agency, 12th floor, 675 W 10th Ave, Vancouver, BC, V5Z 1L3, Canada
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89
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Zanetti M, Hernandez X, Langlade-Demoyen P. Telomerase reverse transcriptase as target for anti-tumor T cell responses in humans. ACTA ACUST UNITED AC 2005; 27:87-104. [PMID: 15711953 DOI: 10.1007/s00281-004-0197-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2004] [Accepted: 12/15/2004] [Indexed: 10/25/2022]
Abstract
Human telomerase reverse transcriptase, a ribonucleoprotein intimately connected with the process of cell immortalization, is overexpressed in the vast majority of cancer cells, irrespective of their histological origin. Telomerase is currently viewed as the first antigen with the characteristics of common tumor antigen in humans, and it constitutes a potentially valuable target for attempts to control tumors through CD8 T cell immunity. Telomerase is a self antigen, making it possible that self tolerance imposes severe restrictions on our ability to generate effective anti-tumor immune responses in humans. In this article we review current studies on the antigenic and immunogenic properties of the human telomerase reverse transcriptase, placing them in the context of self tolerance and the size of the available CD8 T cell repertoire restricted by the HLA A2 molecule.
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Affiliation(s)
- Maurizio Zanetti
- The Laboratory of Immunology, Department of Medicine and Cancer Center, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0837, USA.
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90
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Abstract
T-cell immunological memory consists largely of clones of proliferating lymphocytes maintained by antigenic stimulation and the survival and proliferative effects of cytokines. The duration of survival of memory clones in humans is determine by the Hayflick limit on the number of cell divisions, the rate of cycling of memory cells and factors that control erosion of telomeres, including mechanisms that control telomerase.
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Affiliation(s)
- Peter C L Beverley
- The Edward Jenner Institute for Vaccine Research, Compton, Berkshire RG207NN, UK.
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91
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Akbar AN, Beverley PCL, Salmon M. Will telomere erosion lead to a loss of T-cell memory? Nat Rev Immunol 2004; 4:737-43. [PMID: 15343372 DOI: 10.1038/nri1440] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Evidence is accumulating that elderly individuals are more susceptible to infection with organisms to which they were previously immune. This indicates that there might be a limit to the persistence of immune memory. This fact is particularly disturbing because the average life expectancy of humans has almost doubled in the past 200 years and is still increasing. We discuss mechanisms that might constrain the persistence of memory T cells and consider whether humans will suffer from memory T-cell exhaustion as life expectancy increases.
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Affiliation(s)
- Arne N Akbar
- Department of Immunology and Molecular Pathology, The Windeyer Building, 46 Cleveland Street, Division of Infection and Immunity, Royal Free and University College Medical School, London W1T 4JF, UK.
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