251
|
|
252
|
Kleijwegt FS, Laban S, Duinkerken G, Joosten AM, Koeleman BPC, Nikolic T, Roep BO. Transfer of Regulatory Properties from Tolerogenic to Proinflammatory Dendritic Cells via Induced Autoreactive Regulatory T Cells. THE JOURNAL OF IMMUNOLOGY 2011; 187:6357-64. [DOI: 10.4049/jimmunol.1101638] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
|
253
|
Abstract
The discovery of regulatory T cells (Tregs) as a crucial component of peripheral down-regulation of immunity to self and allogeneic antigens has raised legitimate hope for the development of Treg-based clinical protocols for tolerance to allografts. The present review addresses the question of whether therapeutic Tregs are ready to enter the clinical transplantation arena. In light of recent experimental observations, we will revisit some fundamentals of T cell and Treg biology that stress the need for further studies prior to applications and provide conceptual cues for novel therapeutic approaches.
Collapse
Affiliation(s)
- Christian Leguern
- Transplantation Biology Research Center, Department of Surgery, Massachusetts General Hospital East, Harvard Medical School, Boston, MA 02129, USA.
| |
Collapse
|
254
|
Grigoriadis G, Vasanthakumar A, Banerjee A, Grumont R, Overall S, Gleeson P, Shannon F, Gerondakis S. c-Rel controls multiple discrete steps in the thymic development of Foxp3+ CD4 regulatory T cells. PLoS One 2011; 6:e26851. [PMID: 22066012 PMCID: PMC3204987 DOI: 10.1371/journal.pone.0026851] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2011] [Accepted: 10/05/2011] [Indexed: 12/21/2022] Open
Abstract
The development of natural Foxp3+ CD4 regulatory T cells (nTregs) proceeds via two steps that involve the initial antigen dependent generation of CD25+GITRhiFoxp3−CD4+ nTreg precursors followed by the cytokine induction of Foxp3. Using mutant mouse models that lack c-Rel, the critical NF-κB transcription factor required for nTreg differentiation, we establish that c-Rel regulates both of these developmental steps. c-Rel controls the generation of nTreg precursors via a haplo-insufficient mechanism, indicating that this step is highly sensitive to c-Rel levels. However, maintenance of c-Rel in an inactive state in nTreg precursors demonstrates that it is not required for a constitutive function in these cells. While the subsequent IL-2 induction of Foxp3 in nTreg precursors requires c-Rel, this developmental transition does not coincide with the nuclear expression of c-Rel. Collectively, our results support a model of nTreg differentiation in which c-Rel generates a permissive state for foxp3 transcription during the development of nTreg precursors that influences the subsequent IL-2 dependent induction of Foxp3 without a need for c-Rel reactivation.
Collapse
Affiliation(s)
- George Grigoriadis
- Centre for Immunology, Burnet Institute, Melbourne, Australia
- Australian Centre for Blood Diseases and Department of Clinical Hematology, Monash University, Alfred Medical Research and Education Precinct, Melbourne, Australia
| | | | - Ashish Banerjee
- Centre for Immunology, Burnet Institute, Melbourne, Australia
| | - Raelene Grumont
- Centre for Immunology, Burnet Institute, Melbourne, Australia
| | - Sarah Overall
- Bio21, University of Melbourne, Parkville, Australia
| | - Paul Gleeson
- Bio21, University of Melbourne, Parkville, Australia
| | - Frances Shannon
- The John Curtin School of Medical Research, Australian National University, Canberra City, Australia
| | - Steve Gerondakis
- Centre for Immunology, Burnet Institute, Melbourne, Australia
- Australian Centre for Blood Diseases and Department of Clinical Hematology, Monash University, Alfred Medical Research and Education Precinct, Melbourne, Australia
- Department of Immunology, Monash University, Alfred Medical Research and Education Precinct, Melbourne, Australia
- * E-mail:
| |
Collapse
|
255
|
Kornete M, Piccirillo CA. Critical co-stimulatory pathways in the stability of Foxp3+ Treg cell homeostasis in Type I diabetes. Autoimmun Rev 2011; 11:104-11. [PMID: 21875694 DOI: 10.1016/j.autrev.2011.08.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 08/15/2011] [Indexed: 12/16/2022]
Abstract
Mechanisms of peripheral tolerance maintain a controlled balance between self-tolerance, protective immunity against a spectrum of non-self antigens, and suppressing pathology in various disorders. CD4(+) regulatory T cells (T(reg)) expressing the Foxp3 transcription factor dominantly control the activity and pathological consequences of a variety of effector T cell lineages in various inflammatory settings. This review will focus on recent advances on the roles of B7 family members in regulating Treg cell development, function and homeostasis during tolerance induction and organ-specific autoimmunity.
Collapse
Affiliation(s)
- Mara Kornete
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
| | | |
Collapse
|
256
|
Hinterberger M, Wirnsberger G, Klein L. B7/CD28 in central tolerance: costimulation promotes maturation of regulatory T cell precursors and prevents their clonal deletion. Front Immunol 2011; 2:30. [PMID: 22566820 PMCID: PMC3341949 DOI: 10.3389/fimmu.2011.00030] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2011] [Accepted: 07/14/2011] [Indexed: 12/16/2022] Open
Abstract
According to the “two-step model,” the intrathymic generation of CD4+ regulatory T (Treg) cells segregates into a first, T cell receptor (TCR)-driven phase and a second, cytokine-dependent phase. The initial TCR stimulus gives rise to a CD25+Foxp3− developmental intermediate. These precursors subsequently require cytokine signaling to establish the mature CD25+Foxp3+ Treg cell phenotype. In addition, costimulation via CD28/B7 (CD80/86) axis is important for the generation of a Treg cell repertoire of normal size. Recent data suggest that CD28 or B7 deficient mice lack CD25+Foxp3− Treg cell progenitors. However, these data leave open whether costimulation is also required at subsequent stages of Treg differentiation. Also, the fate of “presumptive” Treg cells carrying a permissive TCR specificity in the absence of costimulation remains to be established. Here, we have used a previously described TCR transgenic model of agonist-driven Treg differentiation in order to address these issues. Intrathymic adoptive transfer of Treg precursors indicated that costimulation is dispensable once the intermediate CD25+Foxp3− stage has been reached. Furthermore, lack of costimulation led to the physical loss of presumptive Treg cells rather than their escape from central tolerance and differentiation into the conventional CD4+ T cell lineage. Our findings suggest that CD28 signaling does not primarily operate through enhancing the TCR signal strength in order to pass the threshold intensity required to initiate Treg cell specification. Instead, costimulation seems to deliver unique and qualitatively distinct signals that coordinately foster the developmental progression of Treg precursors and prevent their negative selection.
Collapse
|
257
|
Lim DG, Park YH, Kim SE, Kim YH, Park CS, Kim SC, Park CG, Han DJ. Aurintricarboxylic acid promotes the conversion of naive CD4+CD25- T cells into Foxp3-expressing regulatory T cells. Int Immunol 2011; 23:583-92. [PMID: 21750147 DOI: 10.1093/intimm/dxr058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Naive peripheral CD4(+)CD25(-) T cells can be converted into Foxp3-expressing regulatory T cells under appropriate stimulation conditions. Considering that continuous exposure to antigens is one of the prerequisites for the differentiation and maintenance of Treg cells, we investigated whether preventing activation-induced cell death while providing continuous TCR stimulation could promote the expression of Foxp3 in murine naive CD4(+) T cells. Among the several anti-apoptotic agents tested, aurintricarboxylic acid (ATA) was found to induce the in vitro conversion of naive CD4(+) T cells into Foxp3(+) Treg cells with suppressive activity. Neutralizing studies with an antibody against transforming growth factor (TGF)-β revealed that ATA requires the presence of TGF-β to induce Foxp3 expression in naive CD4(+)CD25(-) T cells. Although ATA itself did not activate the Smad signaling pathway, it down-regulated the extracellular signal-regulated kinase and mammalian target of rapamycin signaling cascade in activated T cells. Lastly, combined exposure to ATA and TGF-β had a synergistic effect on the rate of induction and maintenance of Foxp3 expression. These results indicate that ATA could be exploited to efficiently prepare inducible regulatory T cells in vitro and may aid in more precisely identifying the specific signaling pathways that drive Foxp3 expression in T cells.
Collapse
Affiliation(s)
- Dong-Gyun Lim
- Department of Surgery, Ulsan University College of Medicine and Asan Medical Center, Seoul, Korea.
| | | | | | | | | | | | | | | |
Collapse
|
258
|
Daniel C, von Boehmer H. Extra-thymically induced regulatory T cells: do they have potential in disease prevention? Semin Immunol 2011; 23:410-7. [PMID: 21724411 DOI: 10.1016/j.smim.2011.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Accepted: 06/07/2011] [Indexed: 01/07/2023]
Abstract
Fopx3(+) Treg safeguard against autoimmune diseases and immune pathology. The extrathymic conversion of naïve T cells into Foxp3(+) regulatory T cells can be achieved in vivo by the delivery of strong-agonist ligands under subimmunogenic conditions. Tolerogenic vaccination with strong-agonist mimetopes of self-antigen to promote self-antigen specific tolerance may represent the most specific and safest means of preventing autoimmunity. This review discusses the requirements for induction of dominant tolerance exerted by Foxp3(+) Tregs in autoimmunity with special emphasis on their impact to interfere with T1D. The future goals are the understanding of self-non-self discrimination at the cellular and molecular level, which should then enable investigators to develop clinical vaccination protocols that specifically interfere with unwanted immune responses.
