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McLachlan SM, Aliesky HA, Rapoport B. A Mouse Thyrotropin Receptor A-Subunit Transgene Expressed in Thyroiditis-Prone Mice May Provide Insight into Why Graves' Disease Only Occurs in Humans. Thyroid 2019; 29:1138-1146. [PMID: 31184281 PMCID: PMC6707033 DOI: 10.1089/thy.2019.0260] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Background: Graves' disease, caused by autoantibodies that activate the thyrotropin (TSH) receptor (TSHR), has only been reported in humans. Thyroiditis-prone NOD.H2h4 mice develop autoantibodies to thyroglobulin (Tg) and thyroid peroxidase (TPO) but not to the TSHR. Evidence supports the importance of the shed TSHR A-subunit in the initiation and/or amplification of the autoimmune response to the holoreceptor. Cells expressing the gene for the isolated A-subunit secrete A-subunit protein, a surrogate for holoreceptor A-subunit shedding. NOD.H2h4 mice with the human TSHR A-subunit targeted to the thyroid (a "self" antigen in such transgenic (Tgic) animals), unlike their wild-type (wt) siblings, spontaneously develop pathogenic TSHR antibodies to the human-TSH holoreceptor. These autoantibodies do not recognize the endogenous mouse-TSH holoreceptor and do not cause hyperthyroidism. Methods: We have now generated NOD.H2h4 mice with the mouse-TSHR A-subunit transgene targeted to the thyroid. Tgic mice and wt littermates were compared for intrathyroidal expression of the mouse A-subunit. Sera from six-month-old mice were tested for the presence of autoantibodies to Tg and TPO as well as for pathogenic TSHR antibodies (TSH binding inhibition, bioassay for thyroid stimulating antibodies) and nonpathogenic TSHR antibodies (ELISA). Results: Expression of the mouse TSHR A-subunit transgene in the thyroid was confirmed by real-time polymerase chain reaction in the Tgics and had no effect on the spontaneous development of autoantibodies to Tg or TPO. However, unlike the same NOD.H2h4 strain with the human-TSHR A-subunit target to the thyroid, mice expressing intrathyroidal mouse-TSHR A subunit failed to develop either pathogenic or nonpathogenic TSHR antibodies. The mouse TSHR A-subunit differs from the human TSHR A-subunit in terms of its amino acid sequence and has one less glycosylation site than the human TSHR A-subunit. Conclusions: Multiple genetic and environmental factors contribute to the pathogenesis of Graves' disease. The present study suggests that the TSHR A-subunit structure (possibly including posttranslational modification such as glycosylation) may explain, in part, why Graves' disease only develops in humans.
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Affiliation(s)
- Sandra M. McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, Los Angeles, California
- UCLA School of Medicine, University of California, Los Angeles, California
- Address correspondence to: Sandra M. McLachlan, PhD, Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, 8700 Beverly Boulevard, B-131, Los Angeles, CA 90048
| | - Holly A. Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, Los Angeles, California
| | - Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, Los Angeles, California
- UCLA School of Medicine, University of California, Los Angeles, California
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2
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McLachlan SM, Aliesky HA, Rapoport B. Nanoparticles Bearing TSH Receptor Protein and a Tolerogenic Molecule Do Not Induce Immune Tolerance but Exacerbate Thyroid Autoimmunity in hTSHR/NOD. H2h4 Mice. THE JOURNAL OF IMMUNOLOGY 2019; 202:2570-2577. [PMID: 30944161 DOI: 10.4049/jimmunol.1900038] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 03/03/2019] [Indexed: 02/06/2023]
Abstract
Transgenic NOD.H2h4 mice that express the human (h) TSHR A-subunit in the thyroid gland spontaneously develop pathogenic TSHR autoantibodies resembling those in patients with Graves disease. Nanoparticles coupled to recombinant hTSHR A-subunit protein and a tolerogenic molecule (ligand for the endogenous aryl-hydrocarbon receptor; ITE) were injected i.p. four times at weekly intervals into hTSHR/NOD.H2h4 mice with the goal of blocking TSHR Ab development. Unexpectedly, in transgenic mice, injecting TSHR A-subunit-ITE nanoparticles (not ITE-nanoparticles or buffer) accelerated and enhanced the development of pathogenic TSHR Abs measured by inhibition of TSH binding to the TSHR. Nonpathogenic TSHR Abs (ELISA) were enhanced in transgenics and induced in wild-type littermates. Serendipitously, these findings have important implications for disease pathogenesis: development of Graves TSHR Abs is limited by the availability of A-subunit protein, which is shed from membrane bound TSHR, expressed at low levels in the thyroid. The enhanced TSHR Ab response following injected TSHR A-subunit protein-nanoparticles is reminiscent of the transient increase in pathogenic TSHR Abs following the release of thyroid autoantigens after radio-iodine therapy in Graves patients. However, in the hTSHR/NOD.H2h4 model, enhancement is specific for TSHR Abs, with Abs to thyroglobulin and thyroid peroxidase remaining unchanged. In conclusion, despite the inclusion of a tolerogenic molecule, injected nanoparticles coated with TSHR A-subunit protein enhanced and accelerated development of pathogenic TSHR Abs in hTSHR/NOD. NOD.H2h4 These findings emphasize the need for sufficient TSHR A-subunit protein to activate the immune system and the generation of stimulatory TSHR Abs in genetically predisposed individuals.
