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Dinges SS, Amini K, Notarangelo LD, Delmonte OM. Primary and secondary defects of the thymus. Immunol Rev 2024; 322:178-211. [PMID: 38228406 PMCID: PMC10950553 DOI: 10.1111/imr.13306] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
The thymus is the primary site of T-cell development, enabling generation, and selection of a diverse repertoire of T cells that recognize non-self, whilst remaining tolerant to self- antigens. Severe congenital disorders of thymic development (athymia) can be fatal if left untreated due to infections, and thymic tissue implantation is the only cure. While newborn screening for severe combined immune deficiency has allowed improved detection at birth of congenital athymia, thymic disorders acquired later in life are still underrecognized and assessing the quality of thymic function in such conditions remains a challenge. The thymus is sensitive to injury elicited from a variety of endogenous and exogenous factors, and its self-renewal capacity decreases with age. Secondary and age-related forms of thymic dysfunction may lead to an increased risk of infections, malignancy, and autoimmunity. Promising results have been obtained in preclinical models and clinical trials upon administration of soluble factors promoting thymic regeneration, but to date no therapy is approved for clinical use. In this review we provide a background on thymus development, function, and age-related involution. We discuss disease mechanisms, diagnostic, and therapeutic approaches for primary and secondary thymic defects.
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Affiliation(s)
- Sarah S. Dinges
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine, Charité – Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Kayla Amini
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Luigi D. Notarangelo
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | - Ottavia M. Delmonte
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA
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2
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Lagou MK, Karagiannis GS. Obesity-induced thymic involution and cancer risk. Semin Cancer Biol 2023; 93:3-19. [PMID: 37088128 DOI: 10.1016/j.semcancer.2023.04.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 04/19/2023] [Accepted: 04/20/2023] [Indexed: 04/25/2023]
Abstract
Declining thymic functions associated either with old age (i.e., age-related thymic involution), or with acute involution as a result of stress, infectious disease, or cytoreductive therapies (e.g., chemotherapy/radiotherapy), have been associated with cancer development. A key mechanism underlying such increased cancer risk is the thymus-dependent debilitation of adaptive immunity, which is responsible for orchestrating immunoediting mechanisms and tumor immune surveillance. In the past few years, a blooming set of evidence has intriguingly linked obesity with cancer development and progression. The majority of such studies has focused on obesity-driven chronic inflammation, steroid/sex hormone and adipokine production, and hyperinsulinemia, as principal factors affecting the tumor microenvironment and driving the development of primary malignancy. However, experimental observations about the negative impact of obesity on T cell development and maturation have existed for more than half a century. Here, we critically discuss the molecular and cellular mechanisms of obesity-driven thymic involution as a previously underrepresented intermediary pathology leading to cancer development and progression. This knowledge could be especially relevant in the context of childhood obesity, because impaired thymic function in young individuals leads to immune system abnormalities, and predisposes to various pediatric cancers. A thorough understanding behind the molecular and cellular circuitries governing obesity-induced thymic involution could therefore help towards the rationalized development of targeted thymic regeneration strategies for obese individuals at high risk of cancer development.
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Affiliation(s)
- Maria K Lagou
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA; Tumor Microenvironment of Metastasis Program, Albert Einstein Cancer Center, Bronx, NY, USA
| | - George S Karagiannis
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA; Tumor Microenvironment of Metastasis Program, Albert Einstein Cancer Center, Bronx, NY, USA; Cancer Dormancy and Tumor Microenvironment Institute, Albert Einstein College of Medicine, Bronx, NY, USA; Gruss-Lipper Biophotonics Center, Albert Einstein College of Medicine, Bronx, NY, USA; Integrated Imaging Program for Cancer Research, Albert Einstein College of Medicine, Bronx, NY, USA.
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3
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Cardinale A, De Luca CD, Locatelli F, Velardi E. Thymic Function and T-Cell Receptor Repertoire Diversity: Implications for Patient Response to Checkpoint Blockade Immunotherapy. Front Immunol 2021; 12:752042. [PMID: 34899700 PMCID: PMC8652142 DOI: 10.3389/fimmu.2021.752042] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/05/2021] [Indexed: 01/05/2023] Open
Abstract
The capacity of T cells to recognize and mount an immune response against tumor antigens depends on the large diversity of the T-cell receptor (TCR) repertoire generated in the thymus during the process of T-cell development. However, this process is dramatically impaired by immunological insults, such as that caused by cytoreductive cancer therapies and infections, and by the physiological decline of thymic function with age. Defective thymic function and a skewed TCR repertoire can have significant clinical consequences. The presence of an adequate pool of T cells capable of recognizing specific tumor antigens is a prerequisite for the success of cancer immunotherapy using checkpoint blockade therapy. However, while this approach has improved the chances of survival of patients with different types of cancer, a large proportion of them do not respond. The limited response rate to checkpoint blockade therapy may be linked to a suboptimal TCR repertoire in cancer patients prior to therapy. Here, we focus on the role of the thymus in shaping the T-cell pool in health and disease, discuss how the TCR repertoire influences patients’ response to checkpoint blockade therapy and highlight approaches able to manipulate thymic function to enhance anti-tumor immunity.
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Affiliation(s)
- Antonella Cardinale
- Department of Pediatric Hematology and Oncology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy
| | | | - Franco Locatelli
- Department of Pediatric Hematology and Oncology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy.,Department of Maternal and Child Health, Sapienza University of Rome, Rome, Italy
| | - Enrico Velardi
- Department of Pediatric Hematology and Oncology, Bambino Gesù Children's Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS), Rome, Italy
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4
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Ducloux D, Legendre M, Bamoulid J, Saas P, Courivaud C, Crepin T. End-Stage Renal Disease-Related Accelerated Immune Senescence: Is Rejuvenation of the Immune System a Therapeutic Goal? Front Med (Lausanne) 2021; 8:720402. [PMID: 34540869 PMCID: PMC8446427 DOI: 10.3389/fmed.2021.720402] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 08/17/2021] [Indexed: 02/05/2023] Open
Abstract
End-stage renal disease (ESRD) patients exhibit clinical features of premature ageing, including frailty, cardiovascular disease, and muscle wasting. Accelerated ageing also concerns the immune system. Patients with ESRD have both immune senescence and chronic inflammation that are resumed in the so-called inflammaging syndrome. Immune senescence is particularly characterised by premature loss of thymic function that is associated with hyporesponsiveness to vaccines, susceptibility to infections, and death. ESRD-related chronic inflammation has multiple causes and participates to accelerated cardiovascular disease. Although, both characterisation of immune senescence and its consequences are relatively well-known, mechanisms are more uncertain. However, prevention of immune senescence/inflammation or/and rejuvenation of the immune system are major goal to ameliorate clinical outcomes of ESRD patients.
