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Regulatory T cell niche in the bone marrow, a new player in Haematopoietic stem cell transplantation. Blood Rev 2022; 59:101030. [PMID: 36336520 DOI: 10.1016/j.blre.2022.101030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 10/03/2022] [Accepted: 10/26/2022] [Indexed: 11/20/2022]
Abstract
Challenges in haematopoietic stem cell transplantation such as low bone marrow (BM) engraftment, graft versus host disease (GvHD) and the need for long-term immunosuppression could be addressed using T regulatory cells (Tregs) resident in the tissue of interest, in this case, BM Tregs. Controlling the adverse immune response in haematopoietic stem cell transplantation (HSCT) and minimising the associated risks such as infection and secondary cancers due to long-term immunosuppression is a crucial aspect of clinical practice in this field. While systemic immunosuppressive therapy could achieve reasonable GvHD control in most patients, related side effects remain the main limiting factor. Developing more targeted immunosuppressive strategies is an unmet clinical need and is the focus of several ongoing research projects. Tregs are a non-redundant sub-population of CD4+ T cells essential for controlling the immune homeostasis. Tregs are known to be reduced in number and function in autoimmune conditions. There is considerable interest in these cells as cell therapy products since they can be expanded in vitro and infused into patients. These trials have found Treg therapy to be safe, well-tolerated, and with some early signs of efficacy. However, Tregs are a heterogeneous subpopulation of T cells, and several novel subpopulations have been identified in recent years beyond the conventional thymic (tTregs) and peripheral (pTregs). There is increasing evidence for the presence of resident and tissue-specific Tregs. Bone marrow (BM) Tregs are one example of tissue-resident Tregs. BM Tregs are enriched within the marrow, serving a dual function of immunosuppression and maintenance of haematopoietic stem cells (HSCs). HSCs maintenance is achieved through direct suppression of HSCs differentiation, maintaining a proliferating pool of HSCs, and promoting the development of functional stromal cells that support HSCs. In this review, we will touch upon the biology of Tregs, focusing on their development and heterogeneity. We will focus on the BM Tregs from their biology to their therapeutic potential, focusing on their use in HSCT.
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2
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Corcos N, Culina S, Deligne C, Lavaud C, You S, Mallone R. Oral Fc-Coupled Preproinsulin Achieves Systemic and Thymic Delivery Through the Neonatal Fc Receptor and Partially Delays Autoimmune Diabetes. Front Immunol 2021; 12:616215. [PMID: 34447366 PMCID: PMC8382691 DOI: 10.3389/fimmu.2021.616215] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Accepted: 07/27/2021] [Indexed: 11/30/2022] Open
Abstract
Tolerogenic vaccinations using beta-cell antigens are attractive for type 1 diabetes prevention, but clinical trials have been disappointing. This is probably due to the late timing of intervention, when multiple auto-antibodies are already present. We therefore devised a strategy to introduce the initiating antigen preproinsulin (PPI) during neonatal life, when autoimmunity is still silent and central tolerance mechanisms, which remain therapeutically unexploited, are more active. This strategy employs an oral administration of PPI-Fc, i.e. PPI fused with an IgG Fc to bind the intestinal neonatal Fc receptor (FcRn) that physiologically delivers maternal antibodies to the offspring during breastfeeding. Neonatal oral PPI-Fc vaccination did not prevent diabetes development in PPI T-cell receptor-transgenic G9C8.NOD mice. However, PPI-Fc was efficiently transferred through the intestinal epithelium in an Fc- and FcRn-dependent manner, was taken up by antigen presenting cells, and reached the spleen and thymus. Although not statistically significant, neonatal oral PPI-Fc vaccination delayed diabetes onset in polyclonal Ins2-/-.NOD mice that spontaneously develop accelerated diabetes. Thus, this strategy shows promise in terms of systemic and thymic antigen delivery via the intestinal FcRn pathway, but the current PPI-Fc formulation/regimen requires further improvements to achieve diabetes prevention.