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Affiliation(s)
- Sandra M McLachlan
- Cedars-Sinai Medical Center, Los Angeles, CA 90048; and .,David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
| | | | - Basil Rapoport
- Cedars-Sinai Medical Center, Los Angeles, CA 90048; and.,David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095
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3
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McLachlan SM, Aliesky HA, Rapoport B. To reflect human autoimmune thyroiditis, thyroid peroxidase (not thyroglobulin) antibodies should be measured in female (not sex-independent) NOD.H2 h4 mice. Clin Exp Immunol 2019; 196:52-58. [PMID: 30566234 DOI: 10.1111/cei.13249] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/03/2018] [Indexed: 12/23/2022] Open
Abstract
NOD.H2h4 mice are the most commonly used model for human autoimmune thyroiditis. Because thyroid autoimmunity develops slowly (over months), NOD.H2h4 mice are usually exposed to excess dietary iodide to accelerate and amplify the process. However, unlike the female bias in human thyroid autoimmunity, autoantibodies to thyroglobulin (TgAb) are reported to be similar in male and female NOD.H2h4 . We sought evidence for sexual dimorphism in other parameters in this strain maintained on regular or iodized water. Without iodide, TgAb levels are higher in males than in females, the reverse of human disease. In humans, autoantibodies to thyroid peroxidase (TPOAb) are a better marker of disease than TgAb. In NOD.H2h4 mice TPOAb develop more slowly than TgAb, being detectable at 6 months of age versus 4 months for the latter. Remarkably, unlike TgAb, TPOAb levels are higher in female than male NOD.H2h4 mice on both regular and iodized water. As previously observed, serum T4 levels are similar in both sexes. However, thyroid-stimulating hormone (TSH) levels are significantly higher in males than females with or without iodide exposure. TSH levels correlate with TgAb levels in male NOD.H2h4 mice, suggesting a possible role for TSH in TgAb development. However, there is no correlation between TSH and TPOAb levels, the latter more important than TgAb in human disease. In conclusion, if the goal of an animal model is to closely reflect human disease, TPOAb rather than TgAb should be measured in older female NOD.H2h4 mice, an approach requiring patience and the use of mouse TPO protein.
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Affiliation(s)
- S M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, Los Angeles, CA, USA
| | - H A Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, Los Angeles, CA, USA
| | - B Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, Los Angeles, CA, USA
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4
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Schlüter A, Horstmann M, Diaz-Cano S, Plöhn S, Stähr K, Mattheis S, Oeverhaus M, Lang S, Flögel U, Berchner-Pfannschmidt U, Eckstein A, Banga JP. Genetic immunization with mouse thyrotrophin hormone receptor plasmid breaks self-tolerance for a murine model of autoimmune thyroid disease and Graves' orbitopathy. Clin Exp Immunol 2017; 191:255-267. [PMID: 29058307 DOI: 10.1111/cei.13075] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/20/2017] [Indexed: 01/08/2023] Open
Abstract
Experimental models of Graves' hyperthyroid disease accompanied by Graves' orbitopathy (GO) can be induced efficiently in susceptible inbred strains of mice by immunization by electroporation of heterologous human TSH receptor (TSHR) A-subunit plasmid. In this study, we report on the development of a bona fide murine model of autoimmune Graves' disease induced with homologous mouse TSHR A-subunit plasmid. Autoimmune thyroid disease in the self-antigen model was accompanied by GO and characterized by histopathology of hyperplastic glands with large thyroid follicular cells. Examination of orbital tissues showed significant inflammation in extra-ocular muscle with accumulation of T cells and macrophages together with substantial deposition of adipose tissue. Notably, increased levels of brown adipose tissue were present in the orbital tissue of animals undergoing experimental GO. Further analysis of inflammatory loci by 19 F-magnetic resonance imaging showed inflammation to be confined to orbital muscle and optic nerve, but orbital fat showed no difference in inflammatory signs in comparison to control β-Gal-immunized animals. Pathogenic antibodies induced to mouse TSHR were specific for the self-antigen, with minimal cross-reactivity to human TSHR. Moreover, compared to other self-antigen models of murine Graves' disease induced in TSHR knock-out mice, the repertoire of autoantibodies to mouse TSHR generated following the breakdown of thymic self-tolerance is different to those that arise when tolerance is not breached immunologically, as in the knock-out models. Overall, we show that mouse TSHR A-subunit plasmid immunization by electroporation overcomes tolerance to self-antigen to provide a faithful model of Graves' disease and GO.