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Affiliation(s)
- Didier Ducloux
- Inserm, UMR1098, Federation Hospitalo-Universitaire INCREASE, Besançon, France.,University Bourgogne Franche-Comté, Faculté de Médecine et de Pharmacie, LabEx LipSTIC, Besançon, France.,Structure Fédérative de Recherche, SFR FED4234, Besançon, France.,CHU Besançon, Department of Nephrology, Dialysis, and Renal Transplantation, Besançon, France
| | - Mathieu Legendre
- Inserm, UMR1098, Federation Hospitalo-Universitaire INCREASE, Besançon, France.,University Bourgogne Franche-Comté, Faculté de Médecine et de Pharmacie, LabEx LipSTIC, Besançon, France
| | - Jamal Bamoulid
- Inserm, UMR1098, Federation Hospitalo-Universitaire INCREASE, Besançon, France.,University Bourgogne Franche-Comté, Faculté de Médecine et de Pharmacie, LabEx LipSTIC, Besançon, France.,Structure Fédérative de Recherche, SFR FED4234, Besançon, France.,CHU Besançon, Department of Nephrology, Dialysis, and Renal Transplantation, Besançon, France
| | - Philippe Saas
- Inserm, UMR1098, Federation Hospitalo-Universitaire INCREASE, Besançon, France.,University Bourgogne Franche-Comté, Faculté de Médecine et de Pharmacie, LabEx LipSTIC, Besançon, France.,Structure Fédérative de Recherche, SFR FED4234, Besançon, France.,EFS Bourgogne Franche-Comté, Plateforme de Biomonitoring, CIC 1431/UMR1098, Besançon, France
| | - Cécile Courivaud
- Inserm, UMR1098, Federation Hospitalo-Universitaire INCREASE, Besançon, France.,University Bourgogne Franche-Comté, Faculté de Médecine et de Pharmacie, LabEx LipSTIC, Besançon, France.,Structure Fédérative de Recherche, SFR FED4234, Besançon, France.,CHU Besançon, Department of Nephrology, Dialysis, and Renal Transplantation, Besançon, France
| | - Thomas Crepin
- Inserm, UMR1098, Federation Hospitalo-Universitaire INCREASE, Besançon, France.,CHU Besançon, Department of Nephrology, Dialysis, and Renal Transplantation, Besançon, France
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5
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Abstract
Following periods of haematopoietic cell stress, such as after chemotherapy, radiotherapy, infection and transplantation, patient outcomes are linked to the degree of immune reconstitution, specifically of T cells. Delayed or defective recovery of the T cell pool has significant clinical consequences, including prolonged immunosuppression, poor vaccine responses and increased risks of infections and malignancies. Thus, strategies that restore thymic function and enhance T cell reconstitution can provide considerable benefit to individuals whose immune system has been decimated in various settings. In this Review, we focus on the causes and consequences of impaired adaptive immunity and discuss therapeutic strategies that can recover immune function, with a particular emphasis on approaches that can promote a diverse repertoire of T cells through de novo T cell formation.
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6
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Vahkal B, Yegorov S, Onyilagha C, Donner J, Reddick D, Shrivastav A, Uzonna J, Good SV. Immune System Effects of Insulin-Like Peptide 5 in a Mouse Model. Front Endocrinol (Lausanne) 2020; 11:610672. [PMID: 33519716 PMCID: PMC7841425 DOI: 10.3389/fendo.2020.610672] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Accepted: 11/16/2020] [Indexed: 12/25/2022] Open
Abstract
INTRODUCTION Insulin-like peptide 5 (INSL5) is a peptide hormone with proposed actions in glucose homeostasis and appetite regulation via its cognate receptor, relaxin family peptide receptor 4 (RXFP4). Here, we look for evidence for their involvement in the immune system using a mouse model. METHODS In silico analyses: we queried public databases for evidence of expression of INSL5-RXFP4 in immune system tissues/cells (NCBI's SRA and GeoProfiles) and disorders (EMBO-EBI) and performed phylogenetic footprinting to look for evidence that they are regulated by immune-associated transcription factors (TFs). Experimental analyses: We characterized the expression and correlation of INSL5/RXFP4 and other immune system markers in central and peripheral immune organs from C57/bl6 mice in seven cohorts. We tested whether fluctuations in circulating INSL5 induce an immune response, by injecting mice with 30 μg/kg of INSL5 peptide in the peritoneum, and examining levels of immune markers and metabolic peptides in plasma. Lastly, we quantified the expression of Rxfp4 in T-cells, dendritic cells and cell lines derived from human and mouse and tested the hypothesis that co-incubation of ANA-1 cells in INSL5 and LPS alters cytokine expression. RESULTS We find Insl5 expression only in thymus (in addition to colon) where its expression was highly correlated with Il-7, a marker of thymocyte development. This result is consistent with our in silico findings that Insl5 is highly expressed in thymic DP, DN thymocytes and cortical TEC's, and with evidence that it is regulated by thymocyte-associated TF's. We find Rxfp4 expression in all immune organs, and moderately high levels in DCs, particularly splenic DCs, and evidence that it is regulated by immune-associated TF's, such as STAT's and GATA. Systemic effects: We observed significantly elevated concentrations of blood GLP-1, GIP, GCG and PYY following intraperitoneal injection of INSL5, and significantly altered expression of cytokines IL-5, IL-7, M-CSF, IL-15, IL-27 and MIP-2. Immune cell effects: Incubation of ANA-1 cells with INSL5 impeded cell growth and led to a transient elevation of IL-15 and sustained reduction in IL-1β, IL-6 and TNFα. CONCLUSION We propose that INSL5-RXFP4 play a novel role in both central and peripheral immune cell signaling.
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Affiliation(s)
- Brett Vahkal
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada
- *Correspondence: Brett Vahkal, ; Sara V. Good,
| | - Sergey Yegorov
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada
| | | | | | - Dean Reddick
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada
| | | | - Jude Uzonna
- Department of Immunology, University of Manitoba, Winnipeg, MB, Canada
| | - Sara V. Good
- Department of Biology, University of Winnipeg, Winnipeg, MB, Canada
- *Correspondence: Brett Vahkal, ; Sara V. Good,
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7
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El-Kadiry AEH, Rafei M. Restoring thymic function: Then and now. Cytokine 2019; 120:202-209. [PMID: 31108430 DOI: 10.1016/j.cyto.2019.05.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 05/07/2019] [Accepted: 05/10/2019] [Indexed: 01/21/2023]
Abstract
Thymic vulnerability, a leading cause of defective immunity, was discovered decades ago. To date, several strategies have been investigated to unveil any immunorestorative capacities they might confer. Studies exploiting castration, transplantation, adoptive cell therapies, hormones/growth factors, and cytokines have demonstrated enhanced in vitro and in vivo thymopoiesis, albeit with clinical restrictions. In this review, we will dissect the thymus on a physiological and pathological level and discuss the pros and cons of several strategies esteemed thymotrophic from a pre-clinical perspective. Finally, we will shed light on interleukin (IL)-21, a pharmacologically-promising cytokine with a significant thymotrophic nature, and elaborate on its potential clinical efficacy and safety in immune-deficient subjects.
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Affiliation(s)
- Abed El-Hakim El-Kadiry
- Department of Biomedical Sciences, Faculty of Medicine, Université de Montréal, Montréal, Qc, Canada; Montreal Heart Institute, Montréal, Qc, Canada
| | - Moutih Rafei
- Department of Pharmacology and Physiology, Université de Montréal, Montréal, Qc, Canada; Department of Microbiology, Infectious Diseases and Immunology, Université de Montréal, Montréal, Qc, Canada; Department of Microbiology and Immunology, McGill University, Montréal, Qc, Canada.
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8
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Bodart G, Farhat K, Renard-Charlet C, Becker G, Plenevaux A, Salvatori R, Geenen V, Martens H. The Severe Deficiency of the Somatotrope GH-Releasing Hormone/Growth Hormone/Insulin-Like Growth Factor 1 Axis of Ghrh-/- Mice Is Associated With an Important Splenic Atrophy and Relative B Lymphopenia. Front Endocrinol (Lausanne) 2018; 9:296. [PMID: 29928261 PMCID: PMC5997896 DOI: 10.3389/fendo.2018.00296] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/17/2018] [Indexed: 11/13/2022] Open
Abstract
A debate is still open about the precise control exerted by the somatotrope GH-releasing hormone (GHRH)/growth hormone (GH)/insulin-like growth factor 1 axis on the immune system. The objective of this study was to directly address this question through the use of Ghrh-/- mice that exhibit a severe deficiency of their somatotrope axis. After control backcross studies and normalization for the reduced global weight of transgenic mice, no difference in weight and cellularity of the thymus was observed in Ghrh-/- mice when compared with C57BL/6 wild-type (WT) control mice. Similarly, no significant change was observed in frequency and number of thymic T cell subsets. In the periphery, Ghrh-/- mice exhibited an increase in T cell proportion associated with a higher frequency of sjTREC and naïve T cells. However, all Ghrh-/- mice displayed an absolute and relative splenic atrophy, in parallel with a decrease in B cell percentage. GH supplementation of transgenic mice for 6 weeks induced a significant increase in their global as well as absolute and relative splenic weight. Interestingly, the classical thymus involution following dexamethasone administration was shown to recover in WT mice more quickly than in mutant mice. Altogether, these data show that the severe somatotrope deficiency of Ghrh-/- mice essentially impacts the spleen and B compartment of the adaptive immune system, while it only marginally affects thymic function and T cell development.