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Affiliation(s)
- Noémie Corcos
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Slobodan Culina
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Claire Deligne
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Cassandra Lavaud
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Sylvaine You
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France
| | - Roberto Mallone
- Université de Paris, Institut Cochin, CNRS, INSERM, Paris, France.,Assistance Publique Hôpitaux de Paris, Hôpitaux Universitaires de Paris Centre-Université de Paris, Cochin Hospital, Service de Diabétologie et Immunologie Clinique, Paris, France
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3
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Barik S, Ellis JS, Cascio JA, Miller MM, Ukah TK, Cattin-Roy AN, Zaghouani H. IL-4/IL-13 Heteroreceptor Influences Th17 Cell Conversion and Sensitivity to Regulatory T Cell Suppression To Restrain Experimental Allergic Encephalomyelitis. THE JOURNAL OF IMMUNOLOGY 2017; 199:2236-2248. [PMID: 28801358 DOI: 10.4049/jimmunol.1700372] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 07/21/2017] [Indexed: 01/04/2023]
Abstract
IL-4 and IL-13 have been defined as anti-inflammatory cytokines that can counter myelin-reactive T cells and modulate experimental allergic encephalomyelitis. However, it is not known whether endogenous IL-4 and IL-13 contribute to the maintenance of peripheral tolerance and whether their function is coordinated with T regulatory cells (Tregs). In this study, we used mice in which the common cytokine receptor for IL-4 and IL-13, namely the IL-4Rα/IL-13Rα1 (13R) heteroreceptor (HR), is compromised and determined whether the lack of signaling by endogenous IL-4 and IL-13 through the HR influences the function of effector Th1 and Th17 cells in a Treg-dependent fashion. The findings indicate that mice-deficient for the HR (13R-/-) are more susceptible to experimental allergic encephalomyelitis than mice sufficient for the HR (13R+/+) and develop early onset and more severe disease. Moreover, Th17 cells from 13R-/- mice had reduced ability to convert to Th1 cells and displayed reduced sensitivity to suppression by Tregs relative to Th17 effectors from 13R+/+ mice. These observations suggest that IL-4 and IL-13 likely operate through the HR and influence Th17 cells to convert to Th1 cells and to acquire increased sensitivity to suppression, leading to control of immune-mediated CNS inflammation. These previously unrecognized findings shed light on the intricacies underlying the contribution of cytokines to peripheral tolerance and control of autoimmunity.
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Affiliation(s)
- Subhasis Barik
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212
| | - Jason S Ellis
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212
| | - Jason A Cascio
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212
| | - Mindy M Miller
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212
| | - Tobechukwu K Ukah
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212
| | - Alexis N Cattin-Roy
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212
| | - Habib Zaghouani
- Department of Molecular Microbiology and Immunology, University of Missouri School of Medicine, Columbia, MO 65212; .,Department of Child Health, University of Missouri School of Medicine, Columbia, MO 65212; and.,Department of Neurology, University of Missouri School of Medicine, Columbia, MO 65212
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Gupta N, Culina S, Meslier Y, Dimitrov J, Arnoult C, Delignat S, Gangadharan B, Lecerf M, Justesen S, Gouilleux-Gruart V, Salomon BL, Scott DW, Kaveri SV, Mallone R, Lacroix-Desmazes S. Regulation of immune responses to protein therapeutics by transplacental induction of T cell tolerance. Sci Transl Med 2015; 7:275ra21. [PMID: 25696000 DOI: 10.1126/scitranslmed.aaa1957] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Central tolerance plays a key role in modulating immune responses to self and exogenous antigens. The absence of self-antigen expression, as in patients with genetic deficiencies, prevents the development of antigen-specific immune tolerance. Hence, a substantial number of patients develop neutralizing antibodies to the corresponding protein therapeutics after replacement treatment. In this context, the administration of missing antigens during fetal development, a key period for self-tolerance establishment, should confer early and long-lasting antigen-specific tolerance. To this end, we exploited the physiological pathway of the neonatal Fc receptor (FcRn) through which maternal immunoglobulins are transplacentally transferred to fetuses. We demonstrate that Fc-fused antigens administered to pregnant mice reach fetal lymphoid organs in an FcRn-dependent manner, accumulate in antigen-presenting cells of myeloid origin, and promote the generation of both thymic and peripheral antigen-specific regulatory T cells. This strategy was successfully pursued in a mouse model of hemophilia A, where maternofetal transfer of the Fc-fused immunodominant domains of coagulation factor VIII conferred antigen-specific tolerance. Transplacental tolerance induction with Fc-fused proteins may thus prove valuable to prevent alloimmunization after replacement protein therapy for congenital deficiencies.