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Affiliation(s)
- A Schlüter
- Molecular Ophthalmology, Departments of Ophthalmology University Hospital Essen, Germany.,Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Essen, Essen, Germany
| | - M Horstmann
- Molecular Ophthalmology, Departments of Ophthalmology University Hospital Essen, Germany
| | - S Diaz-Cano
- Department of Histopathology, King's College Hospital NHS, London, UK
| | - S Plöhn
- Molecular Ophthalmology, Departments of Ophthalmology University Hospital Essen, Germany
| | - K Stähr
- Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Essen, Essen, Germany
| | - S Mattheis
- Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Essen, Essen, Germany
| | - M Oeverhaus
- Department of Ophthalmology, University Hospital Essen, Essen, Germany
| | - S Lang
- Oto-Rhino-Laryngology, Head and Neck Surgery, University Hospital Essen, Essen, Germany
| | - U Flögel
- Experimental Cardiovascular Imaging, Department of Molecular Cardiology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
| | | | - A Eckstein
- Molecular Ophthalmology, Departments of Ophthalmology University Hospital Essen, Germany.,Department of Ophthalmology, University Hospital Essen, Essen, Germany
| | - J P Banga
- Molecular Ophthalmology, Departments of Ophthalmology University Hospital Essen, Germany
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McLachlan SM, Aliesky H, Banuelos B, Hee SSQ, Rapoport B. Variable Effects of Dietary Selenium in Mice That Spontaneously Develop a Spectrum of Thyroid Autoantibodies. Endocrinology 2017; 158:3754-3764. [PMID: 28938453 PMCID: PMC5695827 DOI: 10.1210/en.2017-00275] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Accepted: 08/18/2017] [Indexed: 12/16/2022]
Abstract
Selenium (Se) is a critical element in thyroid function, and variable dietary Se intake influences immunity. Consequently, dietary Se could influence development of thyroid autoimmunity and provide an adjunct to treat autoimmune thyroid dysfunction. Nonobese diabetic (NOD).H2h4 mice spontaneously develop autoantibodies to thyroglobulin (Tg) and thyroid peroxidase (TPO). This mouse strain expressing a human thyroid-stimulating hormone receptor (TSHR) A-subunit transgene in the thyroid also develops pathogenic TSHR autoantibodies. In this report, we investigated whether dietary Se influences these immune processes. Male and female wild-type and transgenic NOD.H2h4 mice were maintained on normal-, low-, or high-Se (0.1, 0, or 1.0 mg/kg) rodent diets. After 4 months, Se serum levels were extremely low or significantly increased on 0 or 1.0 mg/kg Se, respectively. Varying Se intake affected Tg antibody (TgAb) levels after 2 (but not 4) months; conversely, TPO antibody (TPOAb) levels were altered by dietary Se after 4 (but not 2) months. These data correspond to the earlier development of TgAb than TPOAb in NOD.H2h4 mice. In males, TgAb levels were enhanced by high Se and in females by low Se intake. Se intake had no effect on pathogenic TSHR autoantibodies in TSHR transgenic NOD.H2h4 females. In conclusion, in susceptible NOD.H2h4 mice, we found no evidence that a higher dietary Se intake ameliorates thyroid autoimmunity by reducing autoantibodies to Tg, TPO, or the TSHR. Instead, our finding that low dietary Se potentiates the development of autoantibodies to Tg and TPO in females is consistent with reports in humans of an increased prevalence of autoimmune thyroiditis in low-Se regions.
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Affiliation(s)
- Sandra M. McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, and University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
| | - Holly Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, and University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
| | - Bianca Banuelos
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, and University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
| | - Shane S. Que Hee
- Department of Environmental Health Sciences and Center for Occupational and Environmental Health, Fielding School of Public Health, University of California, Los Angeles, Los Angeles, California 90095
| | - Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, and University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
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6
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McLachlan SM, Lesage S, Collin R, Banuelos B, Aliesky HA, Rapoport B. Genes Outside the Major Histocompatibility Complex Locus Are Linked to the Development of Thyroid Autoantibodies and Thyroiditis in NOD.H2h4 Mice. Endocrinology 2017; 158:702-713. [PMID: 28323998 PMCID: PMC5460802 DOI: 10.1210/en.2016-1875] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Accepted: 01/11/2017] [Indexed: 12/13/2022]
Abstract
Thyroiditis and autoantibodies to thyroglobulin (TgAb) and thyroid peroxidase (TPOAb) develop spontaneously in NOD.H2h4 mice, a phenotype enhanced by dietary iodine. NOD.H2h4 mice were derived by introducing the major histocompatibility class (MHC) molecule I-Ak from B10.A(4R) mice to nonobese diabetic (NOD) mice. Apart from I-Ak, the genes responsible for the NOD.H2h4 phenotype are unknown. Extending serendipitous observations from crossing BALB/c to NOD.H2h4 mice, thyroid autoimmunity was investigated in both genders of the F1, F2, and the second-generation backcross of F1 to NOD.H2h4 (N2). Medium-density linkage analysis was performed on thyroid autoimmunity traits in F2 and N2 progeny. TgAb develop before TPOAb and were measured after 8 and 16 weeks of iodide exposure; TPOAb and thyroiditis were studied at 16 weeks. TgAb, TPOAb, and thyroiditis, absent in BALB/c and F1 mice, developed in most NOD.H2h4 and in more N2 than F2 progeny. No linkages were observed in F2 progeny, probably because of the small number of autoantibody-positive mice. In N2 progeny (equal numbers of males and females), a chromosome 17 locus is linked to thyroiditis and TgAb and is suggestively linked to TPOAb. This locus includes MHC region genes from B10.A(4R) mice (such as I-Ak and Tnf, the latter involved in thyrocyte apoptosis) and genes from NOD mice such as Satb1, which most likely plays a role in immune tolerance. In conclusion, MHC and non-MHC genes, encoded within the chromosome 17 locus from both B10.A(4R) and NOD strains, are most likely responsible for the Hashimoto disease-like phenotype of NOD.H2h4 mice.