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Affiliation(s)
- Gwennaelle Bodart
- GIGA-I Center of Immunoendocrinology, GIGA Research Institute, University of Liege, Liège, Belgium
| | - Khalil Farhat
- GIGA-I Center of Immunoendocrinology, GIGA Research Institute, University of Liege, Liège, Belgium
| | - Chantal Renard-Charlet
- GIGA-I Center of Immunoendocrinology, GIGA Research Institute, University of Liege, Liège, Belgium
| | | | - Alain Plenevaux
- Cyclotron Research Center, University of Liege, Liège, Belgium
| | - Roberto Salvatori
- Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, The Johns Hopkins University, Baltimore, MD, United States
| | - Vincent Geenen
- GIGA-I Center of Immunoendocrinology, GIGA Research Institute, University of Liege, Liège, Belgium
- *Correspondence: Vincent Geenen,
| | - Henri Martens
- GIGA-I Center of Immunoendocrinology, GIGA Research Institute, University of Liege, Liège, Belgium
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9
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Exploring the link between innate immune activation and thymic function by measuring sCD14 and TRECs in HIV patients living in Belgium. PLoS One 2017; 12:e0185761. [PMID: 29049344 PMCID: PMC5648129 DOI: 10.1371/journal.pone.0185761] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2017] [Accepted: 09/19/2017] [Indexed: 12/31/2022] Open
Abstract
Microbial translocation is now viewed as a central event in the pathogenesis of chronic inflammation during HIV infection. Thymic function failure is another crucial factor involved in HIV disease progression. The goal of this study was to explore the hypothesis of potential links between microbial translocation and thymic function in HIV-1 patients living in Belgium. The extent of microbial translocation was assessed through the measurement of soluble CD14 (sCD14). T-cell receptor excision circles (sjTRECs and dβTRECs) were used as a measure of thymic function. Data were collected from 75 HIV-infected patients. Simple and complex linear regressions were done to analyze the link between these two processes. We found a statistically relevant negative correlation between thymopoiesis (sjTREC) and sCD14 level (p = 0.004). These results suggest a link between thymic function failure, microbial translocation and innate immune activation.
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10
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Chaudhry MS, Velardi E, Malard F, van den Brink MRM. Immune Reconstitution after Allogeneic Hematopoietic Stem Cell Transplantation: Time To T Up the Thymus. THE JOURNAL OF IMMUNOLOGY 2017; 198:40-46. [PMID: 27994167 DOI: 10.4049/jimmunol.1601100] [Citation(s) in RCA: 63] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/23/2016] [Accepted: 09/01/2016] [Indexed: 01/09/2023]
Abstract
The success of allogeneic hematopoietic stem cell transplantation, a key treatment for many disorders, is intertwined with T cell immune reconstitution. The thymus plays a key role post allogeneic hematopoietic stem cell transplantation in the generation of a broad but self-tolerant T cell repertoire, but it is exquisitely sensitive to a range of insults during the transplant period, including conditioning regimens, corticosteroids, infections, and graft-versus-host disease. Although endogenous thymic repair is possible it is often suboptimal, and there is a need to develop exogenous strategies to help regenerate the thymus. Therapies currently in clinical trials in the transplant setting include keratinocyte growth factor, cytokines (IL-7 and IL-22), and hormonal modulation including sex steroid inhibition and growth hormone administration. Such regenerative strategies may ultimately enable the thymus to play as prominent a role after transplant as it once did in early childhood, allowing a more complete restoration of the T cell compartment.
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Affiliation(s)
- Mohammed S Chaudhry
- Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065
| | - Enrico Velardi
- Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065
| | - Florent Malard
- Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065
| | - Marcel R M van den Brink
- Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065; .,Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY 10065; and.,Department of Immunology and Microbial Pathogenesis, Weill Cornell Medical College, New York, NY 10021
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11
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Esposito A, Capalbo D, De Martino L, Rezzuto M, Di Mase R, Pignata C, Salerno M. Long-term effects of growth hormone (GH) replacement therapy on hematopoiesis in a large cohort of children with GH deficiency. Endocrine 2016; 53:192-8. [PMID: 26511947 DOI: 10.1007/s12020-015-0781-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 10/19/2015] [Indexed: 10/22/2022]
Abstract
The aim of our prospective case-control study was to evaluate long-term effects of GH replacement therapy on erythrocytes parameters, leukocytes, and platelets numbers in a large cohort of children with isolated GH deficiency (GHD). Hemoglobin (Hb) concentration, hematocrit (Hct), mean corpuscular volume, mean corpuscular hemoglobin, red cell distribution width, number of erythrocytes, leukocytes, neutrophils, lymphocytes, monocytes and platelets, ferritin, and C-reactive protein were evaluated in 85 children with isolated GHD (10.20 ± 3.50 years) before and annually during the first 5 years of GH replacement therapy and in 85 healthy children age and sex comparable to patients during 5 years of follow-up. Compared with controls, GHD children at study entry showed lower Hb (-1.18 ± 0.87 vs. -0.40 ± 0.90 SDS, p < 0.0001), red cells number (-0.24 ± 0.81 vs. 0.25 ± 1.14 SDS, p < 0.0001), and Hct (-1.18 ± 0.86 vs. -0.68 ± 0.99 SDS, p < 0.0001). Twelve GHD patients (14 %) showed a normocytic anemia. GH therapy was associated with a significant increase in Hb, Hct, and red cells number which became all comparable to controls within the first 2 years of treatment. Moreover, hemoglobin levels normalized in all anemic GHD patients after 5 years of therapy. No difference between patients and controls was found in leukocytes and platelets numbers neither at baseline nor during the study. GHD in childhood is associated with an impairment of erythropoiesis which causes a normocytic anemia in a considerable percentage of patients. GH replacement therapy exerts a beneficial effect leading to a significant increase of erythrocytes parameters and recovery from anemia. Neither GHD nor GH replacement treatment exerts effects on leukocytes or platelets numbers.
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Affiliation(s)
- Andrea Esposito
- Pediatric Endocrinology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy
| | - Donatella Capalbo
- Pediatric Endocrinology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy
| | - Lucia De Martino
- Pediatric Endocrinology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy
| | - Martina Rezzuto
- Pediatric Endocrinology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy
| | - Raffaella Di Mase
- Pediatric Endocrinology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy
| | - Claudio Pignata
- Pediatric Immunology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy
| | - Mariacarolina Salerno
- Pediatric Endocrinology Unit, Department of Translational Medical Sciences, University of Naples "Federico II", via Sergio Pansini 5, 80131, Naples, Italy.