Collapse
Affiliation(s)
- Carolin Daniel
- Laboratory of Lymphocyte Biology, Department of Cancer Immunology and AIDS, Dana Farber Cancer Institute, Boston, MA 02115, USA
| | | |
Collapse
|
259
|
Wing K, Yamaguchi T, Sakaguchi S. Cell-autonomous and -non-autonomous roles of CTLA-4 in immune regulation. Trends Immunol 2011; 32:428-33. [PMID: 21723783 DOI: 10.1016/j.it.2011.06.002] [Citation(s) in RCA: 143] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2011] [Revised: 05/31/2011] [Accepted: 06/06/2011] [Indexed: 12/31/2022]
Abstract
It is controversial how cytotoxic T lymphocyte antigen (CTLA)-4, a co-inhibitory molecule, contributes to immunological tolerance and negative control of immune responses. Its role as an inducer of cell-intrinsic negative signals to activated effector T cells is well documented. However, there is accumulating evidence that CTLA-4 is essential for the function of naturally occurring Foxp3(+) regulatory T (Treg) cells, which constitutively express the molecule. CTLA-4 deficiency in Foxp3(+) Treg cells indeed impairs their in vivo and in vitro suppressive function. Further, Treg cells can modulate the function of CD80- and CD86-expressing antigen-presenting cells via CTLA-4. Here we discuss how CTLA-4 expression by one T cell can influence the activation of another in a cell non-autonomous fashion and thus control immune responses.
Collapse
Affiliation(s)
- Kajsa Wing
- Section of Medical Inflammation Research, Department of Medical Biophysics and Biochemistry, Karolinska Institute, Stockholm, Sweden
| | | | | |
Collapse
|
260
|
Kuczma M, Lee JR, Kraj P. Connexin 43 signaling enhances the generation of Foxp3+ regulatory T cells. THE JOURNAL OF IMMUNOLOGY 2011; 187:248-57. [PMID: 21642545 DOI: 10.4049/jimmunol.1003785] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Despite their importance for the functioning of the immune system, thymic development and peripheral maintenance of Foxp3(+) regulatory T (T(R)) cells are poorly understood. We have found that connexin 43 (Cx43), expressed by thymic T(R) cells progenitors, supports T(R) development. Mice with deletion of the Cx43 gene induced in T cells produce only few T(R) cells and had increased proportion of activated T cells in the lymph nodes, suggesting impaired peripheral tolerance. Reduction of the T(R) cell numbers was accompanied by increased presence of CD4(+)CD25(+)GITR(+)Foxp3(-) T cells, which did not produce inflammatory cytokines and lost suppressor function. These results strongly argue that we have discovered a novel signaling pathway, controlled by Cx43, that enhances the generation of T(R) cells. We propose that a possible mechanism of Cx43 activity is by regulating Foxp3 expression in T(R) lineage cells.
Collapse
Affiliation(s)
- Michal Kuczma
- Center for Biotechnology and Genomic Medicine, Medical College of Georgia, Augusta, GA 30912, USA
| | | | | |
Collapse
|
261
|
Cell-intrinsic NF-κB activation is critical for the development of natural regulatory T cells in mice. PLoS One 2011; 6:e20003. [PMID: 21625598 PMCID: PMC3097234 DOI: 10.1371/journal.pone.0020003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 04/08/2011] [Indexed: 12/21/2022] Open
Abstract
Background Naturally occurring CD4+CD25+Foxp3+ regulatory T (Treg) cells develop in the thymus and represent a mature T cell subpopulation critically involved in maintaining peripheral tolerance. The differentiation of Treg cells in the thymus requires T cell receptor (TCR)/CD28 stimulation along with cytokine-promoted Foxp3 induction. TCR-mediated nuclear factor kappa B (NF-κB) activation seems to be involved in differentiation of Treg cells because deletion of components of the NF-κB signaling pathway, as well as of NF-κB transcription factors, leads to markedly decreased Treg cell numbers in thymus and periphery. Methodology/Principal Findings To investigate if Treg cell-intrinsic NF-κB activation is required for thymic development and peripheral homeostasis of Treg cells we used transgenic (Tg) mice with thymocyte-specific expression of a stable IκBα mutant to inhibit NF-κB activation solely within the T cell lineage. Here we show that Treg cell-intrinsic NF-κB activation is important for the generation of cytokine-responsive Foxp3− thymic Treg precursors and their further differentiation into mature Treg cells. Treg cell development could neither be completely rescued by the addition of exogenous Interleukin 2 (IL-2) nor by the presence of wild-type derived cells in adoptive transfer experiments. However, peripheral NF-κB activation appears to be required for IL-2 production by conventional T cells, thereby participating in Treg cell homeostasis. Moreover, pharmacological NF-κB inhibition via the IκB kinase β (IKKβ) inhibitor AS602868 led to markedly diminished thymic and peripheral Treg cell frequencies. Conclusion/Significance Our results indicate that Treg cell-intrinsic NF-κB activation is essential for thymic Treg cell differentiation, and further suggest pharmacological NF-κB inhibition as a potential therapeutic approach for manipulating this process.
Collapse
|
262
|
Bour-Jordan H, Esensten JH, Martinez-Llordella M, Penaranda C, Stumpf M, Bluestone JA. Intrinsic and extrinsic control of peripheral T-cell tolerance by costimulatory molecules of the CD28/ B7 family. Immunol Rev 2011; 241:180-205. [PMID: 21488898 PMCID: PMC3077803 DOI: 10.1111/j.1600-065x.2011.01011.x] [Citation(s) in RCA: 296] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Positive and negative costimulation by members of the CD28 family is critical for the development of productive immune responses against foreign pathogens and their proper termination to prevent inflammation-induced tissue damage. In addition, costimulatory signals are critical for the establishment and maintenance of peripheral tolerance. This paradigm has been established in many animal models and has led to the development of immunotherapies targeting costimulation pathways for the treatment of cancer, autoimmune disease, and allograft rejection. During the last decade, the complexity of the biology of costimulatory pathways has greatly increased due to the realization that costimulation does not affect only effector T cells but also influences regulatory T cells and antigen-presenting cells. Thus, costimulation controls T-cell tolerance through both intrinsic and extrinsic pathways. In this review, we discuss the influence of costimulation on intrinsic and extrinsic pathways of peripheral tolerance, with emphasis on members of the CD28 family, CD28, cytotoxic T-lymphocyte antigen-4 (CTLA-4), and programmed death-1 (PD-1), as well as the downstream cytokine interleukin-1 (IL-2).
Collapse
Affiliation(s)
- Hélène Bour-Jordan
- UCSF Diabetes Center, University of California at San Francisco, San Francisco, CA 94143-0400, USA
| | | | | | | | | | | |
Collapse
|
263
|
Gabryšová L, Christensen JR, Wu X, Kissenpfennig A, Malissen B, O'Garra A. Integrated T-cell receptor and costimulatory signals determine TGF-β-dependent differentiation and maintenance of Foxp3+ regulatory T cells. Eur J Immunol 2011; 41:1242-8. [PMID: 21469110 DOI: 10.1002/eji.201041073] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2010] [Revised: 01/14/2011] [Accepted: 02/08/2011] [Indexed: 01/18/2023]
Abstract
Foxp3-expressing Tregs play a non-redundant role in protecting against immune pathologies. Foxp3(+) Tregs can arise intra- and extra-thymically, however, the signals directing their differentiation and maintenance in the periphery are not well understood. We show that stimulation of mouse naïve CD4(+) T cells in vitro with optimal doses of anti-CD3/anti-CD28 resulted in high frequencies of Foxp3(+) T cells via a TGF-β-dependent mechanism. Addition of TGF-β and retinoic acid overcame the inhibition of Foxp3 expression observed during high-strength anti-CD3/anti-CD28 stimulation. Reducing the strength of TCR or costimulatory signals with inhibitors of mammalian target of rapamycin (mTOR) or MEK/ERK signalling also enhanced expression of Foxp3 in a TGF-β-dependent manner. Addition of TGF-β was further required to maintain Foxp3 expression in ex vivo derived Foxp3(+) Tregs upon prolonged anti-CD3/anti-CD28 signalling. Thus, induction/maintenance of Foxp3 expression by TGF-β is modulated by the integrated strength of TCR/costimulatory signals.
