1
|
Chen Y, Liu S, Gong W, Guo P, Xue F, Zhou X, Wang S, Yuan Z. Protein-centric omics integration analysis identifies candidate plasma proteins for multiple autoimmune diseases. Hum Genet 2023:10.1007/s00439-023-02627-0. [PMID: 38143258 DOI: 10.1007/s00439-023-02627-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Accepted: 11/28/2023] [Indexed: 12/26/2023]
Abstract
It remains challenging to translate the findings from genome-wide association studies (GWAS) of autoimmune diseases (AIDs) into interventional targets, presumably due to the lack of knowledge on how the GWAS risk variants contribute to AIDs. In addition, current immunomodulatory drugs for AIDs are broad in action rather than disease-specific. We performed a comprehensive protein-centric omics integration analysis to identify AIDs-associated plasma proteins through integrating protein quantitative trait loci datasets of plasma protein (1348 proteins and 7213 individuals) and totally ten large-scale GWAS summary statistics of AIDs under a cutting-edge systematic analytic framework. Specifically, we initially screened out the protein-AID associations using proteome-wide association study (PWAS), followed by enrichment analysis to reveal the underlying biological processes and pathways. Then, we performed both Mendelian randomization (MR) and colocalization analyses to further identify protein-AID pairs with putatively causal relationships. We finally prioritized the potential drug targets for AIDs. A total of 174 protein-AID associations were identified by PWAS. AIDs-associated plasma proteins were significantly enriched in immune-related biological process and pathways, such as inflammatory response (P = 3.96 × 10-10). MR analysis further identified 97 protein-AID pairs with potential causal relationships, among which 21 pairs were highly supported by colocalization analysis (PP.H4 > 0.75), 10 of 21 were the newly discovered pairs and not reported in previous GWAS analyses. Further explorations showed that four proteins (TLR3, FCGR2A, IL23R, TCN1) have corresponding drugs, and 17 proteins have druggability. These findings will help us to further understand the biological mechanism of AIDs and highlight the potential of these proteins to develop as therapeutic targets for AIDs.
Collapse
Affiliation(s)
- Yingxuan Chen
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Shuai Liu
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Weiming Gong
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Ping Guo
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Fuzhong Xue
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China
| | - Xiang Zhou
- Department of Biostatistics, University of Michigan, Ann Arbor, MI, 48109, USA
- Center for Statistical Genetics, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Shukang Wang
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China.
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China.
| | - Zhongshang Yuan
- Department of Biostatistics, School of Public Health, Cheeloo College of Medicine, Shandong University, 44, Wenhua West Road, Jinan, 250012, Shandong, China.
- Institute for Medical Dataology, Shandong University, 12550, Erhuan East Road, Jinan, 250003, Shandong, China.
| |
Collapse
|
2
|
Kyrilli A, Unuane D, Poppe KG. Thyroid autoimmunity and pregnancy in euthyroid women. Best Pract Res Clin Endocrinol Metab 2023; 37:101632. [PMID: 35256265 DOI: 10.1016/j.beem.2022.101632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Women with thyroid autoimmunity (TAI), predominately characterized by increased levels of thyroid peroxidase antibody (TPOAb), are at risk for developing pregnancy related complications. In this review, we discuss the importance of TAI during natal and perinatal stages. Before pregnancy, TAI is associated with higher mean serum TSH levels and certain causes of subfertility. During pregnancy, TAI increases the risk of an insufficient response of the thyroid to an increasing strain induced by pregnancy, and consequently (subclinical) hypothyroidism might develop. Euthyroid women with TAI have a higher rate of maternal and foetal complications, but it seems that causality cannot be pinned down to thyroid dysfunction alone. Almost half of the women known with TAI prior to pregnancy will also develop post-partum thyroiditis (PPT). However, any relation between PPT and post-partum depression remains uncertain. More research is required to explain possible associations between TAI and pregnancy morbidities, and studies should focus on a better understanding of TAI as such. Given the many unanswered questions, at present, it is not recommended to screen all (potentially) pregnant women for the presence of TAI.