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12
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Savino W, Mendes-da-Cruz DA, Lepletier A, Dardenne M. Hormonal control of T-cell development in health and disease. Nat Rev Endocrinol 2016; 12:77-89. [PMID: 26437623 DOI: 10.1038/nrendo.2015.168] [Citation(s) in RCA: 75] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The physiology of the thymus, the primary lymphoid organ in which T cells are generated, is controlled by hormones. Data from animal models indicate that several peptide and nonpeptide hormones act pleiotropically within the thymus to modulate the proliferation, differentiation, migration and death by apoptosis of developing thymocytes. For example, growth hormone and prolactin can enhance thymocyte proliferation and migration, whereas glucocorticoids lead to the apoptosis of these developing cells. The thymus undergoes progressive age-dependent atrophy with a loss of cells being generated and exported, therefore, hormone-based therapies are being developed as an alternative strategy to rejuvenate the organ, as well as to augment thymocyte proliferation and the export of mature T cells to peripheral lymphoid organs. Some hormones (such as growth hormone and progonadoliberin-1) are also being used as therapeutic agents to treat immunodeficiency disorders associated with thymic atrophy, such as HIV infection. In this Review, we discuss the accumulating data that shows the thymus gland is under complex and multifaceted hormonal control that affects the process of T-cell development in health and disease.
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Affiliation(s)
- Wilson Savino
- Laboratory of Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Avenue Brasil 4365, 21045-900, Manguinhos, Rio de Janeiro, Brazil
| | - Daniella Arêas Mendes-da-Cruz
- Laboratory of Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Avenue Brasil 4365, 21045-900, Manguinhos, Rio de Janeiro, Brazil
| | - Ailin Lepletier
- Laboratory of Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Avenue Brasil 4365, 21045-900, Manguinhos, Rio de Janeiro, Brazil
| | - Mireille Dardenne
- Hôpital Necker, CNRS UMR 8147, Université Paris Descartes, 75015 Paris, France
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13
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Jurberg AD, Vasconcelos-Fontes L, Cotta-de-Almeida V. A Tale from TGF-β Superfamily for Thymus Ontogeny and Function. Front Immunol 2015; 6:442. [PMID: 26441956 PMCID: PMC4564722 DOI: 10.3389/fimmu.2015.00442] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2015] [Accepted: 08/14/2015] [Indexed: 12/16/2022] Open
Abstract
Multiple signaling pathways control every aspect of cell behavior, organ formation, and tissue homeostasis throughout the lifespan of any individual. This review takes an ontogenetic view focused on the large superfamily of TGF-β/bone morphogenetic protein ligands to address thymus morphogenesis and function in T cell differentiation. Recent findings on a role of GDF11 for reversing aging-related phenotypes are also discussed.
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Affiliation(s)
- Arnon Dias Jurberg
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (Fiocruz) , Rio de Janeiro , Brazil ; Graduate Program in Cell and Developmental Biology, Institute of Biomedical Sciences, Federal University of Rio de Janeiro , Rio de Janeiro , Brazil
| | - Larissa Vasconcelos-Fontes
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (Fiocruz) , Rio de Janeiro , Brazil
| | - Vinícius Cotta-de-Almeida
- Laboratory on Thymus Research, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (Fiocruz) , Rio de Janeiro , Brazil
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14
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Bodart G, Goffinet L, Morrhaye G, Farhat K, de Saint-Hubert M, Debacq-Chainiaux F, Swine C, Geenen V, Martens HJ. Somatotrope GHRH/GH/IGF-1 axis at the crossroads between immunosenescence and frailty. Ann N Y Acad Sci 2015; 1351:61-7. [PMID: 26284958 DOI: 10.1111/nyas.12857] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Immunosenescence, characterized by complex modifications of immunity with age, could be related to frailty syndrome in elderly individuals, leading to an inadequate response to minimal aggression. Functional decline (i.e., the loss of ability to perform activities of daily living) is related to frailty and decreased physiological reserves and is a frequent outcome of hospitalization in older patients. Links between immunosenescence and frailty have been explored and 20 immunological parameters, including insulin-like growth factor-1 (IGF-1), thymopoeisis, and telomere length, were shown to be affected in elderly patients with functional decline. A strong relationship between IGF-1 and thymic ouput was evidenced. IGF-1, a mediator of growth hormone (GH), was subsequently shown to induce interleukin-7 secretion in cultured primary human thymic epithelial cells. We are exploring the stress hypothesis in which an acute stressor is used as the discriminator of frailty susceptibility. GH can counteract the deleterious immunosuppressive effects of stress-induced steroids. Under nonstress conditions, the immunosenescent system preserves physiological responses, while under stress conditions, the combination of immunosenescence and a defect in the somatotrope axis might lead to functional decline.
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Affiliation(s)
| | | | | | - Khalil Farhat
- GIGA Research Institute, University of Liège, Liège, Belgium
| | - Marie de Saint-Hubert
- Department of Geriatrics, University Hospital of Mont-Godinne, NARILIS-Namur Research Institute for Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Florence Debacq-Chainiaux
- Unit of Research on Cellular Biology, NARILIS-Namur Research Institute for Life Sciences, University of Namur (FUNDP), Namur, Belgium
| | - Christian Swine
- Department of Geriatrics, University Hospital of Mont-Godinne, NARILIS-Namur Research Institute for Life Sciences, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Vincent Geenen
- GIGA Research Institute, University of Liège, Liège, Belgium
| | - Henri J Martens
- GIGA Research Institute, University of Liège, Liège, Belgium
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15
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Trade off situation between thymus and growth hormone: age-related decline of growth hormone is a cause of thymic involution but favorable for elongation of lifespan. Biogerontology 2015; 17:55-9. [DOI: 10.1007/s10522-015-9590-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 06/26/2015] [Indexed: 10/23/2022]
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16
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Yoshida K, Nakashima E, Kubo Y, Yamaoka M, Kajimura J, Kyoizumi S, Hayashi T, Ohishi W, Kusunoki Y. Inverse associations between obesity indicators and thymic T-cell production levels in aging atomic-bomb survivors. PLoS One 2014; 9:e91985. [PMID: 24651652 PMCID: PMC3961282 DOI: 10.1371/journal.pone.0091985] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Accepted: 02/16/2014] [Indexed: 12/15/2022] Open
Abstract
Reduction of the naive T-cell population represents a deteriorating state in the immune system that occurs with advancing age. In animal model studies, obesity compromises the T-cell immune system as a result of enhanced adipogenesis in primary lymphoid organs and systemic inflammation. In this study, to test the hypothesis that obesity may contribute to the aging of human T-cell immunity, a thousand atomic-bomb survivors were examined for obesity status and ability to produce naive T cells, i.e., T-cell receptor excision circle (TREC) numbers in CD4 and CD8 T cells. The number of TRECs showed a strong positive correlation with naive T cell numbers, and lower TREC numbers were associated with higher age. We found that the TREC number was inversely associated with levels of obesity indicators (BMI, hemoglobin A1c) and serum CRP levels. Development of type-2 diabetes and fatty liver was also associated with lower TREC numbers. This population study suggests that obesity with enhanced inflammation is involved in aging of the human T-cell immune system. Given the fact that obesity increases the risk of numerous age-related diseases, attenuated immune competence is a possible mechanistic link between obesity and disease development among the elderly.