Collapse
Affiliation(s)
- Leona Gabryšová
- Division of Immunoregulation, MRC National Institute for Medical Research, London, UK
| | | | | | | | | | | |
Collapse
|
264
|
Shimo Y, Yanai H, Ohshima D, Qin J, Motegi H, Maruyama Y, Hori S, Inoue JI, Akiyama T. TRAF6 directs commitment to regulatory T cells in thymocytes. Genes Cells 2011; 16:437-47. [PMID: 21401811 DOI: 10.1111/j.1365-2443.2011.01500.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Regulatory T cells (Tregs), a subset of CD4(+) helper T cells, are crucial for immunological self-tolerance. Defect in development or function of Tregs results in autoimmune disease in human and mice. Whereas it is known that Tregs mainly develop in the thymus, the molecular mechanism underlying development of Treg is not fully understood. TRAF6-deficient mice showed a severe defect in the Treg development in thymus. In vitro fetal thymic organ culture experiments indicated that the defect is ascribed to the absence of TRAF6 in thymic cells. Moreover, mixed fetal liver transfer experiments revealed that the development of Foxp3(+) cells differentiated from Traf6(-/-) hematopoietic cells was specifically impaired in the thymus, indicating cell-intrinsic requirement for TRAF6 in the Treg development. On the other hand, TRAF6 is not required for the development of conventional CD4(+) T cell. In addition, TGFβ-dependent induction of Foxp3 in CD4(+) T cells in vitro was not impaired by the absence of TRAF6. Overall, our data indicate that TRAF6 plays an essential role on the commitment of immature thymocytes to thymic Tregs in cell-intrinsic fashion.
Collapse
Affiliation(s)
- Yusuke Shimo
- Division of Cellular and Molecular Biology, Institute of Medical Science, University of Tokyo, Minato-ku, Tokyo Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
265
|
Neujahr DC, Larsen CP. Regulatory T cells in lung transplantation--an emerging concept. Semin Immunopathol 2011; 33:117-27. [PMID: 21424593 PMCID: PMC3395059 DOI: 10.1007/s00281-011-0253-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2010] [Accepted: 01/13/2011] [Indexed: 01/11/2023]
Abstract
Lung transplantation represents an option for patients with a variety of end-stage lung diseases. While surgical advances have led to improvements in short-term survival, long-term survival is limited by chronic rejection termed bronchiolitis obliterans syndrome (BOS). A growing body of work is devoted to determining why some patients develop BOS. One avenue of interest that has emerged recently is the role that regulatory T cells (Tregs) may have in protection from BOS. In this review, we will discuss the evidence that Tregs are relevant to outcomes following transplant. We will discuss the relevant animal models, in vitro assays, and human observational studies that support a role for Tregs. We will also explore the interplay between injurious T cells such as Th17 cells and Tregs as well as the effect that additional cell types and chemokines have on the balance between inflammation and regulation. Finally, we will review emerging therapies which may harness the ability of Tregs to lessen the effects of BOS.
Collapse
Affiliation(s)
- David C Neujahr
- Emory University Department of Medicine, Emory University Hospital, Atlanta, GA 30322, USA.
| | | |
Collapse
|
266
|
Lei Y, Ripen AM, Ishimaru N, Ohigashi I, Nagasawa T, Jeker LT, Bösl MR, Holländer GA, Hayashi Y, de Waal Malefyt R, Nitta T, Takahama Y. Aire-dependent production of XCL1 mediates medullary accumulation of thymic dendritic cells and contributes to regulatory T cell development. J Exp Med 2011; 208:383-94. [PMID: 21300913 PMCID: PMC3039864 DOI: 10.1084/jem.20102327] [Citation(s) in RCA: 221] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2010] [Accepted: 01/12/2011] [Indexed: 12/15/2022] Open
Abstract
Dendritic cells (DCs) in the thymus (tDCs) are predominantly accumulated in the medulla and contribute to the establishment of self-tolerance. However, how the medullary accumulation of tDCs is regulated and involved in self-tolerance is unclear. We show that the chemokine receptor XCR1 is expressed by tDCs, whereas medullary thymic epithelial cells (mTECs) express the ligand XCL1. XCL1-deficient mice are defective in the medullary accumulation of tDCs and the thymic generation of naturally occurring regulatory T cells (nT reg cells). Thymocytes from XCL1-deficient mice elicit dacryoadenitis in nude mice. mTEC expression of XCL1, tDC medullary accumulation, and nT reg cell generation are diminished in Aire-deficient mice. These results indicate that the XCL1-mediated medullary accumulation of tDCs contributes to nT reg cell development and is regulated by Aire.
Collapse
Affiliation(s)
- Yu Lei
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
- Key Laboratory of Molecular Biology for Infectious Disease of the People’s Republic of China Ministry of Education, Institute for Viral Hepatitis, The Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010, China
| | - Adiratna Mat Ripen
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
| | - Naozumi Ishimaru
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
| | - Izumi Ohigashi
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
| | - Takashi Nagasawa
- Department of Immunobiology and Hematology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
| | - Lukas T. Jeker
- Laboratory of Pediatric Immunology, Center for Biomedicine, University of Basel and The University Children’s Hospital of Basel, 4058 Basel, Switzerland
| | - Michael R. Bösl
- Transgenic Core Facility, Max-Planck-Institute of Biochemistry, 82152 Martinsried, Germany
| | - Georg A. Holländer
- Laboratory of Pediatric Immunology, Center for Biomedicine, University of Basel and The University Children’s Hospital of Basel, 4058 Basel, Switzerland
| | - Yoshio Hayashi
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
| | | | - Takeshi Nitta
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
| | - Yousuke Takahama
- Division of Experimental Immunology, Institute for Genome Research, Department of Oral Molecular Pathology, Institute of Health Biosciences, University of Tokushima, Tokushima 770-8503, Japan
| |
Collapse
|
267
|
Sharabi A, Mozes E. Harnessing regulatory T cells for the therapy of lupus and other autoimmune diseases. Immunotherapy 2011; 1:385-401. [PMID: 20635958 DOI: 10.2217/imt.09.2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Regulatory T cells (Tregs) maintain immunological homeostasis and prevent autoimmunity. The depletion or functional alteration of Tregs may lead to the development of autoimmune diseases. Tregs consist of different subpopulations of cells, of which CD4(+)CD25(+)Foxp3(+) cells are the most well characterized. However, CD8 Tregs also constitute a major cell population that has been shown to play an important role in autoimmune diseases. This review will discuss the role of Tregs in autoimmune diseases in general and specifically in systemic lupus erythematosus (SLE). SLE is a multisystem autoimmune disease characterized by the production of autoantibodies against nuclear components and by the deposition of immune complexes in the kidneys as well as in other organs. Abnormalities in Tregs were reported in SLE patients and in animal models of the disease. Current treatment of SLE is based on immunosuppressive drugs that are nonspecific and may cause adverse effects. Therefore, the development of novel, specific, side effect-free therapeutic means that will induce functional Tregs is a most desirable goal. Our group and others have designed and utilized tolerogenic peptides that ameliorate SLE manifestations in murine models. Here, we demonstrate the role of CD4 and CD8 Tregs, as well as the interaction between the two subsets of cells and the mechanism of action of the tolerogenic peptides. We also discuss their therapeutic potential for the treatment of SLE.
Collapse
Affiliation(s)
- Amir Sharabi
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | | |
Collapse
|
268
|
Daniel C, Nolting J, von Boehmer H. Mechanisms of self-nonself discrimination and possible clinical relevance. Immunotherapy 2011; 1:631-44. [PMID: 20582233 DOI: 10.2217/imt.09.29] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
This review discusses different mechanisms that result in immunological tolerance, such as intrathymic deletion of immature T cells, intrathymic and extrathymic generation of regulatory T cells, effector mechanisms of regulatory T cells as well as molecular pathways involved in extrathymic generation of regulatory T cells in vivo and in vitro. These molecular mechanisms should enable investigators to develop clinical protocols aiming at the specific prevention of unwanted immune responses, thereby replacing indiscriminate immunosuppression that often has fatal consequences.
Collapse
Affiliation(s)
- Carolin Daniel
- Dana-Farber Cancer Institute, Harvard Medical School, 44 Binney Street, Smith 736, Boston, MA 02115, USA.
| | | | | |
Collapse
|
269
|
Mantel PY, Schmidt-Weber CB. Transforming growth factor-beta: recent advances on its role in immune tolerance. Methods Mol Biol 2011; 677:303-38. [PMID: 20941619 DOI: 10.1007/978-1-60761-869-0_21] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Transforming growth factor (TGF-β1) is a pleiotropic cytokine, secreted by immune and nonhematopoietic cells. TGF-β is involved in many different critical processes, such as embryonal development, cellular maturation and differentiation, wound healing, and immune regulation. It maintains immune homeostasis by acting as a potent immune suppressor through inhibition of proliferation, differentiation, activation, and effector function of immune cells. Paradoxically, depending on the context, it displays proinflammatory properties by being a potent chemoattractant for neutrophils and promoting inflammation. In addition, it does not only induce differentiation into the anti-inflammatory Treg cells, but also into the proinflammatory Th17 and Th9 cells and inhibits Th22 differentiation. TGF-β has been demonstrated to be involved in multiple pathologies. In infections, it protects against collateral damages caused by the immune system, but it also promotes immune evasion and chronic infections. In autoimmune diseases, a TGF-β dysfunction leads to the loss of tolerance to self-antigens. In cancer, TGF-β is a potent inhibitor of cell proliferation and acts as a tumor suppressor at the beginning of tumorogenesis. However, once the cells become resistant to TGF-β, it mainly supports tumor growth and metastasis by promoting immune evasion and angiogenesis. In asthma, it is assumed to promote allergen tolerance, but plays a detrimental role in irreversible remodeling of the airways. Despite the high numbers of TGF-β-targeted pathways, it is a promising drug target for treatment of autoimmunity, cancer, fibrosis, if cell specificity can be achieved.This review summarizes the progresses that have been accomplished on the understanding of TGF-β's signaling in the immune homeostasis and its role in pathogenesis.