Collapse
Affiliation(s)
- Aglaia Kyrilli
- Department of Endocrinology, Hôpital Erasme (Université Libre de Bruxelles, ULB), Route de Lennik, 808, 1070, Brussels, Belgium
| | - David Unuane
- Department of Endocrinology, Universitair Ziekenhuis Brussel, UZ Brussel, (Vrije Universiteit Brussel, VUB), Laarbeeklaan, 101, 1090, Brussels, Belgium
| | - Kris G Poppe
- Department of Endocrinology, CHU Saint-Pierre (Université Libre de Bruxelles, ULB), Rue Haute, 322, 1000, Brussels, Belgium.
| |
Collapse
|
3
|
Epstein-Barr Virus Reactivation-Induced Immunoglobulin Production: Significance on Autoimmunity. Microorganisms 2020; 8:microorganisms8121875. [PMID: 33260824 PMCID: PMC7760294 DOI: 10.3390/microorganisms8121875] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/17/2020] [Accepted: 11/25/2020] [Indexed: 12/29/2022] Open
Abstract
Epstein–Barr virus (EBV) mainly persists in B cells, which differentiate into antibody-producing cells, and thus, EBV has been implicated in autoimmune diseases. We aimed to describe the EBV reactivation and its relevance to autoimmune disease, focusing on Graves’ disease, which is an autoimmune hyperthyroidism caused by thyrotropin receptor antibodies. Circulating autoreactive B cells that have evaded from the selection have difficulties differentiating to produce antibodies. However, once EBV infects such B cells and reactivates, the B cells may become plasma cells and produce autoantibody. We herein proposed an EBV reactivation-induced Ig production system, which is a distinct pathway from the antibody production system through germinal centers and bone marrow and has the following characteristics: 1. IgM dominance, 2. ubiquitous Ig production, and 3. the rescue of autoreactive B cells, which skews Ig production toward autoantigens. IgM autoantibodies induced by EBV reactivation may activate the classical complement pathway and injure healthy tissue, which supply autoantigens for the production of affinity-matured IgG autoantibodies. Antibodies induced by EBV reactivation may play important roles in the development and exacerbation of autoimmune diseases.
Collapse
|
4
|
Luo B, Yuan X, Wang W, Zhang J, Liu R, Hu W, Qi X, Xiang N, Chen L. Ocular Manifestations and Clinical Implications of Serum Immunoglobulin G4 Levels in Graves’ Ophthalmopathy Patients. Ocul Immunol Inflamm 2020; 30:580-587. [PMID: 33054491 DOI: 10.1080/09273948.2020.1826537] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Ban Luo
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xu Yuan
- Department of Laboratory Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Wei Wang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jing Zhang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Rong Liu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Weikun Hu
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Xin Qi
- Department of Ophthalmology, the Second Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Nan Xiang
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Liwen Chen
- Department of Ophthalmology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| |
Collapse
|
5
|
Abstract
Autoantibodies (Ab) against the thyroid-stimulating hormone receptor (TSHR) are frequently found in autoimmune thyroid disease (AITD). Autoantibodies to the TSHR (anti-TSHR-Ab) may mimic or block the action of TSH or be functionally neutral. Measurement of anti-TSHR-Ab can be done either via competitive-binding immunoassays or with functional cell-based bioassays. Antibody-binding assays do not assess anti-TSHR-Ab functionality, but rather measure the concentration of total anti-TSHR binding activity. In contrast, functional cell-based bioassays indicate whether anti-TSHR-Ab have stimulatory or blocking activity. Historically bioassays for anti-TSHR-Ab were research tools and were used to study the pathophysiology of Graves' disease and Hashimoto's thyroiditis. In the past, bioassays for anti-TSHR-Abs were laborious and time-consuming and varied widely in performance from laboratory to laboratory. Recent advances in the development of cell-based assays, including the application of molecular engineering, have led to significant improvements that have enabled bioassays to be employed routinely in clinical laboratories. The prevalence and functional significance of TSHR blocking autoantibodies (TBAb) in autoimmune hypothyroidism has been less well investigated compared to TSHR stimulating Ab. There is an increasing body of data, however, that demonstrate the clinical utility and relevance of TBAb, and thus the importance of TBAb bioassays, in the diagnosis and management of patients with AITD. In the present review, we summarize the different methods used to measure TBAb, and discuss their prevalence and clinical relevance.