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Affiliation(s)
- Kengo Yoshida
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
- * E-mail:
| | - Eiji Nakashima
- Department of Statistics, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Yoshiko Kubo
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Mika Yamaoka
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Junko Kajimura
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Seishi Kyoizumi
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Tomonori Hayashi
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Waka Ohishi
- Department of Clinical Studies, Radiation Effects Research Foundation, Hiroshima, Japan
| | - Yoichiro Kusunoki
- Department of Radiobiology/Molecular Epidemiology, Radiation Effects Research Foundation, Hiroshima, Japan
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17
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Rezzani R, Nardo L, Favero G, Peroni M, Rodella LF. Thymus and aging: morphological, radiological, and functional overview. AGE (DORDRECHT, NETHERLANDS) 2014; 36:313-51. [PMID: 23877171 PMCID: PMC3889907 DOI: 10.1007/s11357-013-9564-5] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 07/01/2013] [Indexed: 05/20/2023]
Abstract
Aging is a continuous process that induces many alterations in the cytoarchitecture of different organs and systems both in humans and animals. Moreover, it is associated with increased susceptibility to infectious, autoimmune, and neoplastic processes. The thymus is a primary lymphoid organ responsible for the production of immunocompetent T cells and, with aging, it atrophies and declines in functions. Universality of thymic involution in all species possessing thymus, including human, indicates it as a long-standing evolutionary event. Although it is accepted that many factors contribute to age-associated thymic involution, little is known about the mechanisms involved in the process. The exact time point of the initiation is not well defined. To address the issue, we report the exact age of thymus throughout the review so that readers can have a nicely pictured synoptic view of the process. Focusing our attention on the different stages of the development of the thymus gland (natal, postnatal, adult, and old), we describe chronologically the morphological changes of the gland. We report that the thymic morphology and cell types are evolutionarily preserved in several vertebrate species. This finding is important in understanding the similar problems caused by senescence and other diseases. Another point that we considered very important is to indicate the assessment of the thymus through radiological images to highlight its variability in shape, size, and anatomical conformation.
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Affiliation(s)
- Rita Rezzani
- Anatomy and Physiopathology Division, Department of Clinical and Experimental Sciences, Viale Europa 11, 25123, Brescia, Italy,
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18
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Lario M, Muñoz L, Ubeda M, Borrero MJ, Martínez J, Monserrat J, Díaz D, Alvarez-Mon M, Albillos A. Defective thymopoiesis and poor peripheral homeostatic replenishment of T-helper cells cause T-cell lymphopenia in cirrhosis. J Hepatol 2013; 59:723-30. [PMID: 23742913 DOI: 10.1016/j.jhep.2013.05.042] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/12/2012] [Revised: 05/09/2013] [Accepted: 05/19/2013] [Indexed: 12/18/2022]
Abstract
BACKGROUND & AIMS Depletion of circulating CD4(+) T-helper (Th) lymphocytes, especially naive Th cells, is common in cirrhosis. Little is known about the pathogenetic mechanisms involved in Th-cell depletion in cirrhosis. We investigated the mechanisms involved in circulating Th-cell lymphopenia in cirrhosis. METHODS Circulating naive and memory Th cells were analyzed by flow cytometry in 60 patients with cirrhosis and 40 sex- and age-matched healthy controls. Thymopoiesis, apoptosis, cell activation, and proliferation were assessed through CD31, annexin-V, HLA-DR and Ki-67 expression, respectively. Lipopolysaccharide (LPS)-binding protein (LBP) and spleen size were measured as indicators of bacterial translocation and splenic pooling, respectively. RESULTS Compared to controls, patients showed reduced numbers of Th cells involving a greater depletion of the naive than memory Th-cell compartment (2.7- vs. 1.5-fold, respectively). Recent thymic emigrants were diminished (p < 0.01), and each patient had a lower number of CD31(+) naive Th cells than the matched-control. Spontaneous and induced apoptosis (Annexin-V(+)) of Th cells was increased in patients. Activated (HLA-DR(+)) and proliferating (Ki-67(+)) memory Th cells were increased in patients (p < 0.01), and they directly correlated with plasma LBP (p < 0.05) and negatively with naive Th cells (p < 0.01), respectively. Naive Th cells were inversely correlated (p < 0.01) with their frequencies of apoptosis and of activated memory Th cells, LBP, and spleen size. On multivariate analysis, defective thymic generation of naive Th cells, increased memory Th-cell activation, and splenomegaly were independently associated with Th-cell depletion. CONCLUSIONS Th-cell immunodeficiency in cirrhosis is explained by a universal defect in thymopoiesis exacerbated by splenic pooling and activation-driven cell-death induced by bacterial translocation.
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Affiliation(s)
- Margaret Lario
- Departamento de Medicina, Universidad de Alcalá, Madrid, Spain
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19
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Romano R, Palamaro L, Fusco A, Giardino G, Gallo V, Del Vecchio L, Pignata C. FOXN1: A Master Regulator Gene of Thymic Epithelial Development Program. Front Immunol 2013; 4:187. [PMID: 23874334 PMCID: PMC3709140 DOI: 10.3389/fimmu.2013.00187] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/25/2013] [Indexed: 11/18/2022] Open
Abstract
T cell ontogeny is a sophisticated process, which takes place within the thymus through a series of well-defined discrete stages. The process requires a proper lympho-stromal interaction. In particular, cortical and medullary thymic epithelial cells (cTECs, mTECs) drive T cell differentiation, education, and selection processes, while the thymocyte-dependent signals allow thymic epithelial cells (TECs) to maturate and provide an appropriate thymic microenvironment. Alterations in genes implicated in thymus organogenesis, including Tbx1, Pax1, Pax3, Pax9, Hoxa3, Eya1, and Six1, affect this well-orchestrated process, leading to disruption of thymic architecture. Of note, in both human and mice, the primordial TECs are yet unable to fully support T cell development and only after the transcriptional activation of the Forkhead-box n1 (FOXN1) gene in the thymic epithelium this essential function is acquired. FOXN1 is a master regulator in the TEC lineage specification in that it down-stream promotes transcription of genes, which, in turn, regulate TECs differentiation. In particular, FOXN1 mainly regulates TEC patterning in the fetal stage and TEC homeostasis in the post-natal thymus. An inborn null mutation in FOXN1 leads to Nude/severe combined immunodeficiency (SCID) phenotype in mouse, rat, and humans. In Foxn1−/− nude animals, initial formation of the primordial organ is arrested and the primordium is not colonized by hematopoietic precursors, causing a severe primary T cell immunodeficiency. In humans, the Nude/SCID phenotype is characterized by congenital alopecia of the scalp, eyebrows, and eyelashes, nail dystrophy, and a severe T cell immunodeficiency, inherited as an autosomal recessive disorder. Aim of this review is to summarize all the scientific information so far available to better characterize the pivotal role of the master regulator FOXN1 transcription factor in the TEC lineage specifications and functionality.
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Affiliation(s)
- Rosa Romano
- Department of Translational Medical Sciences, "Federico II" University , Naples , Italy
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20
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Cermakian N, Lange T, Golombek D, Sarkar D, Nakao A, Shibata S, Mazzoccoli G. Crosstalk between the circadian clock circuitry and the immune system. Chronobiol Int 2013; 30:870-88. [PMID: 23697902 DOI: 10.3109/07420528.2013.782315] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Various features, components, and functions of the immune system present daily variations. Immunocompetent cell counts and cytokine levels present variations according to the time of day and the sleep-wake cycle. Moreover, different immune cell types, such as macrophages, natural killer cells, and lymphocytes, contain a circadian molecular clockwork. The biological clocks intrinsic to immune cells and lymphoid organs, together with inputs from the central pacemaker of the suprachiasmatic nuclei via humoral and neural pathways, regulate the function of cells of the immune system, including their response to signals and their effector functions. Consequences of this include, for example, the daily variation in the response to an immune challenge (e.g., bacterial endotoxin injection) and the circadian control of allergic reactions. The circadian-immune connection is bidirectional, because in addition to this circadian control of immune functions, immune challenges and immune mediators (e.g., cytokines) were shown to have strong effects on circadian rhythms at the molecular, cellular, and behavioral levels. This tight crosstalk between the circadian and immune systems has wide-ranging implications for disease, as shown by the higher incidence of cancer and the exacerbation of autoimmune symptoms upon circadian disruption.