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Affiliation(s)
- Nimesh Gupta
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France
| | - Slobodan Culina
- INSERM, U1016, Institut Cochin, F-75014 Paris, France. CNRS, UMR8104, F-75014 Paris, France. Université Paris Descartes, Sorbonne Paris Cité, F-75006 Paris, France
| | - Yann Meslier
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France
| | - Jordan Dimitrov
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France
| | - Christophe Arnoult
- Université François-Rabelais de Tours, CNRS, Génétique, Immunothérapie, Chimie et Cancer (GICC), UMR 7292, F-37032 Tours, France
| | - Sandrine Delignat
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France
| | - Bagirath Gangadharan
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France
| | - Maxime Lecerf
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France
| | - Sune Justesen
- Laboratory of Experimental Immunology, Faculty of Health Sciences, University of Copenhagen, 2200 Copenhagen, Denmark
| | - Valérie Gouilleux-Gruart
- Université François-Rabelais de Tours, CNRS, Génétique, Immunothérapie, Chimie et Cancer (GICC), UMR 7292, F-37032 Tours, France. CHRU de Tours, Laboratory of Immunology, F-37044 Tours, France
| | - Benoit L Salomon
- Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France. CNRS, ERL 8255, INSERM U1135, F-75013 Paris, France
| | - David W Scott
- Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Srinivas V Kaveri
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France. Laboratoire International Associé IMPACT (INSERM, France-Indian Council of Medical Research, India), F-75006 Paris, France
| | - Roberto Mallone
- INSERM, U1016, Institut Cochin, F-75014 Paris, France. CNRS, UMR8104, F-75014 Paris, France. Université Paris Descartes, Sorbonne Paris Cité, F-75006 Paris, France. Assistance Publique Hôpitaux de Paris, Service de Diabétologie, Hôpital Cochin, F-75014 Paris, France
| | - Sébastien Lacroix-Desmazes
- INSERM, U1138, F-75006 Paris, France. Centre de Recherche des Cordeliers (CRC), Equipe - Immunopathology and Therapeutic Immunointervention, F-75006 Paris, France. Sorbonne Universités, Université Pierre et Marie Curie (UPMC)-Paris 6, UMR S 1138 and UMR S CR7, F-75006 Paris, France. Laboratoire International Associé IMPACT (INSERM, France-Indian Council of Medical Research, India), F-75006 Paris, France.
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5
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Culina S, Gupta N, Boisgard R, Afonso G, Gagnerault MC, Dimitrov J, Østerbye T, Justesen S, Luce S, Attias M, Kyewski B, Buus S, Wong FS, Lacroix-Desmazes S, Mallone R. Materno-Fetal Transfer of Preproinsulin Through the Neonatal Fc Receptor Prevents Autoimmune Diabetes. Diabetes 2015; 64:3532-42. [PMID: 25918233 DOI: 10.2337/db15-0024] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Accepted: 04/15/2015] [Indexed: 11/13/2022]
Abstract
The first signs of autoimmune activation leading to β-cell destruction in type 1 diabetes (T1D) appear during the first months of life. Thus, the perinatal period offers a suitable time window for disease prevention. Moreover, thymic selection of autoreactive T cells is most active during this period, providing a therapeutic opportunity not exploited to date. We therefore devised a strategy by which the T1D-triggering antigen preproinsulin fused with the immunoglobulin (Ig)G Fc fragment (PPI-Fc) is delivered to fetuses through the neonatal Fc receptor (FcRn) pathway, which physiologically transfers maternal IgGs through the placenta. PPI-Fc administered to pregnant PPIB15-23 T-cell receptor-transgenic mice efficiently accumulated in fetuses through the placental FcRn and protected them from subsequent diabetes development. Protection relied on ferrying of PPI-Fc to the thymus by migratory dendritic cells and resulted in a rise in thymic-derived CD4(+) regulatory T cells expressing transforming growth factor-β and in increased effector CD8(+) T cells displaying impaired cytotoxicity. Moreover, polyclonal splenocytes from nonobese diabetic (NOD) mice transplacentally treated with PPI-Fc were less diabetogenic upon transfer into NOD.scid recipients. Transplacental antigen vaccination provides a novel strategy for early T1D prevention and, further, is applicable to other immune-mediated conditions.