Collapse
Affiliation(s)
- Tanja Diana
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University (JGU) Medical Center, Mainz, Germany
| | - Paul D. Olivo
- Department of Molecular Microbiology, Washington University Medical School, St. Louis, Missouri, USA
| | - George J. Kahaly
- Molecular Thyroid Research Laboratory, Department of Medicine I, Johannes Gutenberg University (JGU) Medical Center, Mainz, Germany
- Correspondence Prof. George J. Kahaly JGU Medical CenterLangenbeckstraße 155131 MainzGermany+49-6131-17-2290+49-6131-17-3460
| |
Collapse
|
6
|
Fröhlich E, Wahl R. Thyroid Autoimmunity: Role of Anti-thyroid Antibodies in Thyroid and Extra-Thyroidal Diseases. Front Immunol 2017; 8:521. [PMID: 28536577 PMCID: PMC5422478 DOI: 10.3389/fimmu.2017.00521] [Citation(s) in RCA: 224] [Impact Index Per Article: 32.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/19/2017] [Indexed: 12/17/2022] Open
Abstract
Autoimmune diseases have a high prevalence in the population, and autoimmune thyroid disease (AITD) is one of the most common representatives. Thyroid autoantibodies are not only frequently detected in patients with AITD but also in subjects without manifest thyroid dysfunction. The high prevalence raises questions regarding a potential role in extra-thyroidal diseases. This review summarizes the etiology and mechanism of AITD and addresses prevalence of antibodies against thyroid peroxidase, thyroid-stimulating hormone receptor (TSHR), and anti-thyroglobulin and their action outside the thyroid. The main issues limiting the reliability of the conclusions drawn here include problems with different specificities and sensitivities of the antibody detection assays employed, as well as potential confounding effects of altered thyroid hormone levels, and lack of prospective studies. In addition to the well-known effects of TSHR antibodies on fibroblasts in Graves' disease (GD), studies speculate on a role of anti-thyroid antibodies in cancer. All antibodies may have a tumor-promoting role in breast cancer carcinogenesis despite anti-thyroid peroxidase antibodies having a positive prognostic effect in patients with overt disease. Cross-reactivity with lactoperoxidase leading to induction of chronic inflammation might promote breast cancer, while anti-thyroid antibodies in manifest breast cancer might be an indication for a more active immune system. A better general health condition in older women with anti-thyroid peroxidase antibodies might support this hypothesis. The different actions of the anti-thyroid antibodies correspond to differences in cellular location of the antigens, titers of the circulating antibodies, duration of antibody exposure, and immunological mechanisms in GD and Hashimoto's thyroiditis.