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Affiliation(s)
- Nicolas Cermakian
- Laboratory of Molecular Chronobiology, Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Montreal, Quebec, Canada
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21
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Psychoneuroendocrine interventions aimed at attenuating immunosenescence: a review. Biogerontology 2013; 14:9-20. [DOI: 10.1007/s10522-012-9412-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2012] [Accepted: 12/20/2012] [Indexed: 12/18/2022]
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22
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Geenen V. Presentation of neuroendocrine self in the thymus: a necessity for integrated evolution of the immune and neuroendocrine systems. Ann N Y Acad Sci 2012; 1261:42-8. [PMID: 22823392 DOI: 10.1111/j.1749-6632.2012.06624.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
During evolution, from ancestor thymoids scattered in gill baskets of the lamprey, the first unique thymus appeared in jawed cartilaginous fishes around 450-500 millions years ago, concomitantly or shortly after the emergence of recombinase-dependent adaptive immunity. The major biological function of the thymus is to generate a diverse repertoire of T cell receptors that are self tolerant. The thymus achieves this role by using two complementary and intimately associated mechanisms: apoptotic deletion of T cell clones bearing a TCR with high affinity for self-antigens presented by MHC proteins on thymic epithelial cells (TECs) and dendritic cells (DCs); and generation of self-antigen-specific natural regulatory T (nT(reg)) cells. Moreover, the escape from thymic central self-tolerance plays a primary role in the development of autoimmune diseases that are a significant burden for the quality of life and health-care cost. Our new knowledge in thymus physiology and physiopathology is currently translated into innovative therapeutic strategies against these devastating chronic diseases.
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Affiliation(s)
- Vincent Geenen
- University of Liege, GIGA-Research Center of Immunoendocrinology, Sart Tilman, Belgium.
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23
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Albuquerque AS, Marques JG, Silva SL, Ligeiro D, Devlin BH, Dutrieux J, Cheynier R, Pignata C, Victorino RMM, Markert ML, Sousa AE. Human FOXN1-deficiency is associated with αβ double-negative and FoxP3+ T-cell expansions that are distinctly modulated upon thymic transplantation. PLoS One 2012; 7:e37042. [PMID: 22590644 PMCID: PMC3349657 DOI: 10.1371/journal.pone.0037042] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Accepted: 04/12/2012] [Indexed: 01/03/2023] Open
Abstract
Forkhead box N1 (FOXN1) is a transcription factor crucial for thymic epithelium development and prevention of its involution. Investigation of a patient with a rare homozygous FOXN1 mutation (R255X), leading to alopecia universalis and thymus aplasia, unexpectedly revealed non-maternal circulating T-cells, and, strikingly, large numbers of aberrant double-negative αβ T-cells (CD4negCD8neg, DN) and regulatory-like T-cells. These data raise the possibility that a thymic rudiment persisted, allowing T-cell development, albeit with disturbances in positive/negative selection, as suggested by DN and FoxP3+ cell expansions. Although regulatory-like T-cell numbers normalized following HLA-mismatched thymic transplantation, the αβDN subset persisted 5 years post-transplantation. Involution of thymus allograft likely occurred 3 years post-transplantation based on sj/βTREC ratio, which estimates intrathymic precursor T-cell divisions and, consequently, thymic explant output. Nevertheless, functional immune-competence was sustained, providing new insights for the design of immunological reconstitution strategies based on thymic transplantation, with potential applications in other clinical settings.
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Affiliation(s)
- Adriana S. Albuquerque
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
| | - José G. Marques
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisboa, Portugal
| | - Susana L. Silva
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisboa, Portugal
| | - Dario Ligeiro
- Immunogenetics Laboratory, Centro de Histocompatibilidade do Sul – CHSul, Lisboa, Portugal
| | - Blythe H. Devlin
- Division of Allergy and Immunology, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Jacques Dutrieux
- Institut Cochin, Département Immunologie-Hematologie, Paris, France
- Inserm, U567, Paris, France
- CNRS, UMR 8104, Paris, France
| | - Rémi Cheynier
- Institut Cochin, Département Immunologie-Hematologie, Paris, France
- Inserm, U567, Paris, France
- Université Paris Descartes, Faculté de Médecine René Descartes, UMR-S 8104, Paris, France
- CNRS, UMR 8104, Paris, France
| | - Claudio Pignata
- Pediatric Immunology Unit, Department of Pediatrics, “Federico II” University, Naples, Italy
| | - Rui M. M. Victorino
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- Hospital de Santa Maria, Centro Hospitalar Lisboa Norte, Lisboa, Portugal
| | - M. Louise Markert
- Division of Allergy and Immunology, Department of Pediatrics, Duke University Medical Center, Durham, North Carolina, United States of America
- Department of Immunology, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Ana E. Sousa
- Instituto de Medicina Molecular, Faculdade de Medicina, Universidade de Lisboa, Lisboa, Portugal
- * E-mail:
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Kermani H, Goffinet L, Mottet M, Bodart G, Morrhaye G, Dardenne O, Renard C, Overbergh L, Baron F, Beguin Y, Geenen V, Martens HJ. Expression of the growth hormone/insulin-like growth factor axis during Balb/c thymus ontogeny and effects of growth hormone upon ex vivo T cell differentiation. Neuroimmunomodulation 2012; 19:137-47. [PMID: 22261974 DOI: 10.1159/000328844] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2011] [Accepted: 04/13/2011] [Indexed: 02/02/2023] Open
Abstract
AIMS We address the question of the expression and the role of the growth hormone/insulin-like growth factor (GH/IGF) axis in the thymus. METHODS Using RT-qPCR, the expression profile of various components of the somatotrope GH/IGF axis was measured in different thymic cell types and during thymus embryogenesis in Balb/c mice. The effect of GH on T cell differentiation was explored via thymic organotypic culture. RESULTS Transcription of Gh, Igf1, Igf2 and their related receptors predominantly occurred in thymic epithelial cells (TEC), while a low level of Gh and Igf1r transcription was also evidenced in thymic T cells (thymocytes). Gh, Ghr, Ins2, Igf1, Igf2, and Igfr1 displayed distinct expression profiles depending on the developmental stage. The protein concentrations of IGF-1 and IGF-2 were in accordance with the profile of their gene expression. In fetal thymus organ cultures (FTOC) derived from Balb/c mice, treatment with exogenous GH resulted in a significant increase of double negative CD4-CD8- T cells and CD4+ T cells, together with a decrease in double positive CD4+CD8+ T cells. These changes were inhibited by concomitant treatment with GH and the GH receptor (GHR) antagonist pegvisomant. However, GH treatment also induced a significant decrease in FTOC Gh, Ghr and Igf1 expression. CONCLUSION These data show that the thymotropic properties of the somatotrope GH/IGF-1 axis involve an interaction between exogenous GH and GHR expressed by TEC. Since thymic IGF-1 is not increased by GH treatment, the effects of GH upon T cell differentiation could implicate a different local growth factor or cytokine.
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Affiliation(s)
- Hamid Kermani
- Center of Immunology, Institute of Pathology, University of Liège, CHU-B23, Liège-Sart Tilman, Belgium
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25
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Thymic self-antigen expression for the design of a negative/tolerogenic self-vaccine against type 1 diabetes. Clin Dev Immunol 2011; 2011:349368. [PMID: 21647405 PMCID: PMC3102425 DOI: 10.1155/2011/349368] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 03/08/2011] [Indexed: 01/07/2023]
Abstract
Before being able to react against infectious non-self-antigens, the immune system has to be educated in the recognition and tolerance of neuroendocrine proteins, and this critical process essentially takes place in the thymus. The development of the autoimmune diabetogenic response results from a thymus dysfunction in programming central self-tolerance to pancreatic insulin-secreting islet β cells, leading to the breakdown of immune homeostasis with an enrichment of islet β cell reactive effector T cells and a deficiency of β cell-specific natural regulatory T cells (nTreg) in the peripheral T-lymphocyte repertoire. Insulin-like growth factor 2 (IGF-2) is the dominant member of the insulin family expressed during fetal life by the thymic epithelium under the control of the autoimmune regulator (AIRE) gene/protein. Based on the close homology and cross-tolerance between insulin, the primary T1D autoantigen, and IGF-2, the dominant self-antigen of the insulin family, a novel type of vaccination, so-called “negative/tolerogenic self-vaccination”, is currently developed for prevention and cure of T1D. If this approach were found to be effective for reprogramming immunological tolerance in T1D, it could pave the way for the design of negative self-vaccines against autoimmune endocrine diseases, as well as other organ-specific autoimmune diseases.