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Affiliation(s)
- Sandra M. McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, Los Angeles, California 90048
- University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
| | - Sylvie Lesage
- Department of Immunology-Oncology, Maisonneuve-Rosemont Hospital, Montréal, Québec H1T 2M4, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Roxanne Collin
- Department of Immunology-Oncology, Maisonneuve-Rosemont Hospital, Montréal, Québec H1T 2M4, Canada
- Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, Québec H3C 3J7, Canada
| | - Bianca Banuelos
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, Los Angeles, California 90048
- University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
| | - Holly A. Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, Los Angeles, California 90048
- University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
| | - Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center, Los Angeles, California 90048
- University of California, Los Angeles, School of Medicine, Los Angeles, California 90095
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7
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Ungerer M, Faßbender J, Li Z, Münch G, Holthoff HP. Review of Mouse Models of Graves' Disease and Orbitopathy-Novel Treatment by Induction of Tolerance. Clin Rev Allergy Immunol 2017; 52:182-193. [PMID: 27368808 PMCID: PMC5346423 DOI: 10.1007/s12016-016-8562-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Various approaches have been used to model human Graves' disease in mice, including transfected fibroblasts, and plasmid or adenoviral immunisations with the extracellular A subunit of the human thyrotropin receptor (TSHR). Some of these models were only observed for a short time period or were self-limiting. A long-term model for human Graves' disease was established in mice using continuing immunisations (4-weekly injections) with recombinant adenovirus expressing TSHR. Generation of TSHR binding cAMP-stimulatory antibodies, thyroid enlargement and alterations, elevated serum thyroxin levels, tachycardia and cardiac hypertrophy were maintained for at least 9 months in all Ad-TSHR-immunised mice. Here, we show that these mice suffer from orbitopathy, which was detected by serial orbital sectioning and histomorphometry. Attempts to treat established Graves' disease in preclinical mouse model studies have included small molecule allosteric antagonists and specific antagonist antibodies which were isolated from hypothyroid patients. In addition, novel peptides have been conceived which mimic the cylindrical loops of the TSHR leucine-rich repeat domain, in order to re-establish tolerance toward the antigen. Here, we show preliminary results that one set of these peptides improves or even cures all signs and symptoms of Graves' disease in mice after six consecutive monthly injections. First beneficial effects were observed 3-4 months after starting these therapies. In immunologically naïve mice, administration of the peptides did not induce any immune response.
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Affiliation(s)
- Martin Ungerer
- Procorde (Advancecor), Fraunhoferstrasse 9a, 82152, Martinsried, Germany.
| | - Julia Faßbender
- Procorde (Advancecor), Fraunhoferstrasse 9a, 82152, Martinsried, Germany
| | - Zhongmin Li
- Procorde (Advancecor), Fraunhoferstrasse 9a, 82152, Martinsried, Germany
| | - Götz Münch
- Procorde (Advancecor), Fraunhoferstrasse 9a, 82152, Martinsried, Germany
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McLachlan SM, Aliesky HA, Banuelos B, Lesage S, Collin R, Rapoport B. High-level intrathymic thyrotrophin receptor expression in thyroiditis-prone mice protects against the spontaneous generation of pathogenic thyrotrophin receptor autoantibodies. Clin Exp Immunol 2017; 188:243-253. [PMID: 28099999 PMCID: PMC5383439 DOI: 10.1111/cei.12928] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/03/2017] [Accepted: 01/12/2017] [Indexed: 12/11/2022] Open
Abstract
The thyrotrophin receptor (TSHR) A-subunit is the autoantigen targeted by pathogenic autoantibodies that cause Graves' hyperthyroidism, a common autoimmune disease in humans. Previously, we reported that pathogenic TSHR antibodies develop spontaneously in thyroiditis-susceptible non-obese diabetic (NOD).H2h4 mice bearing a human TSHR A-subunit transgene, which is expressed at low levels in both the thyroid and thymus (Lo-expressor transgene). The present study tested recent evidence that high intrathymic TSHR expression protects against the development of pathogenic TSHR antibodies in humans. By successive back-crossing, we transferred to the NOD.H2h4 background a human TSHR A-subunit transgene expressed at high levels in the thyroid and thymus (Hi-expressor transgene). In the sixth back-cross generation (> 98% NOD.H2h4 genome), only transgenic offspring produced spontaneously immunoglobulin (Ig)G class non-pathogenic human TSHR A-subunit antibodies. In contrast, both transgenic and non-transgenic offspring developed antibodies to thyroglobulin and thyroid peroxidase. However, non-pathogenic human TSHR antibody levels in Hi-expressor offspring were lower than in Lo-expressor transgenic mice. Moreover, pathogenic TSHR antibodies, detected by inhibition of TSH binding to the TSHR, only developed in back-cross offspring bearing the Lo-expressor, but not the Hi-expressor, transgene. High versus low expression human TSHR A-subunit in the NOD.H2h4 thymus was not explained by the transgene locations, namely chromosome 2 (127-147 Mb; Hi-expressor) and chromosome 1 (22.9-39.3 Mb; low expressor). Nevertheless, using thyroiditis-prone NOD.H2h4 mice and two transgenic lines, our data support the association from human studies that low intrathymic TSHR expression is associated with susceptibility to developing pathogenic TSHR antibodies, while high intrathymic TSHR expression is protective.