Collapse
Affiliation(s)
- Eleonore Fröhlich
- Internal Medicine (Department of Endocrinology and Diabetology, Angiology, Nephrology and Clinical Chemistry), University of Tuebingen, Tuebingen, Germany
- Center for Medical Research, Medical University Graz, Graz, Austria
| | - Richard Wahl
- Internal Medicine (Department of Endocrinology and Diabetology, Angiology, Nephrology and Clinical Chemistry), University of Tuebingen, Tuebingen, Germany
| |
Collapse
|
7
|
McLachlan SM, Rapoport B. Thyrotropin-blocking autoantibodies and thyroid-stimulating autoantibodies: potential mechanisms involved in the pendulum swinging from hypothyroidism to hyperthyroidism or vice versa. Thyroid 2013; 23:14-24. [PMID: 23025526 PMCID: PMC3539254 DOI: 10.1089/thy.2012.0374] [Citation(s) in RCA: 125] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND Thyrotropin receptor (TSHR) antibodies that stimulate the thyroid (TSAb) cause Graves' hyperthyroidism and TSHR antibodies which block thyrotropin action (TBAb) are occasionally responsible for hypothyroidism. Unusual patients switch from TSAb to TBAb (or vice versa) with concomitant thyroid function changes. We have examined case reports to obtain insight into the basis for "switching." SUMMARY TBAb to TSAb switching occurs in patients treated with levothyroxine (LT4); the reverse switch (TBAb to TSAb) occurs after anti-thyroid drug therapy; TSAb/TBAb alterations may occur during pregnancy and are well recognized in transient neonatal thyroid dysfunction. Factors that may impact the shift include: (i) LT4 treatment, usually associated with decreased thyroid autoantibodies, in unusual patients induces or enhances thyroid autoantibody levels; (ii) antithyroid drug treatment decreases thyroid autoantibody levels; (iii) hyperthyroidism can polarize antigen-presenting cells, leading to impaired development of regulatory T cells, thereby compromising control of autoimmunity; (iv) immune-suppression/hemodilution reduces thyroid autoantibodies during pregnancy and rebounds postpartum; (v) maternally transferred IgG transiently impacts thyroid function in neonates until metabolized; (vi) a Graves' disease model involving immunizing TSHR-knockout mice with mouse TSHR-adenovirus and transfer of TSHR antibody-secreting splenocytes to athymic mice demonstrates the TSAb to TBAb shift, paralleling the outcome of maternally transferred "term limited" TSHR antibodies in neonates. Finally, perhaps most important, as illustrated by dilution analyses of patients' sera in vitro, TSHR antibody concentrations and affinities play a critical role in switching TSAb and TBAb functional activities in vivo. CONCLUSIONS Switching between TBAb and TSAb (or vice versa) occurs in unusual patients after LT4 therapy for hypothyroidism or anti-thyroid drug treatment for Graves' disease. These changes involve differences in TSAb versus TBAb concentrations, affinities and/or potencies in individual patients. Thus, anti-thyroid drugs or suppression/hemodilution in pregnancy reduce initially low TSAb levels even further, leading to TBAb dominance. In contrast, TSAb emergence after LT4 administration may be sufficient to counteract TBAb inhibition. The occurrence of "switching" emphasizes the need for careful patient monitoring and management. Finally, whole genome screening of relatively rare "switch" patients and appropriate Graves' and Hashimoto's controls could provide unexpected and valuable information regarding the basis for thyroid autoimmunity.
Collapse
Affiliation(s)
- Sandra M McLachlan
- Thyroid Autoimmune Disease Unit, Cedars-Sinai Medical Center and UCLA School of Medicine, Los Angeles, California 90048, USA.
| | | |
Collapse
|
8
|
Gregoric E, Gregoric JA, Guarneri F, Benvenga S. Injections of Clostridium botulinum neurotoxin A may cause thyroid complications in predisposed persons based on molecular mimicry with thyroid autoantigens. Endocrine 2011; 39:41-7. [PMID: 21061092 DOI: 10.1007/s12020-010-9410-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/06/2010] [Accepted: 10/04/2010] [Indexed: 12/21/2022]
Abstract
A woman with Hashimoto's thyroiditis, under replacement L-T4, repeatedly experienced, over a 10-year period, elevations of serum TSH after eyelid injections of Clostridium botulinum neurotoxin A (Btx). We hypothesized a link between Btx injections and TSH elevations via molecular mimicry, and aimed to verify our hypothesis. Using an in silico approach, we searched first for amino acid sequence homology between Btx and thyroid autoantigens, and next for HLA binding motifs within homologous segments. We found that (i) Btx and thyroid autoantigens share amino acid sequence homology; (ii) some homologous regions contain epitopes of both Btx and thyroid autoantigens; (iii) some of such regions contain HLA-DR3 and/or HLA-DR7 binding motifs, which predominate over other HLA-DRs. This is relevant because the patient's HLA-DR haplotype was DR3/DR7. In conclusion, clinical and bioinformatics data suggest a possible pathogenetic link between Btx and autoimmune thyroid diseases. Considering the wide and increasing medical and dermocosmetic use of Btx, and the frequently subclinical course of autoimmune thyroid diseases, we think that thyroid "complications" may pass frequently undetected in Btx-treated persons.