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26
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Plana M, Garcia F, Darwich L, Romeu J, López A, Cabrera C, Massanella M, Canto E, Ruiz-Hernandez R, Blanco J, Sánchez M, Gatell JM, Clotet B, Ruiz L, Bofill M. The reconstitution of the thymus in immunosuppressed individuals restores CD4-specific cellular and humoral immune responses. Immunology 2011; 133:318-28. [PMID: 21501161 DOI: 10.1111/j.1365-2567.2011.03442.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Infection with HIV-1 frequently results in the loss of specific cellular immune responses and an associated lack of antibodies. Recombinant growth hormone (rGH) administration reconstitutes thymic tissue and boosts the levels of peripheral T cells, so rGH therapy may be an effective adjuvant through promoting the recovery of lost cellular and T-cell-dependent humoral immune responses in immunosuppressed individuals. To test this concept, we administered rGH to a clinically defined group of HIV-1-infected subjects with defective cellular and serological immune responses to at least one of three commonly employed vaccines (hepatitis A, hepatitis B or tetanus toxoid). Of the original 278 HIV-1-infected patients entering the trial, only 20 conformed to these immunological criteria and were randomized into three groups: Group A (n = 8) receiving rGH and challenged with the same vaccine to which they were unresponsive and Groups B (n = 5) and C (n = 7) who received either rGH or vaccination alone, respectively. Of the eight subjects in Group A, five recovered CD4 cellular responses to vaccine antigen and four of these produced the corresponding antibodies. In the controls, three of the five in group B recovered cellular responses with two producing antibodies, whereas three of the seven in Group C recovered CD4 responses, with only two producing antibodies. Significantly, whereas seven of ten patients receiving rGH treatment in Group A (six patients) and B (one patient) recovered T-cell responses to HIVp24, only two of six in Group C responded similarly. In conclusion, reconstitution of the thymus in immunosuppressed adults through rGH hormone treatment restored both specific antibody and CD4 T-cell responses.
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Affiliation(s)
- Montserrat Plana
- Retrovirology and Viral Immunopathology Laboratory, IDIBAPS, Hospital Clínic, University of Barcelona, Spain
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27
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Britto IMPA, Aguiar-Oliveira MH, Oliveira-Neto LA, Salvatori R, Souza AHO, Araujo VP, Corraini P, Pannuti CM, Romito GA, Pustiglioni FE. Periodontal disease in adults with untreated congenital growth hormone deficiency: a case-control study. J Clin Periodontol 2011; 38:525-31. [PMID: 21488932 DOI: 10.1111/j.1600-051x.2011.01721.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIM The aim of this study was to investigate the possible associations between isolated growth hormone deficiency (IGHD) and periodontal attachment loss (PAL) in adults affected by congenital IGHD. MATERIALS AND METHODS Forty-five previously identified IGHD subjects were eligible for this study. The final study sample comprised 32 cases (gender:20M/12F; age:44.8 ± 17.5) matched for age, gender, diabetes, smoking status and income to 32 controls (non-IGHD subjects). Participants were submitted to a full-mouth clinical examination of six sites per tooth and were interviewed using a structured, written questionnaire. Periodontitis was defined as proximal PAL≥5 mm affecting ≥30% of teeth. RESULTS No significant differences were observed in the percentage of sites with visible plaque between IGHD and non-IGHD subjects (59.4% versus 46.9%, p=0.32). IGHD subjects had significant less supragingival calculus (31.3% versus 59.4%, p=0.02) and more bleeding on probing (71.9% versus 18.8%, p<0.01) than controls. PAL≥5 mm was significantly more prevalent (100% versus 71.9%, p<0.01) and affected more teeth (30.5% versus 6.7%, p<0.01) in cases than in controls. After adjusting for supragingival calculus, IGHD cases had a higher likelihood of having periodontitis than controls (OR=17.4-17.8, 95% CI=2.3-134.9, p=0.004-0.005). CONCLUSION Congenital IGHD subjects have a greater chance of having PAL.
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Affiliation(s)
- Isabella M P Araujo Britto
- Department of Stomatology, Division of Periodontics, School of Dentistry, University of São Paulo, São Paulo, Brazil
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Mottet M, Goffinet L, Beckers A, Bodart G, Morrhaye G, Kermani H, Renard C, Martens H, Geenen V. The role of the thymus in the integrated evolution of the recombinase-dependent adaptive immune response and the neuroendocrine system. Neuroimmunomodulation 2011; 18:314-9. [PMID: 21952683 DOI: 10.1159/000329498] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Before being able to react against infectious non-self-antigens, the immune system has to be educated in recognition and tolerance of neuroendocrine self-proteins. This sophisticated educational process takes place only in the thymus. The development of an autoimmune response directed to neuroendocrine glands has been shown to result from a thymus dysfunction in programming immunological self-tolerance to neuroendocrine-related antigens. This thymus dysfunction leads to a breakdown of immune homeostasis with an enrichment of 'forbidden' self-reactive T cells and a deficiency in self-antigen-specific natural regulatory T cells in the peripheral T lymphocyte repertoire. A large number of neuroendocrine self-antigens are expressed by the thymic epithelium, under the control of the autoimmune regulator (AIRE) gene/protein in the medulla. Based on the close homology and cross-tolerance between thymic type 1 diabetes-related self-antigens and peripheral antigens targeted in β-cells by autoimmunity, a novel type of vaccination is currently developed for the prevention and cure of type 1 diabetes. If this approach were found to be effective in reprogramming immunological tolerance that is absent or broken in this disease, it could pave the way for the design of negative/tolerogenic self-vaccines against other endocrine and organ-specific autoimmune disorders.