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Affiliation(s)
- S M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, University of California, Los Angeles, CA, USA
| | - H A Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, University of California, Los Angeles, CA, USA
| | - B Banuelos
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, University of California, Los Angeles, CA, USA
| | - S Lesage
- Department of Immunology-Oncology, Maisonneuve-Rosemont Hospital, Montréal, Québec, Canada and Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, Québec, Canada
| | - R Collin
- Department of Immunology-Oncology, Maisonneuve-Rosemont Hospital, Montréal, Québec, Canada and Département de Microbiologie, Infectiologie et Immunologie, Université de Montréal, Montréal, Québec, Canada
| | - B Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute and UCLA School of Medicine, University of California, Los Angeles, CA, USA
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Rapoport B, Banuelos B, Aliesky HA, Hartwig Trier N, McLachlan SM. Critical Differences between Induced and Spontaneous Mouse Models of Graves' Disease with Implications for Antigen-Specific Immunotherapy in Humans. THE JOURNAL OF IMMUNOLOGY 2016; 197:4560-4568. [PMID: 27913646 DOI: 10.4049/jimmunol.1601393] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 10/14/2016] [Indexed: 01/20/2023]
Abstract
Graves' hyperthyroidism, a common autoimmune disease caused by pathogenic autoantibodies to the thyrotropin (TSH) receptor (TSHR), can be treated but not cured. This single autoantigenic target makes Graves' disease a prime candidate for Ag-specific immunotherapy. Previously, in an induced mouse model, injecting TSHR A-subunit protein attenuated hyperthyroidism by diverting pathogenic TSHR Abs to a nonfunctional variety. In this study, we explored the possibility of a similar diversion in a mouse model that spontaneously develops pathogenic TSHR autoantibodies, NOD.H2h4 mice with the human (h) TSHR (hTSHR) A-subunit transgene expressed in the thyroid and (shown in this article) the thymus. We hypothesized that such diversion would occur after injection of "inactive" hTSHR A-subunit protein recognized only by nonpathogenic (not pathogenic) TSHR Abs. Surprisingly, rather than attenuating the pre-existing pathogenic TSHR level, in TSHR/NOD.H2h4 mice inactive hTSHR Ag injected without adjuvant enhanced the levels of pathogenic TSH-binding inhibition and thyroid-stimulating Abs, as well as nonpathogenic Abs detected by ELISA. This effect was TSHR specific because spontaneously occurring autoantibodies to thyroglobulin and thyroid peroxidase were unaffected. As controls, nontransgenic NOD.H2h4 mice similarly injected with inactive hTSHR A-subunit protein unexpectedly developed TSHR Abs, but only of the nonpathogenic variety detected by ELISA. Our observations highlight critical differences between induced and spontaneous mouse models of Graves' disease with implications for potential immunotherapy in humans. In hTSHR/NOD.H2h4 mice with ongoing disease, injecting inactive hTSHR A-subunit protein fails to divert the autoantibody response to a nonpathogenic form. Indeed, such therapy is likely to enhance pathogenic Ab production and exacerbate Graves' disease in humans.
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Affiliation(s)
- Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, CA 90048; and
| | - Bianca Banuelos
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, CA 90048; and
| | - Holly A Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, CA 90048; and
| | - Nicole Hartwig Trier
- Department of Autoimmunology and Biomarkers, Statens Serum Institut, DK-2300 Copenhagen S, Denmark
| | - Sandra M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, CA 90048; and
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10
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Flytzani S, Guerreiro-Cacais AO, N'diaye M, Lindner M, Linington C, Meinl E, Stridh P, Jagodic M, Olsson T. MOG-induced experimental autoimmune encephalomyelitis in the rat species triggers anti-neurofascin antibody response that is genetically regulated. J Neuroinflammation 2015; 12:194. [PMID: 26511327 PMCID: PMC4625640 DOI: 10.1186/s12974-015-0417-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 10/21/2015] [Indexed: 01/08/2023] Open
Abstract
Background Ιn multiple sclerosis (MS), axonal damage leads to permanent neurological disabilities and the spreading of the autoimmune response to axonal antigens is implicated in disease progression. Experimental autoimmune encephalomyelitis (EAE) provides an animal model that mimics MS. Using different EAE models, we investigated the pathophysiological basis of epitope spreading to neurofascin, a protein localized at the node of Ranvier and its regulation by non-MHC genes. Methods We used two different EAE models in DA rat; one which is induced with myelin oligodendrocyte glycoprotein (MOG) which leads to disease characterized by profound demyelination, and the second which is induced with myelin basic protein (MBP) peptide 63–88 which results in severe central nervous system (CNS) inflammation but little or no demyelination. We determined anti-neurofascin antibody levels during the course of disease. Furthermore, the anti-neurofascin IgG response was correlated with clinical parameters in 333 (DAxPVG.1AV1) x DA rats on which we performed linkage analysis to determine if epitope spreading to neurofascin was affected by non-MHC genes. Results Spreading of the antibody response to neurofascin occurred in demyelinating MOG-induced EAE but not in EAE induced with MBP peptide 63–88. Anti-neurofascin IgG levels correlated with disease severity in (DAxPVG.1AV1) x DA rats, and a genomic region on chromosome 3 was found to influence this response. Conclusions Inter-molecular epitope spreading to neurofascin correlates with disease severity in MOG-EAE is dependent on extensive demyelination and is influenced by non-MHC genes. The findings presented here may shed light on factors involved in the severity of MS and its genetics. Electronic supplementary material The online version of this article (doi:10.1186/s12974-015-0417-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sevasti Flytzani
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, CMM L8:04, Stockholm, Sweden.