Collapse
Affiliation(s)
- Edvina Gregoric
- Department of Nuclear Medicine, Hospital Izola, Izola, Slovenia
| | | | | | | |
Collapse
|
9
|
Nikolić A, Micić D, Nikolić D, Stanimirović V. [TRAb determination in newly detected patients with hyperthyroidism and their prognostic importance]. MEDICINSKI PREGLED 2009; 62:304-307. [PMID: 19902779 DOI: 10.2298/mpns0908304n] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
INTRODUCTION In more than 50 years since the first demonstration of the immune basis for thyroiditis was done, the autoimmune disease has been identified as a major cause of disfunction of all endocrine organs. Identification of the antithyroid with the radioreceptor assay is widespread in clinical use for differential diagnosis of other thyroid disorders manifesting with the hyperthyroidism. MATERIAL AND METHODS Our study included 44 patients with new onset Graves disease which was primarily verified according to the objective status of the patients (signs of hyperthyroidism), biochemical parameters (which included thyroid hormones) and detection of the TRAb (TSAb- thyreotropin-stimulating antibodies) at the beginning of diagnosis and in the first, second and after the third month since the introduction of antithyroid therapy (propiltiouracil). RESULTS On the basis of the TSAb concentration level, we found that the response to the therapy was positive in 65.9% ("responders") of the patients and negative in 22.7% ("non responders") of the patients and without therapeutic effect were 11.4% of the patients. During the therapy (after the first month), in the group of non responders we found increased values of the TSAb (p<0.05) and in the group of responders we found reduction of the TSAb levels (p<0.05). CONCLUSION Our study demonstrated that the therapy with propiltiouracil, after the first month divide patients with positive and negative response, which could change the therapeutic, options in the future.
Collapse
|
10
|
Carella C, Mazziotti G, Sorvillo F, Piscopo M, Cioffi M, Pilla P, Nersita R, Iorio S, Amato G, Braverman LE, Roti E. Serum thyrotropin receptor antibodies concentrations in patients with Graves' disease before, at the end of methimazole treatment, and after drug withdrawal: evidence that the activity of thyrotropin receptor antibody and/or thyroid response modify during the observation period. Thyroid 2006; 16:295-302. [PMID: 16571093 DOI: 10.1089/thy.2006.16.295] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
AIM AND METHODS We performed a quantitative retrospective analysis of serum thyrotropin receptor antibody (TRAb) concentrations measured by a second-generation radioreceptor assay in 58 patients with Graves' disease (GD) at the onset of the disease, at the end of 18 month methimazole (MMI) treatment, and after MMI withdrawal in order to evaluate the correlation between the presence of these antibodies and the relapse of hyperthyroidism. Sixty healthy subjects were enrolled as a control group. RESULTS Before MMI treatment the best cutoff TRAb value for identifying patients with GD was 1.45 UI/L (specificity, 100%; sensitivity, 98.3%). At the end of MMI treatment, serum TRAb concentrations were significantly lower (p < 0.001) than those measured at baseline, but they were still significantly higher (p < 0.001) than those found in the control subjects. At the end of MMI treatment, 44 patients (75.9%) had positive TRAb values (>1.45 UI/L). After MMI withdrawal (median, 15 months), 34 patients (58.6%) became hyperthyroid, 4 patients (6.9%) became hypothyroid, and 20 patients (34.5%) remained euthyroid. There was a significant correlation between serum TRAb concentrations at the end of MMI treatment and the percentage of patients who became hyperthyroid (r: 0.56; p < 0.001) and the time of appearance of hyperthyroidism (r: -0.38; p = 0.03). All 4 patients with TRAb values below 0.9 UI/L at the end of MMI treatment remained euthyroid