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Affiliation(s)
- Marie Mottet
- University of Liege Center of Immunology, Institute of Pathology CHU-B23, Liege-Sart Tilman, Belgium
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Chen Y, Qiao S, Tuckermann J, Okret S, Jondal M. Thymus‐derived glucocorticoids mediate androgen effects on thymocyte homeostasis. FASEB J 2010. [DOI: 10.1096/fj.10.168724] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Yongwen Chen
- Department of Biosciences and NutritionKarolinska Institutet Stockholm Sweden
- Department of Microbiology Tumor, and Cell BiologyKarolinska Institutet Stockholm Sweden
| | - Shengjun Qiao
- Department of Biosciences and NutritionKarolinska Institutet Stockholm Sweden
- Department of Microbiology Tumor, and Cell BiologyKarolinska Institutet Stockholm Sweden
| | - Jan Tuckermann
- Department of Biosciences and NutritionKarolinska Institutet Stockholm Sweden
- Leibnitz Institute for Age Research‐Fritz Lipmann Institute (FLI) Jena Germany
| | - Sam Okret
- Department of Biosciences and NutritionKarolinska Institutet Stockholm Sweden
| | - Mikael Jondal
- Department of Microbiology Tumor, and Cell BiologyKarolinska Institutet Stockholm Sweden
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Castermans E, Hannon M, Dutrieux J, Humblet-Baron S, Seidel L, Cheynier R, Willems E, Gothot A, Vanbellinghen JF, Geenen V, Sandmaier BM, Storb R, Beguin Y, Baron F. Thymic recovery after allogeneic hematopoietic cell transplantation with non-myeloablative conditioning is limited to patients younger than 60 years of age. Haematologica 2010; 96:298-306. [PMID: 20934996 DOI: 10.3324/haematol.2010.029702] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Long-term immune recovery in older patients given hematopoietic cell transplantation after non-myeloablative conditioning remains poorly understood. This prompted us to investigate long-term lymphocyte reconstitution and thymic function in 80 patients given allogeneic peripheral blood stem cells after non-myeloablative conditioning. DESIGN AND METHODS Median age at transplant was 57 years (range 10-71). Conditioning regimen consisted of 2 Gy total body irradiation (TBI) with (n=46) or without (n=20) added fludarabine, 4 Gy TBI with fludarabine (n=6), or cyclophosphamide plus fludarabine (n=8). Stem cell sources were unmanipulated (n=56), CD8-depleted (n=19), or CD34-selected (n=5) peripheral blood stem cells. Immune recovery was assessed by signal-joint T-cell receptor excision circle quantification and flow cytometry. RESULTS Signal-joint T-cell receptor excision circle levels increased from day 100 to one and two years after transplantation in patients under 50 years of age (n=23; P=0.02 and P=0.04, respectively), and in those aged 51-60 years (n=35; P=0.17 and P=0.06, respectively), but not in patients aged over 60 (n=22; P=0.3 and P=0.3, respectively). Similarly, CD4(+)CD45RA(+) (naïve) T-cell counts increased from day 100 to one and two years after transplantation in patients aged 50 years and under 50 (P=0.002 and P=0.02, respectively), and in those aged 51-60 (P=0.4 and P=0.001, respectively), but less so in patients aged over 60 (P=0.3 and P=0.06, respectively). In multivariate analyses, older patient age (P<0.001), extensive chronic GVHD (P<0.001), and prior (resolved) extensive chronic graft-versus-host disease (P=0.008) were associated with low signal-joint T-cell receptor excision circle levels one year or more after HCT. CONCLUSIONS In summary, our data suggest that thymic neo-generation of T cells occurred from day 100 onwards in patients under 60 while signal-joint T-cell receptor excision circle levels remained low for patients aged over 60. Further, chronic graft-versus-host disease had a dramatic impact on thymic function, as observed previously in patients given grafts after myeloablative conditioning.
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Affiliation(s)
- Emilie Castermans
- University of Liège, Department of Hematology, CHU Sart-Tilman, 4000 Liège, Belgium
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Chen Y, Qiao S, Tuckermann J, Okret S, Jondal M. Thymus-derived glucocorticoids mediate androgen effects on thymocyte homeostasis. FASEB J 2010; 24:5043-51. [PMID: 20798244 DOI: 10.1096/fj.10-168724] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Androgens contribute to the involution process of the aging thymus gland. However, molecular mechanisms behind this effect remain largely unknown. We have investigated the influence of testosterone on the ectopic synthesis of glucocorticoids (GCs) in thymocytes, an activity recently shown by us to be important for the homeostatic regulation of these cells. Castration, which leads to a strong increase in thymus tissue and function, was associated with a reduced GC release from thymocytes caused by down-regulated expression of several enzymes involved in GC synthesis, without affecting GC synthesis in the adrenals. Testosterone treatment of castrated male mice reversed these effects, also without affecting adrenal GC synthesis. The effects of testosterone in castrated mice on thymocyte homeostasis and GC release were strongly reduced in mice pretreated with the CYP11B1 enzyme inhibitor metyrapone, acting on the last step in the corticosterone synthesis. The androgen-induced thymic involution was dependent on GC action, because this was completely absent in mice lacking GC receptor (GR) expression specifically in thymocytes. We provide here an unrecognized mechanism how androgens contribute to thymic involution by stimulating local synthesis and release of GCs in the thymus.
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Affiliation(s)
- Yongwen Chen
- Department of Bioscience and Nutrition, Karolinska Institutet, SE-141 83 Huddinge, Stockholm, Sweden.
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Pleiotropic modulation of thymic functions by growth hormone: from physiology to therapy. Curr Opin Pharmacol 2010; 10:434-42. [DOI: 10.1016/j.coph.2010.04.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 04/06/2010] [Indexed: 11/20/2022]
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Rejuvenation of the aging thymus: growth hormone-mediated and ghrelin-mediated signaling pathways. Curr Opin Pharmacol 2010; 10:408-24. [PMID: 20595009 DOI: 10.1016/j.coph.2010.04.015] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2010] [Revised: 04/28/2010] [Accepted: 04/29/2010] [Indexed: 12/20/2022]
Abstract
One of the major fundamental causes for the aging of the immune system is the structural and functional involution of the thymus, and the associated decline in de novo naïve T-lymphocyte output. This loss of naïve T-cell production weakens the ability of the adaptive immune system to respond to new antigenic stimuli and eventually leads to a peripheral T-cell bias to the memory phenotype. While the precise mechanisms responsible for age-associated thymic involution remain unknown, a variety of theories have been forwarded including the loss of expression of various growth factors and hormones that influence the lymphoid compartment and promote thymic function. Extensive studies examining two hormones, namely growth hormone (GH) and ghrelin (GRL), have demonstrated their contributions to thymus biology. In the current review, we discuss the literature supporting a role for these hormones in thymic physiology and age-associated thymic involution and their potential use in the restoration of thymic function in aged and immunocompromised individuals.
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Holländer GA, Krenger W, Blazar BR. Emerging strategies to boost thymic function. Curr Opin Pharmacol 2010; 10:443-53. [PMID: 20447867 DOI: 10.1016/j.coph.2010.04.008] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2010] [Revised: 04/06/2010] [Accepted: 04/06/2010] [Indexed: 11/28/2022]
Abstract
The thymus constitutes the primary lymphoid organ for the generation of T cells. Its function is particularly susceptible to various negative influences ranging from age-related involution to atrophy as a consequence of malnutrition, infection or harmful iatrogenic influences such as chemotherapy and radiation. The loss of regular thymus function significantly increases the risk for infections and cancer because of a restricted capacity for immune surveillance. In recent years, thymus-stimulatory, thymus-regenerative, and thymus-protective strategies have been developed to enhance and repair thymus function in the elderly and in individuals undergoing hematopoietic stem cell transplantation. These strategies include the use of sex steroid ablation, the administration of growth and differentiation factors, the inhibition of p53, and the transfer of T cell progenitors to alleviate the effects of thymus dysfunction and consequent T cell deficiency.
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Affiliation(s)
- Georg A Holländer
- Laboratory of Pediatric Immunology, Department of Biomedicine, University of Basel, The University Children's Hospital (UKBB), Mattenstrasse 28, 4058 Basel, Switzerland.
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Alterations of the systemic environment are the primary cause of impaired B and T lymphopoiesis in telomere-dysfunctional mice. Blood 2009; 115:1481-9. [PMID: 19965646 DOI: 10.1182/blood-2009-08-237230] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
There is growing evidence that telomere dysfunction can contribute to human aging. Telomere dysfunction limits lymphopoiesis in aging telomerase knockout (mTerc(-/-)) mice primarily by the induction of stem cell-extrinsic alterations. The relative contribution of alterations in the stem cell niche and the systemic environment to the impairment of lymphopoiesis in response to telomere dysfunction is currently unknown. This study reveals a minor impact of stem cell-intrinsic defects on the impairment of B and T lymphopoiesis in response to telomere dysfunction. The impairment in B and T lymphopoiesis in aging telomere-dysfunctional mice was mainly due to alterations of the systemic environment. Telomere dysfunction had no significant cell-autonomous effects impairing the function of thymic or bone marrow niches in supporting B and T lymphopoiesis. Moreover, age-related alterations in the cellular composition of the thymic epithelium in telomere-dysfunctional mice were rescued by transplantation of the thymus into a wild-type environment; these rejuvenated thymi supported normal T lymphopoiesis in recipient mice. Together, these data place alterations in the systemic environment on top of the hierarchy of events limiting lymphopoiesis in response to telomere dysfunction.
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