| | - Andre Ortlieb Guerreiro-Cacais
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, CMM L8:04, Stockholm, Sweden.
| | - Marie N'diaye
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, CMM L8:04, Stockholm, Sweden.
| | - Maren Lindner
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK.
| | - Christopher Linington
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK.
| | - Edgar Meinl
- Institute of Clinical Neuroimmunology, Ludwig-Maximilians-Universität, Munich, Germany.
| | - Pernilla Stridh
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, CMM L8:04, Stockholm, Sweden.
| | - Maja Jagodic
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, CMM L8:04, Stockholm, Sweden.
| | - Tomas Olsson
- Center for Molecular Medicine, Department of Clinical Neuroscience, Karolinska Institutet, CMM L8:04, Stockholm, Sweden.
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Abstract
PURPOSE OF REVIEW The purpose of this article is to summarize the recent advances on experimental Graves' hyperthyroidism and orbitopathy as studied in two widely used mouse models, which involve repetitive genetic vaccinations using either adenovirus or in-vivo electroporation of the eukaryotic expression plasmid expressing the thyrotropin receptor (TSHR) as a vector. RECENT FINDINGS The models have been improved by using different types of antigens, including the holo receptor, the receptor A-subunit, an alternatively spliced form of variant receptor lacking a single leucine-rich repeat in the codomain, the receptors of human or mouse origin; different mice such as wild-type, TSHR knockout, TSHR transgenic and different inbred mice; and different immunization protocols. They are now useful for elucidating the pathogenic mechanisms of not only Graves' hyperthyroidism but also Graves' orbitopathy. SUMMARY This review summarizes the literature of mouse models of Graves' hyperthyroidism and orbitopathy published over the last 3 years.
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Affiliation(s)
- Yuji Nagayama
- aDepartment of Molecular Medicine, Atomic Bomb Disease Institute, Nagasaki University bDepartment of Endocrinology and Metabolism, Unit of Translational Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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12
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Navarro Alvarez N, Zhu A, Arellano RS, Randolph MA, Duggan M, Scott Arn J, Huang CA, Sachs DH, Vagefi PA. Postnatal xenogeneic B-cell tolerance in swine following in utero intraportal antigen exposure. Xenotransplantation 2015; 22:368-78. [PMID: 26314946 DOI: 10.1111/xen.12186] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Accepted: 08/03/2015] [Indexed: 12/11/2022]
Abstract
BACKGROUND The objective of this study was to investigate the humoral immune response to xenogeneic antigens administered during the fetal state utilizing a baboon-to-pig model. METHODS Nine fetuses from an alpha-1,3-galactosyltransferase gene knockout (GalT-KO) MGH-miniature swine sow underwent transuterine ultrasound-guided intraportal injection of T-cell depleted baboon bone marrow (B-BM) at mid-gestation. Two juvenile GalT-KO swine undergoing direct B-BM intraportal injection were used as controls. RESULTS Postnatal humoral tolerance was induced in the long-term surviving piglets as demonstrated by the absence of any antibody response to baboon donor cells. In addition, a second intraportal B-BM administration at 2.5 months post-birth led to no antibody formation despite re-exposure to xenogeneic antigens. This B-cell unresponsiveness was abrogated only when the animal was exposed subcutaneously to third-party xenogeneic and allogeneic antigens, suggesting that the previously achieved humoral non-responsiveness was donor specific. In comparison, the two juvenile GalT-KO control swine demonstrated increasing anti-baboon IgM and IgG levels following intraportal injection. CONCLUSIONS In summary, xenogeneic B-cell tolerance was induced through in utero intraportal exposure to donor cells and this tolerance persisted following postnatal rechallenge with donor B-BM, but was lost on exposure to third-party antigen, possibly as a result of cross-reactive antibody formation.