throughout the follow-up period. Among the 27 patients who had serum TRAb values higher than 4.4 UI/L, 23 developed hyperthyroidism and 4 hypothyroidism. The TRAb values between 0.9 and 4.4 UI/L did not discriminate between the 27 patients (46.6%) who remained euthyroid from those who had relapse of hyperthyroidism. Thus a different TRAb end of treatment cutoff was calculated to identify patients who became again hyperthyroid. This TRAb cutoff value was 3.85 UI/L (sensitivity, 85.3%; specificity, 96.5%). All but 1 patient who had serum TRAb values above 3.85 UI/L became hyperthyroid after MMI was withdrawn (positive predictive value, 96.7%). In these patients, relapse of hyperthyroidism was independent of the changes in serum TRAb concentrations (r: 0.27; p = 0.15) and occurred after a median period of 8 weeks (range, 4-48). Hyperthyroidism also developed in 5 of 24 patients who had serum TRAb concentrations lower than 3.85 UI/L at the end of MMI treatment. In these 5 patients the relapse of hyperthyroidism occurred after a median period of 56 weeks (range, 24-120) and was always accompanied by an increase in serum TRAb concentrations. CONCLUSIONS TRAb persist in the blood of most patients with GD after 18 months of MMI treatment. Both the frequency and the time of appearance of hyperthyroidism are closely correlated with serum TRAb concentrations at the end of MMI treatment. Our data would suggest that TRAb maintain stimulating activity after a full course of MMI treatment in the large majority of patients with GD. However, it is likely that the potency of these antibodies and/or the thyroid response to them change during treatment, as suggested by the different values measured in euthyroid control subjects and in euthyroid patients after MMI treatment.
Collapse
Affiliation(s)
- C Carella
- Department of Clinical and Experimental Medicine F. Magrassi & A. Lanzara, Second University of Naples, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
McLachlan SM. Graves' disease: the T(H)1/T(H)2 paradigm versus the "hygiene" hypothesis and defective immune regulation. Thyroid 2003; 13:127-8. [PMID: 12699602 DOI: 10.1089/105072503321319413] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
12
|
Chazenbalk GD, Pichurin P, Chen CR, Latrofa F, Johnstone AP, McLachlan SM, Rapoport B. Thyroid-stimulating autoantibodies in Graves disease preferentially recognize the free A subunit, not the thyrotropin holoreceptor. J Clin Invest 2002; 110:209-17. [PMID: 12122113 PMCID: PMC151066 DOI: 10.1172/jci15745] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Graves disease is directly caused by thyroid-stimulating autoantibodies (TSAb's) that activate the thyrotropin receptor (TSHR). We observed upon flow cytometry using intact cells that a mouse mAb (3BD10) recognized the TSHR ectodomain with a glycosidylphosphatidylinositol (ECD-GPI) anchor approximately tenfold better than the same ectodomain on the wild-type TSHR, despite the far higher level of expression of the latter. The 3BD10 epitope contains the N-terminal cysteine cluster critical for TSAb action. Consequently, we hypothesized and confirmed that TSAb (but not thyrotropin-blocking autoantibodies [TBAb's]) also poorly recognize the wild-type TSHR relative to the ECD-GPI. Despite poor recognition by TSAb of the holoreceptor, soluble TSHR A subunits (known to be shed from surface TSHR) fully neutralized autoantibody-binding activity. These data indicate that the epitope(s) for TSAb's, but not for TBAb's, are partially sterically hindered on the holoreceptor by the plasma membrane, the serpentine region of the TSHR, or by TSHR dimerization. However, the TSAb epitope on the soluble A subunit is freely accessible. This observation, as well as other evidence, supports the concept that A subunit shedding either initiates or amplifies the autoimmune response to the TSHR, thereby causing Graves disease in genetically susceptible individuals.