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Affiliation(s)
- Slobodan Culina
- INSERM, U1016, Cochin Institute, Paris, France CNRS, UMR 8104, Cochin Institute, Paris, France Paris Descartes University, Sorbonne Paris Cité, Paris, France
| | - Nimesh Gupta
- INSERM, UMRS 1138, Les Cordeliers Research Center, Paris, France Pierre et Marie Curie-Paris 6 University, Sorbonne Universities, UMRS 1138, Paris, France Paris Descartes University, UMRS 1138, Paris, France
| | - Raphael Boisgard
- CEA/DSV/IBM/SHFJ/U1023, Laboratory of Experimental Molecular Imaging, Orsay, France
| | - Georgia Afonso
- INSERM, U1016, Cochin Institute, Paris, France CNRS, UMR 8104, Cochin Institute, Paris, France Paris Descartes University, Sorbonne Paris Cité, Paris, France
| | - Marie-Claude Gagnerault
- INSERM, U1016, Cochin Institute, Paris, France CNRS, UMR 8104, Cochin Institute, Paris, France Paris Descartes University, Sorbonne Paris Cité, Paris, France
| | - Jordan Dimitrov
- INSERM, UMRS 1138, Les Cordeliers Research Center, Paris, France Pierre et Marie Curie-Paris 6 University, Sorbonne Universities, UMRS 1138, Paris, France Paris Descartes University, UMRS 1138, Paris, France
| | - Thomas Østerbye
- Department of International Health, Immunology and Microbiology, Panum Institute, Copenhagen, Denmark
| | - Sune Justesen
- Department of International Health, Immunology and Microbiology, Panum Institute, Copenhagen, Denmark
| | - Sandrine Luce
- INSERM, U1016, Cochin Institute, Paris, France CNRS, UMR 8104, Cochin Institute, Paris, France Paris Descartes University, Sorbonne Paris Cité, Paris, France
| | - Mikhaël Attias
- INSERM, U1016, Cochin Institute, Paris, France CNRS, UMR 8104, Cochin Institute, Paris, France Paris Descartes University, Sorbonne Paris Cité, Paris, France
| | - Bruno Kyewski
- Division of Developmental Immunology, DKFZ, Heidelberg, Germany
| | - Søren Buus
- Department of International Health, Immunology and Microbiology, Panum Institute, Copenhagen, Denmark
| | - F Susan Wong
- Institute of Molecular & Experimental Medicine, Cardiff University, Cardiff, U.K
| | - Sebastien Lacroix-Desmazes
- INSERM, UMRS 1138, Les Cordeliers Research Center, Paris, France Pierre et Marie Curie-Paris 6 University, Sorbonne Universities, UMRS 1138, Paris, France Paris Descartes University, UMRS 1138, Paris, France
| | - Roberto Mallone
- INSERM, U1016, Cochin Institute, Paris, France CNRS, UMR 8104, Cochin Institute, Paris, France Paris Descartes University, Sorbonne Paris Cité, Paris, France Department of Diabetology, Cochin Hospital, Assistance Publique-Hôpitaux de Paris, Paris, France
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6
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T cell avidity and tumor immunity: problems and solutions. CANCER MICROENVIRONMENT 2013; 7:1-9. [PMID: 24357332 DOI: 10.1007/s12307-013-0143-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 12/05/2013] [Indexed: 12/16/2022]
Abstract
A potent T cell response is an important component of durable anti-tumor immunity. The quality of the T cell response can, in-part, be measured by the avidity of the T cell for its tumor antigen-expressing target. While convention suggests that raising the avidity of the responding T cells may make for a more potent anti-tumor immune response, the threshold for effective tumor immunity remains unclear, as do some of the adverse effects of an inappropriately high avidity response. In this review, we discuss the relationship between T cell avidity and anti-tumor immunity, considering both experimental model systems as well as human clinical trials.
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Amedei A, Niccolai E, Benagiano M, Della Bella C, Cianchi F, Bechi P, Taddei A, Bencini L, Farsi M, Cappello P, Prisco D, Novelli F, D'Elios MM. Ex vivo analysis of pancreatic cancer-infiltrating T lymphocytes reveals that ENO-specific Tregs accumulate in tumor tissue and inhibit Th1/Th17 effector cell functions. Cancer Immunol Immunother 2013; 62:1249-60. [PMID: 23640603 PMCID: PMC11028529 DOI: 10.1007/s00262-013-1429-3] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 04/24/2013] [Indexed: 02/06/2023]
Abstract
Pancreatic cancer (PC) is an aggressive disease with dismal prognosis. Surgical resection is the recommended treatment for long-term survival, but patients with resectable PC are in the minority (with a 5-year survival rate of 20 %). Therefore, development of novel therapeutic strategies, such as anti-PC immunotherapy, is crucial. α-Enolase (ENO1) is an enzyme expressed on the surface of pancreatic cancer cells and is able to promote cell migration and cancer metastasis. The capacity of ENO1 to induce an immune response in PC patients renders it a true tumor-associated antigen. In this study, we characterized the effector functions of ENO1-specific T cells isolated from PC patients, and we specifically evaluated the successful role of intra-tumoral T helper 17 (Th17) cells and the inhibitory role of regulatory T (Tregs) cells in respectively promoting or reducing the cancer-specific immune response. In this ex vivo study, we have demonstrated, for the first time, that ENO1-specific Th17 cells have a specific anti-cancer effector function in PC patients, and that there are decreased levels of these cells in cancer compared to healthy mucosa. Conversely, there are elevated levels of ENO1-specific Tregs in PC patients which lead to inhibition of the antigen-specific effector T cells, thus highlighting a possible role in promoting PC progression. These results may be relevant for the design of novel immunotherapeutic strategies in pancreatic cancer.