Collapse
Affiliation(s)
- Pierre-Yves Mantel
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Harvard University, Boston, MA, USA.
| | | |
Collapse
|
270
|
Strong CD28 costimulation suppresses induction of regulatory T cells from naive precursors through Lck signaling. Blood 2011; 117:3096-103. [PMID: 21245484 DOI: 10.1182/blood-2010-08-301275] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
CD28 costimulation is required for the generation of naturally derived regulatory T cells (nTregs) in the thymus through lymphocyte-specific protein tyrosine kinase (Lck) signaling. However, it is not clear how CD28 costimulation regulates the generation of induced Tregs (iTregs) from naive CD4 T-cell precursors in the periphery. To address this question, we induced iTregs (CD25(+)Foxp3(+)) from naive CD4 T cells (CD25(-)Foxp3(-)) by T-cell receptor stimulation with additional transforming growth factorβ (TGFβ) in vitro, and found that the generation of iTregs was inversely related to the level of CD28 costimulation independently of IL-2. Using a series of transgenic mice on a CD28-deficient background that bears wild-type or mutated CD28 in its cytosolic tail that is incapable of binding to Lck, phosphoinositide 3-kinase (PI3K), or IL-2-inducible T-cell kinase (Itk), we found that CD28-mediated Lck signaling plays an essential role in the suppression of iTreg generation under strong CD28 costimulation. Furthermore, we demonstrate that T cells with the CD28 receptor incapable of activating Lck were prone to iTreg induction in vivo, which contributed to their reduced ability to cause graft-versus-host disease. These findings reveal a novel mechanistic insight into how CD28 costimulation negatively regulates the generation of iTregs, and provide a rationale for promoting T-cell immunity or tolerance by regulating Tregs through targeting CD28 signaling.
Collapse
|
271
|
Soligo M, Camperio C, Caristi S, Scottà C, Del Porto P, Costanzo A, Mantel PY, Schmidt-Weber CB, Piccolella E. CD28 costimulation regulates FOXP3 in a RelA/NF-κB-dependent mechanism. Eur J Immunol 2011; 41:503-13. [PMID: 21268019 DOI: 10.1002/eji.201040712] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 10/18/2010] [Accepted: 11/25/2010] [Indexed: 02/04/2023]
Abstract
The molecular mechanisms whereby CD28 alone or associated with TCR can regulate FOXP3 expression are not understood, although the importance of CD28 as a pivotal regulator of CD4(+) CD25(+) FOXP3(+) T cells is well recognized. We previously demonstrated that unique CD28-induced, NF-κB-dependent signals were sufficient to activate FOXP3 transcription in human CD4(+) CD25(-) T cells; however, the exact mechanisms are currently unknown. In this study, we have identified novel κB-binding sites on FOXP3 gene and demonstrated that CD28 signals mediated FOXP3 trans activation by nuclear translocation of RelA/NF-κB and not of c-Rel. The occupancy of FOXP3 κB-binding sites by RelA dimers that correlated with histone acetylation and recruitment of Pol II were required both to initiate FOXP3 transcription and to control the promoter occupancy by NFAT. Interestingly, knockdown of RelA in CD4(+) CD25(-) T cells stimulated through TCR and CD28 significantly affected FOXP3 expression, confirming that also the transcriptional activation of FOXP3 gene by TCR in the presence of CD28-costimulatory signals is RelA-dependent. In conclusion, these data suggest a new mechanism by which FOXP3 is activated and supports the critical role of CD28 in the regulation of peripheral tolerance.
Collapse
Affiliation(s)
- Marzia Soligo
- Department of Biology and Biotechnology C. Darwin, University Sapienza of Rome, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
272
|
Bar-On L, Birnberg T, Kim KW, Jung S. Dendritic cell-restricted CD80/86 deficiency results in peripheral regulatory T-cell reduction but is not associated with lymphocyte hyperactivation. Eur J Immunol 2011; 41:291-8. [PMID: 21267999 DOI: 10.1002/eji.201041169] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2010] [Revised: 11/03/2010] [Accepted: 11/12/2010] [Indexed: 01/18/2023]
Abstract
Classical DC (cDC) are required for efficient protective T-cell immunity. Moreover, recent data indicate that cDC also play a critical role in mediating homeostatic proliferation and maintenance of peripheral Treg. Here, we corroborate these findings by defining CD80/CD86 costimulation as an essential molecular component required for the cDC-Treg interactions. In contrast to earlier reports, the reduced Treg compartment of mice lacking cDC or selective CD80/86 expression on cDC, as such, did not render the respective animals prone to systemic lymphocyte hyperactivation or autoimmunity. Rather, we provide evidence that elevated immunoglobulin titers, as well as changes in T-cell subset prevalence and activation status are strictly associated with the nonmalignant myeloproliferative disorder triggered by the absence of cDC.
Collapse
Affiliation(s)
- Liat Bar-On
- Department of Immunology, The Weizmann Institute of Science, Rehovot, Israel
| | | | | | | |
Collapse
|
273
|
Daniel C, von Boehmer H. Extrathymic generation of regulatory T cells--chances and challenges for prevention of autoimmune disease. Adv Immunol 2011; 112:177-213. [PMID: 22118409 DOI: 10.1016/b978-0-12-387827-4.00005-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fopx3(+) expressing regulatory T cells (Tregs) function as an indispensable cellular constituent of the immune system by establishing and maintaining immunological self-tolerance. T cell receptor (TCR) ligands of high agonist activity, when applied in vivo under subimmunogenic conditions, convert naive but not activated T cells into stable Tregs expressing Foxp3. Tolerogenic vaccination with strong-agonist mimetopes of self-antigens may function as a safe and highly specific instrument in the prevention of autoimmune disease by promoting self-antigen-specific tolerance. In this review, we address the requirements for generation of dominant tolerance exerted by Foxp3(+) Tregs in autoimmune disease with special focus on type 1 diabetes (T1D). Further understanding of differentiation of T cells into Tregs at the cellular and molecular level will facilitate development of additional tolerogenic vaccination strategies that can be used in prevention as well as therapeutically to combat unwanted immunity.
Collapse
Affiliation(s)
- Carolin Daniel
- Department of Cancer Immunology and AIDS, Laboratory of Lymphocyte Biology, Dana Farber Cancer Institute, Boston, Massachusetts, USA
| | | |
Collapse
|
274
|
Abstract
The development of regulatory T (Treg) cells is essential for the maintenance of immune tolerance and homeostasis. Here, we review recent studies that have advanced our understanding of Treg cell differentiation. In the thymus, TCR specificity to self-antigen appears to be a primary determinant for Treg cell lineage commitment, with c-Rel being an important factor that links T cell receptor (TCR) engagement and Foxp3 expression, along with cytokines and costimulatory molecules. It is also clear that postthymic events shape the peripheral Treg cell population. This includes preferential maintenance of Treg cells specific to self-antigens presented in the periphery, as well as the de novo generation of Treg cells from conventional Foxp3(-) T cells. The process of peripheral Treg cell differentiation shares some features with thymic Treg cell development, but there are notable differences. Together, thymic and peripheral Treg cell differentiation appear to generate an "imprint" of both self- and foreign antigens in the peripheral Treg cell population to provide dominant tolerance.
Collapse
Affiliation(s)
- Hyang-Mi Lee
- Department of Internal Medicine, Division of Rheumatology, Washington University in St. Louis, St. Louis, Missouri, USA
| | | | | |
Collapse
|
275
|
Lio CWJ, Hsieh CS. Becoming self-aware: the thymic education of regulatory T cells. Curr Opin Immunol 2010; 23:213-9. [PMID: 21146972 DOI: 10.1016/j.coi.2010.11.010] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2010] [Revised: 11/22/2010] [Accepted: 11/23/2010] [Indexed: 12/21/2022]
Abstract
The generation of Foxp3(+) regulatory T (Treg) cells in the thymus is essential for immune homeostasis. In the past several years, substantial progress has been made in understanding the mechanisms by which a minor portion of developing thymocytes are selected to become Treg cells. Although previously controversial, recent data support the importance of TCR specificity as a primary determinant for selecting self-reactive thymocytes to become Treg cells in a multi-step process involving cytokines, co-stimulatory molecules, and a variety of antigen-presenting cells. Importantly, the antigenic niche for Treg cell development appears to be typically quite small, implying the recognition of tissue-specific, rather than ubiquitous, self-antigens. Finally, it appears that an NF-κB transcription factor, c-Rel, may be the link between TCR recognition and the induction of Foxp3 expression, which is required for the function and stability of the natural Treg cell population.