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Affiliation(s)
- Nalu Navarro Alvarez
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Alexander Zhu
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Ronald S Arellano
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Mark A Randolph
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Michael Duggan
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - John Scott Arn
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Christene A Huang
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - David H Sachs
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Parsia A Vagefi
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
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Rapoport B, Aliesky HA, Banuelos B, Chen CR, McLachlan SM. A unique mouse strain that develops spontaneous, iodine-accelerated, pathogenic antibodies to the human thyrotrophin receptor. THE JOURNAL OF IMMUNOLOGY 2015; 194:4154-61. [PMID: 25825442 DOI: 10.4049/jimmunol.1500126] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/24/2015] [Indexed: 11/19/2022]
Abstract
Abs that stimulate the thyrotropin receptor (TSHR), the cause of Graves' hyperthyroidism, only develop in humans. TSHR Abs can be induced in mice by immunization, but studying pathogenesis and therapeutic intervention requires a model without immunization. Spontaneous, iodine-accelerated, thyroid autoimmunity develops in NOD.H2(h4) mice associated with thyroglobulin and thyroid-peroxidase, but not TSHR, Abs. We hypothesized that transferring the human TSHR A-subunit to NOD.H2(h4) mice would result in loss of tolerance to this protein. BALB/c human TSHR A-subunit mice were bred to NOD.H2(h4) mice, and transgenic offspring were repeatedly backcrossed to NOD.H2(h4) mice. All offspring developed Abs to thyroglobulin and thyroid-peroxidase. However, only TSHR-transgenic NOD.H2(h4) mice (TSHR/NOD.H2(h4)) developed pathogenic TSHR Abs as detected using clinical Graves' disease assays. As in humans, TSHR/NOD.H2(h4) female mice were more prone than male mice to developing pathogenic TSHR Abs. Fortunately, in view of the confounding effect of excess thyroid hormone on immune responses, spontaneously arising pathogenic human TSHR Abs cross-react poorly with the mouse TSHR and do not cause thyrotoxicosis. In summary, the TSHR/NOD.H2(h4) mouse strain develops spontaneous, iodine-accelerated, pathogenic TSHR Abs in female mice, providing a unique model to investigate disease pathogenesis and test novel TSHR Ag-specific immunotherapies aimed at curing Graves' disease in humans.
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Affiliation(s)
- Basil Rapoport
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute/David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90048
| | - Holly A Aliesky
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute/David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90048
| | - Bianca Banuelos
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute/David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90048
| | - Chun-Rong Chen
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute/David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90048
| | - Sandra M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute/David Geffen School of Medicine at University of California, Los Angeles, Los Angeles, CA 90048
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Evidence that MHC I-E dampens thyroid autoantibodies and prevents spreading to a second thyroid autoantigen in I-A(k) NOD mice. Genes Immun 2015; 16:268-74. [PMID: 25811933 PMCID: PMC4457582 DOI: 10.1038/gene.2015.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 01/07/2015] [Accepted: 01/09/2015] [Indexed: 11/08/2022]
Abstract
NOD.H2k and NOD.H2h4 mice carry the MHC class II molecule I-Ak associated with susceptibility to experimentally-induced thyroiditis. Dietary iodine enhanced spontaneous thyroid autoimmunity, well known in NOD.H2h4 mice, has not been investigated in NOD.H2k mice. We compared NOD.H2h4 and NOD.H2k strains for thyroiditis and autoantibodies to thyroglobulin (TgAb) and thyroid peroxidase (TPOAb) without or with dietary sodium iodide (NaI) for up to 32 weeks. TgAb levels were significantly higher in NOD.H2h4 than NOD.H2k mice on NaI and TPOAb developed in NOD.H2h4 but not NOD.H2k mice. DNA exome analysis revealed, in addition to the differences in the chromosome (Chr) 17 MHC regions, that NOD.H2k and particularly NOD.H2h4 mice have substantial non-MHC parental DNA. KEGG pathway-analysis highlighted thyroid autoimmunity and immune-response genes on Chr 17 but not on Chr 7 and 15 parental B10.A4R DNA. Studies of parental strains provided no evidence for non-MHC gene contributions. The exon 10 thyroglobulin haplotype, associated with experimentally-induced thyroiditis, is absent in NOD.H2h4 and NOD.H2k mice and is not a marker for spontaneous murine thyroid autoimmunity. In conclusion, the absence of I-E is a likely explanation for the difference between NOD.H2h4 and NOD.H2k mice in TgAb levels and, as in humans, autoantibody spreading to TPO.
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Bailey-Kellogg C, Gutiérrez AH, Moise L, Terry F, Martin WD, De Groot AS. CHOPPI: a web tool for the analysis of immunogenicity risk from host cell proteins in CHO-based protein production. Biotechnol Bioeng 2014; 111:2170-82. [PMID: 24888712 PMCID: PMC4282101 DOI: 10.1002/bit.25286] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 04/14/2014] [Accepted: 05/07/2014] [Indexed: 02/04/2023]
Abstract
Despite high quality standards and continual process improvements in manufacturing, host cell protein (HCP) process impurities remain a substantial risk for biological products. Even at low levels, residual HCPs can induce a detrimental immune response compromising the safety and efficacy of a biologic. Consequently, advanced-stage clinical trials have been cancelled due to the identification of antibodies against HCPs. To enable earlier and rapid assessment of the risks in Chinese Hamster Ovary (CHO)-based protein production of residual CHO protein impurities (CHOPs), we have developed a web tool called CHOPPI, for CHO Protein Predicted Immunogenicity. CHOPPI integrates information regarding the possible presence of CHOPs (expression and secretion) with characterizations of their immunogenicity (T cell epitope count and density, and relative conservation with human counterparts). CHOPPI can generate a report for a specified CHO protein (e.g., identified from proteomics or immunoassays) or characterize an entire specified subset of the CHO genome (e.g., filtered based on confidence in transcription and similarity to human proteins). The ability to analyze potential CHOPs at a genomic scale provides a baseline to evaluate relative risk. We show here that CHOPPI can identify clear differences in immunogenicity risk among previously validated CHOPs, as well as identify additional “risky” CHO proteins that may be expressed during production and induce a detrimental immune response upon delivery. We conclude that CHOPPI is a powerful tool that provides a valuable computational complement to existing experimental approaches for CHOP risk assessment and can focus experimental efforts in the most important directions. Biotechnol. Bioeng. 2014;111: 2170–2182.