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Affiliation(s)
- Amedeo Amedei
- Division of Internal Medicine, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134, Florence, Italy.
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8
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Lynch JN, Donermeyer DL, Weber KS, Kranz DM, Allen PM. Subtle changes in TCRα CDR1 profoundly increase the sensitivity of CD4 T cells. Mol Immunol 2012; 53:283-94. [PMID: 22982754 DOI: 10.1016/j.molimm.2012.08.020] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2012] [Revised: 08/15/2012] [Accepted: 08/18/2012] [Indexed: 10/27/2022]
Abstract
Changes in the peptide and MHC molecules have been extensively examined for how they alter T cell activation, but many fewer studies have examined the TCR. Structural studies of how TCR differences alter T cell specificity have focused on broad variation in the CDR3 loops. However, changes in the CDR1 and 2 loops can also alter TCR recognition of pMHC. In this study we focus on two mutations in the CDR1α loop of the TCR that increased the affinity of a TCR for agonist Hb(64-76)/I-E(k) by increasing the on-rate of the reaction. These same mutations also conferred broader recognition of altered peptide ligands. TCR transgenic mice expressing the CDR1α mutations had altered thymic selection, as most of the T cells were negatively selected compared to T cells expressing the wildtype TCR. The few T cells that escaped negative selection and were found in the periphery were rendered anergic, thereby avoiding autoimmunity. T cells with the CDR1α mutations were completely deleted in the presence of Hb(64-76) as an endogenous peptide. Interestingly, the wildtype T cells were not eliminated, identifying a threshold affinity for negative selection where a 3-fold increase in affinity is the difference between incomplete and complete deletion. Overall, these studies highlight how small changes in the TCR can increase the affinity of TCR:pMHC but with the consequences of skewing selection and producing an unresponsive T cell.
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Affiliation(s)
- Jennifer N Lynch
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110, United States
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9
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Ruan Q, Chen YH. Nuclear factor-κB in immunity and inflammation: the Treg and Th17 connection. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2012; 946:207-21. [PMID: 21948370 DOI: 10.1007/978-1-4614-0106-3_12] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Although nuclear factor-kB (NF-kB) is generally considered to be a pro-inflammatory transcription factor, recent studies indicate that it also plays a critical role in the development of an anti-inflammatory T cell subset called regulatory T (Treg) cells. Two NF-kB proteins, c-Rel and p65, drive the development of Treg cells by promoting the formation of a Foxp3-specific enhanceosome. Consequently, c-Rel-deficient mice have marked reductions in Treg cells, and c-Rel-deficient T cells are compromised in Treg cell differentiation. However, with the exception of Foxp3, most NF-kB target genes in immune cells are pro-inflammatory. These include several Th17-related cytokine genes and the retinoid-related orphan receptor-g (Rorg or Rorc) that specifies Th17 differentiation and lineage-specific function. T cells deficient in c-Rel or p65 are significantly compromised in Th17 differentiation, and c-Rel -deficient mice are defective in Th17 responses. Thus, NF-kB is required for the development of both anti-inflammatory Treg and pro-inflammatory Th17 cells.