Collapse
Affiliation(s)
- Chan-Wang J Lio
- Department of Medicine, Division of Rheumatology, Washington University School of Medicine, St. Louis, MO, USA
| | | |
Collapse
|
276
|
Beyer M, Schultze JL. Plasticity of T(reg) cells: is reprogramming of T(reg) cells possible in the presence of FOXP3? Int Immunopharmacol 2010; 11:555-60. [PMID: 21115121 DOI: 10.1016/j.intimp.2010.11.024] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 11/11/2010] [Accepted: 11/15/2010] [Indexed: 01/01/2023]
Abstract
Regulatory T cells (T(reg) cells) are involved in self tolerance, immune homeostasis, prevention of autoimmunity, and suppression of immunity to pathogens or tumors. The forkhead transcription factor FOXP3 is essential for T(reg)-cell development and function as mutations in FOXP3 cause severe autoimmune diseases in mice and humans. Over the last years it has been postulated that FOXP3 expression in T(reg) prevents effector T-cell (T(effector)-cell) lineage commitment, yet several recent studies suggest that the co-existence of effector and regulatory T-cell programs can occur and might help to enable T(reg) cells with properties necessary to exert their function in peripheral tissues. Furthermore, downregulation of FOXP3 in the periphery might help T(reg) cells to lose suppressive functions and gain memory properties with specificity for self-antigens and an effector phenotype including the ability to produce IFN-γ and IL-17. This plasticity might have an impact on their reactivity towards autoimmunity as well as tumors or infections.
Collapse
Affiliation(s)
- Marc Beyer
- LIMES-Institute, Laboratory for Genomics and Immunoregulation, University of Bonn, Carl-Troll-Str. 31, D-53115 Bonn, Germany.
| | | |
Collapse
|
277
|
Abstract
The suppressive/immunomodulatory function of CD4(+)CD25(+)FOXP3(+) regulatory T (Treg) cells is crucial for the maintenance of immune homeostasis, which helps to prevent autoimmunity and reduce the inflammation induced by pathogens and environmental insults. This review summarizes the current knowledge on the types and mechanisms of action of Treg cells and their role in the immune tolerance to self-antigens, with a particular focus on naturally occurring Treg cells.
Collapse
Affiliation(s)
- Elaine V Lourenço
- Department of Medicine, University of California Los Angeles, Los Angeles, CA 90095-1670, USA
| | | |
Collapse
|
278
|
Park SG, Mathur R, Long M, Hosh N, Hao L, Hayden MS, Ghosh S. T regulatory cells maintain intestinal homeostasis by suppressing γδ T cells. Immunity 2010; 33:791-803. [PMID: 21074460 DOI: 10.1016/j.immuni.2010.10.014] [Citation(s) in RCA: 145] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2010] [Revised: 07/13/2010] [Accepted: 10/27/2010] [Indexed: 12/16/2022]
Abstract
Immune tolerance against enteric commensal bacteria is important for preventing intestinal inflammation. Deletion of phosphoinositide-dependent protein kinase 1 (Pdk1) in T cells via Cd4-Cre induced chronic inflammation of the intestine despite the importance of PDK1 in T cell activation. Analysis of colonic intraepithelial lymphocytes of PDK1-deficient mice revealed markedly increased CD8α(+) T cell receptor (TCR)γδ(+) T cells, including an interleukin-17 (IL-17)-expressing population. TCRγδ(+) T cells were responsible for the inflammatory colitis as shown by the fact that deletion of Tcrd abolished spontaneous colitis in the PDK1-deficient mice. This dysregulation of intestinal TCRγδ(+) T cells was attributable to a reduction in the number and functional capacity of PDK1-deficient T regulatory (Treg) cells. Adoptive transfer of wild-type Treg cells abrogated the spontaneous activation and proliferation of intestinal TCRγδ(+) T cells observed in PDK1-deficient mice and prevented the development of colitis. Therefore, suppression of intestinal TCRγδ(+) T cells by Treg cells maintains enteric immune tolerance.
Collapse
Affiliation(s)
- Sung-Gyoo Park
- Department of Microbiology & Immunology, Columbia University, College of Physicians & Surgeons, New York, NY 10032, USA
| | | | | | | | | | | | | |
Collapse
|
279
|
Regulatory T-cell differentiation versus clonal deletion of autoreactive thymocytes. Immunol Cell Biol 2010; 89:45-53. [PMID: 21042335 DOI: 10.1038/icb.2010.123] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The concept of clonal deletion of immune cells that carry an autoreactive antigen receptor was a central prediction of Burnet's clonal selection theory. A series of classical experiments in the late 1980s revealed that certain immature thymocytes upon encounter of 'self' are indeed removed from the T-cell repertoire before their release into the blood circulation. A second essential cornerstone of immunological tolerance, not anticipated by Burnett, has more recently surfaced through the discovery of Foxp3(+) regulatory T cells (Treg). Intriguingly, it appears that the expression of an autoreactive T-cell receptor is a shared characteristic of T cells that are subject to clonal deletion as well as of those deviated into the Treg lineage. This is all the more striking as Treg differentiation for the most part branches off from mainstream CD4T cell development during thymocyte maturation in the thymus, that is, it may neither temporally nor spatially be separated from clonal deletion. This raises the question of how an apparently identical stimulus, namely the encounter of 'self' during thymocyte development, can elicit fundamentally different outcomes such as apoptotic cell death on the one hand or differentiation into a highly specialized T-cell lineage on the other hand. Here, we will review the T-cell intrinsic and extrinsic factors that have been implicated in intrathymic Treg differentiation and discuss how these parameters may determine whether an autoreactive major histocompatibility complex class II-restricted thymocyte is deviated into the Treg lineage or subject to clonal deletion.
Collapse
|
280
|
Yuan FL, Li X, Lu WG, Xu RS, Zhao YQ, Li CW, Li JP, Chen FH. Regulatory T cells as a potent target for controlling bone loss. Biochem Biophys Res Commun 2010; 402:173-6. [PMID: 20920469 DOI: 10.1016/j.bbrc.2010.09.120] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 09/28/2010] [Indexed: 01/02/2023]
Abstract
Metabolic bone diseases, such as rheumatoid arthritis (RA) and osteoporosis, affect hundreds and millions of people worldwide leading causes of long-term pain and disability. Effective clinical treatment for bone destruction in bone diseases is lacking because the knowledge about molecular mechanisms leading to bone destruction are incompletely understood. Recently, it has been confirmed that regulatory T cells (Tregs) play a crucial role in suppressing the immune response in the pathogenesis of various autoimmune diseases. In vitro, Tregs directly inhibit osteoclasts and differentiation and function. In mice, the injection of Tregs into the TNF transgenic results in enhanced systemic bone density. In addition, it has been shown that increase of Tregs numbers by overexpressing the FoxP3 is effective in the prevention of local and systemic bone destruction. In vivo treatment with anti-CD28 superagonist antibody leading to a stronger increase in Tregs numbers protect against TNF-a-induced bone loss in TNF-transgenic mice. In agreement, Tregs can control ovariectomy-induced bone loss in FoxP3-transgenic mice. In this paper, we will briefly discuss the biological features of Tregs and summarize recent advances on the role of Tregs in the pathogenesis and treatment of bone loss in metabolic bone diseases.
Collapse
Affiliation(s)
- Feng-Lai Yuan
- The Third Hospital Affiliated to Nantong University, Wuxi, Jiangsu 214041, China.
| | | | | | | | | | | | | | | |
Collapse
|
281
|
Mouly E, Chemin K, Nguyen HV, Chopin M, Mesnard L, Leite-de-Moraes M, Burlen-defranoux O, Bandeira A, Bories JC. The Ets-1 transcription factor controls the development and function of natural regulatory T cells. ACTA ACUST UNITED AC 2010; 207:2113-25. [PMID: 20855499 PMCID: PMC2947068 DOI: 10.1084/jem.20092153] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Regulatory T cells (T reg cells) constitute a population of CD4(+) T cells that limits immune responses. The transcription factor Foxp3 is important for determining the development and function of T reg cells; however, the molecular mechanisms that trigger and maintain its expression remain incompletely understood. In this study, we show that mice deficient for the Ets-1 transcription factor (Ets-1(-/-)) developed T cell-mediated splenomegaly and systemic autoimmunity that can be blocked by functional wild-type T reg cells. Spleens of Ets-1(-/-) mice contained mostly activated T cells, including Th2-polarized CD4(+) cells and had reduced percentages of T reg cells. Splenic and thymic Ets-1(-/-) T reg cells expressed low levels of Foxp3 and displayed the CD103 marker that characterizes antigen-experienced T reg cells. Thymic development of Ets-1(-/-) T reg cells appeared intrinsically altered as Foxp3-expressing cells differentiate poorly in mixed fetal liver reconstituted chimera and fetal thymic organ culture. Ets-1(-/-) T reg cells showed decreased in vitro suppression activity and did not protect Rag2(-/-) hosts from naive T cell-induced inflammatory bowel disease. Furthermore, in T reg cells, Ets-1 interacted with the Foxp3 intronic enhancer and was required for demethylation of this regulatory sequence. These data demonstrate that Ets-1 is required for the development of natural T reg cells and suggest a role for this transcription factor in the regulation of Foxp3 expression.