Collapse
Affiliation(s)
- Gregorio D Chazenbalk
- Autoimmune Disease Unit, Cedars-Sinai Research Institute and School of Medicine, University of California, Los Angeles, Los Angeles, California, USA
| | | | | | | | | | | | | |
Collapse
|
13
|
Chazenbalk GD, Pichurin P, Chen CR, Latrofa F, Johnstone AP, McLachlan SM, Rapoport B. Thyroid-stimulating autoantibodies in Graves disease preferentially recognize the free A subunit, not the thyrotropin holoreceptor. J Clin Invest 2002. [DOI: 10.1172/jci0215745] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
14
|
Abstract
Although assays to detect thyroid autoantibodies have been available for more than 40 years, their place in the clinical management of thyroid disease has remained controversial; however, novel automated detection techniques using recombinant antigens are increasing the sensitivity and specificity of the assays, particularly for antibodies to the TSH receptor. In addition, new antigenic targets have been defined including the sodium-iodide symporter and four eye muscle proteins targeted in Graves' ophthalmopathy. This article summarizes the immunobiology, assay methodology and prevalence in thyroid diseases of each of the major thyroid autoantibodies before discussing the clinical indications for their use in thyroid diseases.
Collapse
Affiliation(s)
- P Saravanan
- Division of Medicine, University of Bristol, Bristol, United Kingdom
| | | |
Collapse
|
15
|
Nebes V, Wall J. Membrane Receptor–Linked Disease States. Compr Physiol 1998. [DOI: 10.1002/cphy.cp070112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
16
|
Prabhakar BS, Fan JL, Seetharamaiah GS. Thyrotropin-receptor-mediated diseases: a paradigm for receptor autoimmunity. IMMUNOLOGY TODAY 1997; 18:437-42. [PMID: 9293160 DOI: 10.1016/s0167-5699(97)01089-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Autoantibodies to the thyrotropin receptor (TSHR) can act as thyrotropin agonists or antagonists, or can cause thyroid hypertrophy. Neither the autoantibody-binding sites on the TSHR nor the intracellular mechanisms by which the autoantibodies mediate their diverse functional effects are completely understood. This article reviews how cloning of the TSHR has contributed to our understanding of its structure and function, and has allowed induction of experimental autoimmunity to the TSHR.
Collapse
Affiliation(s)
- B S Prabhakar
- Dept of Microbiology and Immunology, University of Texas Medical Branch, Galveston 77555-1019, USA.
| | | | | |
Collapse
|
17
|
Patibandla SA, Prabhakar BS. Autoimmunity to the thyroid stimulating hormone receptor. ADVANCES IN NEUROIMMUNOLOGY 1996; 6:347-57. [PMID: 9183516 DOI: 10.1016/s0960-5428(97)00034-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Thyroid disorders are the most common endocrine diseases and affect a large segment of the population. Most of the thyroid diseases are autoimmune in nature and can be broadly grouped into two categories; one mediated by autoimmune responses to the thyroglobulin (i.e. Hashimoto's thyroiditis), and the other mediated by autoimmunity to the thyrotropin receptor (primarily Graves' disease). Although patients with autoimmune thyroid diseases exhibit immune responses against a number of thyroid antigens, such as thyroglobulin, thyrotropin receptor and thyroid peroxidase, responses directed against a specific antigen appear to play an important role in the disease pathogenesis. For example, Hashimoto's thyroiditis is primarily mediated by T cell responses directed toward the thyroglobulin receptor, whereas Graves' disease is mediated by antibodies directed against the thyrotropin receptor. In this review we will focus on thyroid diseases mediated by autoimmune responses to the thyrotropin receptor.
Collapse
Affiliation(s)
- S A Patibandla
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston 77555, USA
| | | |
Collapse
|