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Affiliation(s)
- Qingguo Ruan
- Department of Pathology and Laboratory Medicine, 712 Stellar-Chance Laboratories, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
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10
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Valentino MD, Abdul-Alim CS, Maben ZJ, Skrombolas D, Hensley LL, Kawula TH, Dziejman M, Lord EM, Frelinger JA, Frelinger JG. A broadly applicable approach to T cell epitope identification: application to improving tumor associated epitopes and identifying epitopes in complex pathogens. J Immunol Methods 2011; 373:111-26. [PMID: 21872603 DOI: 10.1016/j.jim.2011.08.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Revised: 08/10/2011] [Accepted: 08/11/2011] [Indexed: 12/22/2022]
Abstract
Epitopes are a hallmark of the antigen specific immune response. The identification and characterization of epitopes is essential for modern immunologic studies, from investigating cellular responses against tumors to understanding host/pathogen interactions especially in the case of bacteria with intracellular residence. Here, we have utilized a novel approach to identify T cell epitopes exploiting the exquisite ability of particulate antigens, in the form of beads, to deliver exogenous antigen to both MHC class I and class II pathways for presentation to T cell hybridomas. In the current study, we coupled this functional assay with two distinct protein expression libraries to develop a methodology for the characterization of T cell epitopes. One set of expression libraries containing single amino acid substitutions in a defined epitope sequence was interrogated to identify epitopes with enhanced T cell stimulation for a MHC class I epitope. The second expression library is comprised of the majority of open reading frames from the intracellular pathogen and potential biowarfare agent, Francisella tularensis. By automating aspects of this technology, we have been able to functionally screen and identify novel T cell epitopes within F. tularensis. We have also expanded upon these studies to generate a novel expression vector that enables immunization of recombinant protein into mice, which has been utilized to facilitate T cell epitope discovery for proteins that are critically linked to Francisella pathogenicity. This methodology should be applicable to a variety of systems and other pathogens.
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Affiliation(s)
- Michael D Valentino
- Department of Microbiology and Immunology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
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11
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Abstract
Recent research on T cell-antigen interactions suggests that tighter binding is not always better at eliciting an effective immune response.
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12
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Bibliography. Current world literature. Curr Opin Endocrinol Diabetes Obes 2009; 16:328-37. [PMID: 19564733 DOI: 10.1097/med.0b013e32832eb365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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13
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Shanley DP, Aw D, Manley NR, Palmer DB. An evolutionary perspective on the mechanisms of immunosenescence. Trends Immunol 2009; 30:374-81. [PMID: 19541538 DOI: 10.1016/j.it.2009.05.001] [Citation(s) in RCA: 189] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2009] [Revised: 04/12/2009] [Accepted: 05/11/2009] [Indexed: 10/20/2022]
Abstract
There is an accumulating body of evidence that a decline in immune function with age is common to most if not all vertebrates. For instance, age-associated thymic involution seems to occur in all species that possess a thymus, indicating that this process is evolutionary ancient and conserved. The precise mechanisms regulating immunosenescence remain to be resolved, but much of what we do know is consistent with modern evolutionary theory. In this review, we assess our current knowledge from an evolutionary perspective on the occurrence of immunosenescence, we show that life history trade-offs play a key role and we highlight the possible advantages of the age-related decline in thymic function.
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Affiliation(s)
- Daryl P Shanley
- Institute for Ageing and Health, Newcastle University, Newcastle upon Tyne NE4 5PL, UK
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Shen S, Zhu M, Lau J, Chuck M, Zhang W. The essential role of LAT in thymocyte development during transition from the double-positive to single-positive stage. THE JOURNAL OF IMMUNOLOGY 2009; 182:5596-604. [PMID: 19380807 DOI: 10.4049/jimmunol.0803170] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The linker for activation of T cells (LAT) is an adaptor protein that couples TCR engagement to downstream signaling cascades. LAT is important in early thymocyte development as LAT-deficient mice have a complete block at the double-negative (DN) 3 stage. To study the role of LAT beyond the DN3 stage, we generated mice in which the lat gene could be deleted by the Cre recombinase. Analysis of these mice showed that deletion of LAT after the DN3 stage allowed thymocytes to develop past the DN3 to DN4 checkpoint and to generate double-positive thymocytes. However, LAT-deficient DP thymocytes were severely defective in responding to stimulation via the TCR and failed to differentiate into single-positive thymocytes efficiently. Consequently, few LAT-deficient mature T cells could be found in the periphery. These T cells had undergone extensive homeostatic proliferation and expressed low levels of the TCR on their surface. Collectively, our data indicate that in addition to its role in pre-TCR signaling, LAT also plays an essential role in thymocyte development during transition from the double-positive to single-positive stage.
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Affiliation(s)
- Shudan Shen
- Department of Immunology, Duke University Medical Center, Durham, NC 27710, USA
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15
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