Collapse
Affiliation(s)
- Enguerran Mouly
- EA3963, Université Paris 7 Denis Diderot, Institut National de la Santé et de la Recherche Médicale, Institut Fédératif de Recherche 105, Institut Universitaire d'Hématologie, 75475 Paris, France
| | | | | | | | | | | | | | | | | |
Collapse
|
282
|
Malek TR, Castro I. Interleukin-2 receptor signaling: at the interface between tolerance and immunity. Immunity 2010; 33:153-65. [PMID: 20732639 DOI: 10.1016/j.immuni.2010.08.004] [Citation(s) in RCA: 571] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2010] [Indexed: 12/12/2022]
Abstract
Interleukin-2 receptor (IL-2R) signaling regulates tolerance and immunity. Here, we review recent work concerning the structure, signaling, and function of the IL-2R, emphasizing the contribution of IL-2 for T cell-dependent activity in vivo. IL-2R signaling influences two discrete aspects of immune responses by CD8(+) T cells, terminal differentiation of effector cells in primary responses, and aspects of memory recall responses. IL-2 also delivers essential signals for thymic development of regulatory T (Treg) cells and later to promote their homeostasis and function. Each of these outcomes on T effector and Treg cells requires distinct amounts of IL-2R signaling, with low IL-2R signaling sufficient for many key aspects of Treg cells. Thus, tolerance is readily maintained and favored with limited IL-2.
Collapse
Affiliation(s)
- Thomas R Malek
- Department of Microbiology and Immunology, Miller School of Medicine, University of Miami, PO Box 01960, Miami, FL 33101, USA.
| | | |
Collapse
|
283
|
Román E, Shino H, Qin FXF, Liu YJ. Cutting edge: Hematopoietic-derived APCs select regulatory T cells in thymus. THE JOURNAL OF IMMUNOLOGY 2010; 185:3819-23. [PMID: 20802149 DOI: 10.4049/jimmunol.0900665] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Recognition of self-peptide-MHC complexes by high-affinity TCRs and CD28 signaling are critical for the development of forkhead-winged helix box transcription factor 3(+) regulatory T cells (Tregs) in thymus. However, the type of APCs that are responsible for selecting Tregs has remained unclear. To dissect the role of hematopoietic-derived APCs (HCs) and thymic epithelial cells (TECs) in Treg selection, we constructed bone marrow chimeras with disrupted CD28/B7 signaling in the HC or TEC compartment and analyzed the generation of Tregs in the thymus. We found that both HCs and TECs were independently able to fully reconstitute the Treg population in the thymus of bone marrow chimeras. In addition, Treg selection requires the TCR signal and CD28 costimulation presented in cis on the same APC type in vivo. This study demonstrates a new role, to our knowledge, for HCs in the development of Tregs in thymus.
Collapse
Affiliation(s)
- Eulogia Román
- Department of Immunology, University of Texas, MD Anderson Cancer Center, Houston, TX 77030, USA.
| | | | | | | |
Collapse
|
284
|
CD28 exerts protective and detrimental effects in a pulmonary model of paracoccidioidomycosis. Infect Immun 2010; 78:4922-35. [PMID: 20713624 DOI: 10.1128/iai.00297-10] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
T-cell immunity has been claimed as the main immunoprotective mechanism against Paracoccidioides brasiliensis infection, the most important fungal infection in Latin America. As the initial events that control T-cell activation in paracoccidioidomycosis (PCM) are not well established, we decided to investigate the role of CD28, an important costimulatory molecule for the activation of effector and regulatory T cells, in the immunity against this pulmonary pathogen. Using CD28-deficient (CD28(-/-)) and normal wild-type (WT) C57BL/6 mice, we were able to demonstrate that CD28 costimulation determines in pulmonary paracoccidioidomycosis an early immunoprotection but a late deleterious effect associated with impaired immunity and uncontrolled fungal growth. Up to week 10 postinfection, CD28(-/-) mice presented increased pulmonary and hepatic fungal loads allied with diminished production of antibodies and pro- and anti-inflammatory cytokines besides impaired activation and migration of effector and regulatory T (Treg) cells to the lungs. Unexpectedly, CD28-sufficient mice progressively lost the control of fungal growth, resulting in an increased mortality associated with persistent presence of Treg cells, deactivation of inflammatory macrophages and T cells, prevalent presence of anti-inflammatory cytokines, elevated fungal burdens, and extensive hepatic lesions. As a whole, our findings suggest that CD28 is required for the early protective T-cell responses to P. brasiliensis infection, but it also induces the expansion of regulatory circuits that lately impair adaptive immunity, allowing uncontrolled fungal growth and overwhelming infection, which leads to precocious mortality of mice.
Collapse
|
285
|
Natarajan S, Thomson AW. Tolerogenic dendritic cells and myeloid-derived suppressor cells: potential for regulation and therapy of liver auto- and alloimmunity. Immunobiology 2010; 215:698-703. [PMID: 20605054 DOI: 10.1016/j.imbio.2010.05.024] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Accepted: 05/20/2010] [Indexed: 02/07/2023]
Abstract
Organ transplantation is now established as an accepted treatment for end-stage liver disease, acute fulminant hepatic liver failure and hepatocellular carcinoma. While early graft acceptance rates have increased markedly due to improved immunosuppressive drug regimens, rates of late graft failure remain largely unchanged. Recent findings suggest that in addition to alloimmunity, chronic rejection of liver allografts may also reflect de novo autoimmune hepatitis or recurrence of pre-existing hepatic autoimmune disease. Dendritic cell (DC)- based therapy is a promising experimental approach to promotion of transplant tolerance and the treatment of autoimmune diseases. Newly emerging evidence also demonstrates the potential efficacy of myeloid-derived suppressor cells (MDSC) in the antigen (Ag)-specific regulation of T-cell responses. Herein, we discuss current understanding of liver autoimmunity post-transplantation, along with current approaches for the development of tolerogenic DC, and the potential use of MDSC for the development of stable, Ag-specific tolerance.
Collapse
Affiliation(s)
- Sudha Natarajan
- Starzl Transplantation Institute, Department of Surgery, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA
| | | |
Collapse
|
286
|
Abstract
CD28 costimulation regulates a wide range of cellular processes, from proliferation and survival to promoting the differentiation of specialized T-cell subsets. Since first being identified over 20 years ago, CD28 has remained a subject of intense study because of its profound consequences on T cell function and its potential for therapeutic manipulation. In this review we highlight the signaling cascades initiated by the major signaling motifs in CD28, focusing on PI-3 kinase-dependent and -independent pathways and how these are linked to specific cellular outcomes. Recent studies using gene targeted knockin mice have clarified the relative importance of these motifs on in vivo immune responses; however, much remains to be elucidated. Understanding the mechanism behind costimulation holds great potential for development of new clinically relevant reagents, a fact beginning to be realized with the advent of drugs that prevent CD28 ligation and signaling.
Collapse
Affiliation(s)
- Jonathan S Boomer
- Department of Internal Medicine, Washington University School of Medicine, St Louis, Missouri 63110, USA
| | | |
Collapse
|
287
|
Abstract
FOXP3 is a transcription factor necessary and sufficient for induction of the immunosuppressive functions in regulatory T lymphocytes. Its expression was first considered as specific of this cell type, but FOXP3 can also be transiently expressed in T-cell antigen receptor-activated human nonregulatory T cells. Recent data indicate that FOXP3 is also expressed by some nonlymphoid cells, in which it can repress various oncogenes that are restored following FOXP3 deletion or mutation. This review summarizes major advances in (1) the understanding of Foxp3 functions in human regulatory T cells, (2) the prognostic significance of Foxp3-expressing T cells in human malignancies and (3) the significance of Foxp3 expression in human tumor cells.