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McLachlan SM, Rapoport B. Breaking tolerance to thyroid antigens: changing concepts in thyroid autoimmunity. Endocr Rev 2014; 35:59-105. [PMID: 24091783 PMCID: PMC3895862 DOI: 10.1210/er.2013-1055] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 09/24/2013] [Indexed: 02/06/2023]
Abstract
Thyroid autoimmunity involves loss of tolerance to thyroid proteins in genetically susceptible individuals in association with environmental factors. In central tolerance, intrathymic autoantigen presentation deletes immature T cells with high affinity for autoantigen-derived peptides. Regulatory T cells provide an alternative mechanism to silence autoimmune T cells in the periphery. The TSH receptor (TSHR), thyroid peroxidase (TPO), and thyroglobulin (Tg) have unusual properties ("immunogenicity") that contribute to breaking tolerance, including size, abundance, membrane association, glycosylation, and polymorphisms. Insight into loss of tolerance to thyroid proteins comes from spontaneous and induced animal models: 1) intrathymic expression controls self-tolerance to the TSHR, not TPO or Tg; 2) regulatory T cells are not involved in TSHR self-tolerance and instead control the balance between Graves' disease and thyroiditis; 3) breaking TSHR tolerance involves contributions from major histocompatibility complex molecules (humans and induced mouse models), TSHR polymorphism(s) (humans), and alternative splicing (mice); 4) loss of tolerance to Tg before TPO indicates that greater Tg immunogenicity vs TPO dominates central tolerance expectations; 5) tolerance is induced by thyroid autoantigen administration before autoimmunity is established; 6) interferon-α therapy for hepatitis C infection enhances thyroid autoimmunity in patients with intact immunity; Graves' disease developing after T-cell depletion reflects reconstitution autoimmunity; and 7) most environmental factors (including excess iodine) "reveal," but do not induce, thyroid autoimmunity. Micro-organisms likely exert their effects via bystander stimulation. Finally, no single mechanism explains the loss of tolerance to thyroid proteins. The goal of inducing self-tolerance to prevent autoimmune thyroid disease will require accurate prediction of at-risk individuals together with an antigen-specific, not blanket, therapeutic approach.
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Affiliation(s)
- Sandra M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Research Institute, and University of California-Los Angeles School of Medicine, Los Angeles, California 90048
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Collado JA, Guitart C, Ciudad MT, Alvarez I, Jaraquemada D. The Repertoires of Peptides Presented by MHC-II in the Thymus and in Peripheral Tissue: A Clue for Autoimmunity? Front Immunol 2013; 4:442. [PMID: 24381570 PMCID: PMC3865459 DOI: 10.3389/fimmu.2013.00442] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 11/26/2013] [Indexed: 11/13/2022] Open
Abstract
T-cell tolerance to self-antigens is established in the thymus through the recognition by developing thymocytes of self-peptide-MHC complexes and induced and maintained in the periphery. Efficient negative selection of auto-reactive T cells in the thymus is dependent on the in situ expression of both ubiquitous and tissue-restricted self-antigens and on the presentation of derived peptides. Weak or inadequate intrathymic expression of self-antigens increases the risk to generate an autoimmune-prone T-cell repertoire. Indeed, even small changes of self-antigen expression in the thymus affect negative selection and increase the predisposition to autoimmunity. Together with other mechanisms, tolerance is maintained in the peripheral lymphoid organs via the recognition by mature T cells of a similar set of self-peptides in homeostatic conditions. However, non-lymphoid peripheral tissue, where organ-specific autoimmunity takes place, often have differential functional processes that may lead to the generation of epitopes that are absent or non-presented in the thymus. These putative differences between peptides presented by MHC molecules in the thymus and in peripheral tissues might be a major key to the initiation and maintenance of autoimmune conditions.
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Affiliation(s)
- Javier A Collado
- Department of Cell Biology, Physiology and Immunology, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Carolina Guitart
- Department of Cell Biology, Physiology and Immunology, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona , Barcelona , Spain
| | - M Teresa Ciudad
- Department of Cell Biology, Physiology and Immunology, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Iñaki Alvarez
- Department of Cell Biology, Physiology and Immunology, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona , Barcelona , Spain
| | - Dolores Jaraquemada
- Department of Cell Biology, Physiology and Immunology, Institut de Biotecnologia i de Biomedicina, Universitat Autònoma de Barcelona , Barcelona , Spain
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