Collapse
|
288
|
Ouyang W, Beckett O, Ma Q, Li MO. Transforming growth factor-beta signaling curbs thymic negative selection promoting regulatory T cell development. Immunity 2010; 32:642-53. [PMID: 20471291 DOI: 10.1016/j.immuni.2010.04.012] [Citation(s) in RCA: 194] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2010] [Revised: 02/24/2010] [Accepted: 03/23/2010] [Indexed: 12/15/2022]
Abstract
Thymus-derived naturally occurring regulatory T (nTreg) cells are necessary for immunological self-tolerance. nTreg cell development is instructed by the T cell receptor and can be induced by agonist antigens that trigger T cell-negative selection. How T cell deletion is regulated so that nTreg cells are generated is unclear. Here we showed that transforming growth factor-beta (TGF-beta) signaling protected nTreg cells and antigen-stimulated conventional T cells from apoptosis. Enhanced apoptosis of TGF-beta receptor-deficient nTreg cells was associated with high expression of proapoptotic proteins Bim, Bax, and Bak and low expression of the antiapoptotic protein Bcl-2. Ablation of Bim in mice corrected the Treg cell development and homeostasis defects. Our results suggest that nTreg cell commitment is independent of TGF-beta signaling. Instead, TGF-beta promotes nTreg cell survival by antagonizing T cell negative selection. These findings reveal a critical function for TGF-beta in control of autoreactive T cell fates with important implications for understanding T cell self-tolerance mechanisms.
Collapse
Affiliation(s)
- Weiming Ouyang
- Immunology Program, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
| | | | | | | |
Collapse
|
289
|
Leung S, Liu X, Fang L, Chen X, Guo T, Zhang J. The cytokine milieu in the interplay of pathogenic Th1/Th17 cells and regulatory T cells in autoimmune disease. Cell Mol Immunol 2010; 7:182-9. [PMID: 20383174 PMCID: PMC4002916 DOI: 10.1038/cmi.2010.22] [Citation(s) in RCA: 165] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 03/08/2010] [Accepted: 03/12/2010] [Indexed: 12/12/2022] Open
Abstract
The propagation and regulation of an immune response is driven by a network of effector and regulatory T (Treg) cells. The interplay of effector T and Treg cells determines the direction of the immune response towards inflammation or its resolution in an autoimmune disease setting. In autoimmune diseases, this interplay shifts the balance in favor of the development of autoreactive effector T cells, resulting in inflammatory pathology. The objective of an effective therapeutic approach for autoimmune disease is to restore this balance. In this review, we describe the characteristics and development of pathogenic T helper 1 (Th1) and Th17 cells and the beneficial Treg cells in autoimmune diseases and the crucial roles of the cytokine milieu in influencing the balance of these T-cell subsets. Given the importance of cytokines, we discuss current immunotherapeutic strategies using cytokine or cytokine receptor antibodies for the treatment of autoimmune diseases.
Collapse
Affiliation(s)
- Stewart Leung
- Department of Neuroimmunology, GlaxoSmithKline Research and Development Center, Zhangjiang Pudong, Shanghai, China
| | | | | | | | | | | |
Collapse
|
290
|
Mougiakakos D, Choudhury A, Lladser A, Kiessling R, Johansson CC. Regulatory T cells in cancer. Adv Cancer Res 2010; 107:57-117. [PMID: 20399961 DOI: 10.1016/s0065-230x(10)07003-x] [Citation(s) in RCA: 278] [Impact Index Per Article: 19.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
At the present time, regulatory T cells (Tregs) are an integral part of immunology but the route from discovery of "suppressive" lymphocytes in the 1980s to the current established concept of Tregs almost 20 years later has been a rollercoaster ride. Tregs are essential for maintaining self-tolerance as defects in their compartment lead to severe autoimmune diseases. This vitally important function exists alongside the detrimental effects on tumor immunosurveillance and antitumor immunity. Beginning with the identification of CD4(+)CD25(+) Tregs in 1995, the list of Treg subsets, suppressive mechanisms, and knowledge about their various origins is steadily growing. Increase in Tregs within tumors and circulation of cancer patients, observed in early studies, implied their involvement in pathogenesis and disease progression. Several mechanisms, ranging from proliferation to specific trafficking networks, have been identified to account for their systemic and/or local accumulation. Since various immunotherapeutic approaches are being utilized for cancer therapy, various strategies to overcome the antagonistic effects exerted by Tregs are being currently explored. An overview on the biology of Tregs present in cancer patients, their clinical impact, and methods for modulating them is given in this review. Despite the extensive studies on Tregs in cancer many questions still remain unanswered. Even the paradigm that Tregs generally are disadvantageous for the control of malignancies is now under scrutiny. Insight into the specific role of Tregs in different types of neoplasias is the key for targeting them in a way that is beneficial for the clinical outcome.
Collapse
Affiliation(s)
- Dimitrios Mougiakakos
- Department of Oncology and Pathology, Karolinska University Hospital, Cancer Center Karolinska R8:01, Stockholm, Sweden
| | | | | | | | | |
Collapse
|
291
|
Lio CWJ, Dodson LF, Deppong CM, Hsieh CS, Green JM. CD28 facilitates the generation of Foxp3(-) cytokine responsive regulatory T cell precursors. THE JOURNAL OF IMMUNOLOGY 2010; 184:6007-13. [PMID: 20421644 DOI: 10.4049/jimmunol.1000019] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The T cell costimulatory molecule CD28 plays an important role in the thymic generation of Foxp3(+) regulatory T cells (Tregs) essential for the maintenance of self-tolerance. In this study, we show that a cell-intrinsic signal from CD28 is involved in the generation of cytokine-responsive Foxp3(-) precursors using studies of mixed bone marrow chimeras as well as TCR-specific generation of Foxp3(+) cells using intrathymic transfer of TCR-transgenic thymocytes expressing a natural Treg TCR. Contrary to a previous report, the analysis of CD28 mutant knockin mice revealed that this cell-intrinsic signal is only partially dependent on the Lck-binding PYAP motif. Surprisingly, even though the absence of CD28 resulted in a 6-fold decrease in thymic Tregs, the TCR repertoires of CD28-deficient and sufficient cells were largely overlapping. Thus, these data suggest that CD28 does not operate by markedly enlarging the repertoire of TCRs available for Treg development, but rather by improving the efficiency of Treg development of thymocytes expressing natural Treg TCRs.
Collapse
Affiliation(s)
- Chan-Wang J Lio
- Division of Rheumatology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | | | | | | | |
Collapse
|
292
|
Deenick EK, Elford AR, Pellegrini M, Hall H, Mak TW, Ohashi PS. c-Rel but not NF-kappaB1 is important for T regulatory cell development. Eur J Immunol 2010; 40:677-81. [PMID: 20082358 DOI: 10.1002/eji.201040298] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Regulatory T (Treg) cells are crucial for maintaining peripheral tolerance and controlling T-cell responses. The generation of Treg in the thymus requires TCR triggering and CD28 costimulation. Engagement of these receptors induces a number of signalling pathways, including the activation of NF-kappaB via PKCtheta and the Bcl-10/CARMA1/MALT complex. Previous studies have shown that PKCtheta, Bcl-10 and CARMA1 are important for Treg development. It is unclear, however, whether different members of the NF-kappaB family contribute to Treg development or homeostasis. In this study, we show that Treg numbers are reduced in the absence of c-Rel but not NF-kappaB1 (p50). Furthermore, using mixed bone marrow chimeras from WT and KO animals, we demonstrate that the requirement for PKCtheta, Bcl-10 and c-Rel is T-cell intrinsic, and cannot be rescued by the presence of WT cells. Therefore, c-Rel and NF-kappaB1 have differential roles in Treg development.
Collapse
Affiliation(s)
- Elissa K Deenick
- Campbell Family Institute for Breast Cancer Research, Ontario Cancer Institute, Toronto, Ont., Canada
| | | | | | | | | | | |
Collapse
|
293
|
Haque R, Lei F, Xiong X, Wu Y, Song J. FoxP3 and Bcl-xL cooperatively promote regulatory T cell persistence and prevention of arthritis development. Arthritis Res Ther 2010; 12:R66. [PMID: 20384988 PMCID: PMC2888221 DOI: 10.1186/ar2983] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Revised: 02/16/2010] [Accepted: 04/12/2010] [Indexed: 12/17/2022] Open
Abstract
INTRODUCTION Forkhead box p3 (FoxP3)-expressing regulatory T cells (Tregs) have been clearly implicated in the control of autoimmune disease in murine models. In addition, ectopic expression of FoxP3 conveys a Treg phenotype to CD4(+) T cells, lending itself to therapeutic use in the prevention of rheumatoid arthritis (RA). In this study, we generated therapeutically active Tregs with an increased life span and hence greater therapeutic potential. METHODS We used retrovirus-mediated transduction to introduce FoxP3 or FoxP3 with anti-apoptotic Bcl-2 family molecule Bcl-xL linked by a 2A picornavirus self-cleaving peptide into CD4(+) T cells to generate Tregs. In addition, by using in vitro functional analyses and adoptive immunotherapy in a murine model of RA, we demonstrated that these Tregs were highly reactive. RESULTS We found that CD4(+) T cells expressing both FoxP3 and Bcl-xL were able to differentiate into functional Tregs, which have a long-term survival advantage over cells transduced with FoxP3 alone. In an in vivo murine model, adoptive transfer of Tregs expressing both FoxP3 and Bcl-xL demonstrated more effective suppression of RA than CD4(+) T cells expressing FoxP3 alone. CONCLUSIONS FoxP3 and Bcl-xL can cooperatively promote the differentiation and persistence of Tregs, with the capacity to prevent arthritis. Our results provide a novel approach for generating highly reactive Tregs for augmenting cellular immunotherapy for autoimmune disease.
Collapse
MESH Headings
- Animals
- Arthritis, Experimental/genetics
- Arthritis, Experimental/immunology
- Arthritis, Experimental/prevention & control
- Arthritis, Rheumatoid/genetics
- Arthritis, Rheumatoid/immunology
- Arthritis, Rheumatoid/prevention & control
- Forkhead Transcription Factors/genetics
- Immunotherapy, Adoptive
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Inbred DBA
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/pathology
- Transduction, Genetic
- bcl-X Protein/genetics
Collapse
Affiliation(s)
- Rizwanul Haque
- Department of Microbiology & Immunology and Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Fengyang Lei
- Department of Microbiology & Immunology and Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Xiaofang Xiong
- Department of Microbiology & Immunology and Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
| | - Yuzhang Wu
- Institute of Immunology, The Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038, PR China
| | - Jianxun Song
- Department of Microbiology & Immunology and Penn State Hershey Cancer Institute, The Pennsylvania State University College of Medicine, 500 University Drive, Hershey, PA 17033, USA
- Institute of Immunology, The Third Military Medical University, 30 Gaotanyan Street, Chongqing 400038, PR China
| |
Collapse
|
294
|
Littman DR, Rudensky AY. Th17 and regulatory T cells in mediating and restraining inflammation. Cell 2010; 140:845-58. [PMID: 20303875 DOI: 10.1016/j.cell.2010.02.021] [Citation(s) in RCA: 781] [Impact Index Per Article: 55.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2010] [Revised: 02/11/2010] [Accepted: 02/13/2010] [Indexed: 12/22/2022]
Abstract
The vertebrate immune system is poised in a state of equilibrium that permits accurate and rapid protective responses against pathogens but curtails potential for causing harm to the host through targeting of "self" and provoking overexuberant inflammatory processes. In this Review we discuss this balance achieved in large part by interactions of different classes of T lymphocytes that have potent pro- or anti-inflammatory activity in the context of genetic and environmental factors, particularly the commensal microbiota.
Collapse
Affiliation(s)
- Dan R Littman
- Howard Hughes Medical Institute, The Kimmel Center for Biology and Medicine of the Skirball Institute, New York University School of Medicine, New York, 10016, USA.
| | | |
Collapse
|
295
|
González Parias JL, Duque Giraldo VE, Velásquez-Lopera MM. FOXP3: Controlador maestro de la generación y función de las células reguladoras naturales. ACTA ACUST UNITED AC 2010. [DOI: 10.1016/s0213-9626(10)70013-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
296
|
Vang KB, Yang J, Pagán AJ, Li LX, Wang J, Green JM, Beg AA, Farrar MA. Cutting edge: CD28 and c-Rel-dependent pathways initiate regulatory T cell development. THE JOURNAL OF IMMUNOLOGY 2010; 184:4074-7. [PMID: 20228198 DOI: 10.4049/jimmunol.0903933] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Regulatory T cell (Treg) development proceeds via a two-step process in which naive CD4(+) thymocytes are first converted into CD4(+)CD25(+)CD122(+)GITR(+)Foxp3(-) Treg progenitors, followed by a second step in which IL-2 converts these Treg progenitors into CD4(+)Foxp3(+) Tregs. The costimulatory molecule CD28 is required for efficient Treg development. However, the stage at which CD28 affects Treg development remains undefined. In this article, we demonstrate that Cd28(-/-) mice lack Treg progenitors. Furthermore, the P(187)YAP motif in the cytoplasmic tail of CD28, which links CD28 to Lck activation, is required for this process. In contrast, the Y(170)MNM motif, which links CD28 to PI3K activation, is not required for Treg progenitor development. Finally, the CD28/Lck pathway was shown to activate the NF-kappaB family of transcription factors. We demonstrate that c-Rel, but not NF-kappaB1, promotes the development of Treg progenitors. Thus, a CD28/c-Rel-dependent pathway is involved in initiating Treg development.
Collapse
Affiliation(s)
- Kieng B Vang
- Department of Laboratory Medicine and Pathology, The Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | | | | | | | | | |
Collapse
|
297
|
Abstract
Natural regulatory T cells (nTregs) are defined by their inherent ability to establish and maintain peripheral self-tolerance. In recent years, the development of nTregs has come under close examination with the advent of Forkhead Box P3 protein (FOXP3)-green fluorescent protein reporter mice that pinpointed the initiation of FOXP3 expression within the thymus. The mechanism and pathway of nTreg development has only recently been studied in detail and to a large degree remains unclear. In this review, we will discuss our current understanding of nTreg lineage choice and development from a cellular and intracellular standpoint.
Collapse
Affiliation(s)
- Matthew L Bettini
- Department of Immunology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105-3678, USA
| | | |
Collapse
|
298
|
Bcl-xL is required for the development of functional regulatory CD4 cells in lupus-afflicted mice following treatment with a tolerogenic peptide. J Autoimmun 2010; 34:87-95. [DOI: 10.1016/j.jaut.2009.06.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2009] [Revised: 06/10/2009] [Accepted: 06/14/2009] [Indexed: 02/01/2023]
|
299
|
Ohkura N, Sakaguchi S. Regulatory T cells: roles of T cell receptor for their development and function. Semin Immunopathol 2010; 32:95-106. [PMID: 20179931 DOI: 10.1007/s00281-010-0200-5] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Accepted: 01/28/2010] [Indexed: 12/31/2022]
Abstract
Naturally arising CD4(+)CD25(+) regulatory T cells (Treg cells), which specifically express the forkhead family transcription factor Foxp3, are essential for the maintenance of immunological self-tolerance and immune homeostasis. Stimulation of the T cell antigen receptor (TCR) via recognizing self-peptide/major histocompatibility complex (MHC) is required for their expression of Foxp3 in the course of their development in the thymus. The TCR repertoires displayed by Treg cells and naïve T cells are apparently distinct, suggesting that Treg cells with high reactivity to self-peptide/MHC ligands are somehow driven to Treg cell lineage in the thymus. Treg cells also require stimulation via TCR to exert suppression in the periphery. At the molecular level, assembly of Foxp3, Foxp3-interacting factors, and chromatin-remodeling factors is in part under the control of TCR signaling, and TCR stimulation alters Foxp3-dependent transcriptional regulation, protein-protein interaction, and Foxp3 recruitment to the specific genomic loci. These findings collectively indicate that the TCR signaling is essential for suppressive function of Treg cells and that TCR has a determinant role for driving developing T cells to the Foxp3(+)CD4(+)CD25(+) Treg cell lineage and differentiation.
Collapse
Affiliation(s)
- Naganari Ohkura
- Department of Experimental Pathology, Institute for Frontier Medical Sciences, Kyoto University, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan.
| | | |
Collapse
|
300
|
Hanabuchi S, Ito T, Park WR, Watanabe N, Shaw JL, Roman E, Arima K, Wang YH, Voo KS, Cao W, Liu YJ. Thymic stromal lymphopoietin-activated plasmacytoid dendritic cells induce the generation of FOXP3+ regulatory T cells in human thymus. THE JOURNAL OF IMMUNOLOGY 2010; 184:2999-3007. [PMID: 20173030 DOI: 10.4049/jimmunol.0804106] [Citation(s) in RCA: 146] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Human thymus contains major dendritic cell (DC) subsets, myeloid DCs (mDCs), and plasmacytoid DCs (pDCs). We previously showed that mDCs, educated by thymic stromal lymphopoietin (TSLP) produced by the epithelial cells of the Hassall's corpuscles, induced differentiation of CD4(+)CD25(-) thymocytes into Forkhead Box P3(+) (FOXP3(+)) regulatory T cells (T(R)) within the medulla of human thymus. In this study, we show that pDCs expressed the TSLP receptor and IL-7 receptor alpha complexes upon activation and became responsive to TSLP. TSLP-activated human pDCs secrete macrophage-derived chemokine CCL-22 and thymus- and activation-regulated chemokine CCL-17 but not Th1- or Th2-polarizing cytokines. TSLP-activated pDCs induced the generation of FOXP3(+) T(R) from CD4(+)CD8(-)CD25(-) thymocytes, which could be strongly inhibited by Th1-polarizing cytokine IL-12 or Th2-polarizing cytokine IL-4. Interestingly, the FOXP3(+) T(R) induced by the TSLP-pDCs expressed more IL-10 but less TGF-beta than that induced by the TSLP-mDCs. These data suggest that TSLP expressed by thymic epithelial cells can activate mDCs and pDCs to positively select the FOXP3(+) T(R) with different cytokine production potential in human thymus. The inability of TSLP to induce DC maturation without producing Th1- or Th2-polarizing cytokines may provide a thymic niche for T(R) development.
Collapse
Affiliation(s)
- Shino Hanabuchi
- Department of Immunology and Center for Cancer Immunology Research, University of Texas MD Anderson Cancer Center, Houston, TX 77030-1903, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|