The circulating IL-35+ regulatory B cells are associated with thyroid associated opthalmopathy.

BACKGROUND: Thyroid-associated ophthalmopathy (TAO) is the most common orbital disease in adults, potentially leading to disfigurement and visual impairment. However, the causes of TAO are not fully understood. IL-35+B cells are a newly identified regulatory B cells (Bregs) in maintaining immune balance in various autoimmune diseases. Yet, the influence of IL-35+Bregs in TAO remains unexplored. METHODS: This study enrolled 36 healthy individuals and 14 TAO patients. We isolated peripheral blood mononuclear cells and stimulated them with IL-35 and CpG for 48 h. Flow cytometry was used to measure the percentages of IL-35+Bregs. RESULTS: The percentage of circulating IL-35+Bregs was higher in TAO patients, and this increase correlated positively with disease activity. IL-35 significantly increased the generation of IL-35+Bregs in healthy individuals. However, B cells from TAO patients exhibited potential impairment in transitioning into IL-35+Breg phenotype under IL-35 stimulation. CONCLUSIONS: Our results suggest a potential role of IL-35+Bregs in the development of TAO, opening new avenues for understanding disease mechanisms and developing therapeutic approaches.

Single-cell BCR and transcriptome analysis reveals peripheral immune signatures in patients with thyroid-associated ophthalmopathy.

Thyroid-associated ophthalmopathy (TAO) is the most prevalent orbital disease in adults caused by an autoimmune disorder, which can lead to disfigurement and vision impairment. Developing effective treatments for this condition presents challenges due to our limited understanding of its underlying immune aberrations. In this study, we profiled the immune components in the peripheral blood of patients with TAO as well as healthy individuals, utilizing single-cell RNA sequencing and B-cell receptor repertoires (BCR) analysis. We observed a significant reduction in the proportions of regulatory B cells (Bregs) and type 2 conventional dendritic cells (DCs) in patients with TAO during the active phase. Conversely, there was a significant increase in the proportion of type 1 DCs. Further analysis of cell differentiation trajectory revealed potential impairment in the transition of B cells towards Breg phenotype during the active phase of TAO. Besides, the activation process of TAO appeared to involve inflammation and immune dysfunction, as indicated by the dynamic changes in the activities of key regulators. The abnormalities in the peripheral immune system, such as the reduced capacity of Bregs to suppress inflammation, were primarily driven by the enhanced interaction among Breg, DCs, and monocytes (i.e., CD22-PTPRC and BTLA-TNFRSF14). Collectively, our findings offer a comprehensive insight into the molecular regulation and cellular reconfiguration during the active phase of TAO at the single-cell level, in order to explore the pathogenesis of TAO and provide new ideas for the future treatment of TAO.

Integrated Proteomics and Metabolomics Analyses of Serum in Chinese Patients with Severe and Active Graves' Orbitopathy: A Cross-sectional Study.

OBJECTIVE: The present study aims to investigate the alterations of serum proteomic and metabolomic profiles in Chinese patients with severe and active Graves' Orbitopathy (GO). MATERIALS AND METHODS: Thirty patients with GO and 30 healthy volunteers were enrolled. The serum concentrations of FT3, FT4, T3, T4, and thyroid-stimulating hormone (TSH) were analyzed, after which TMT labeling-based proteomics and untargeted metabolomics were performed. Metabo- Analyst and Ingenuity Pathway Analysis (IPA) was used for integrated network analysis. A nomogram was established based on the model to explore the disease prediction ability of the identified feature metabolites. RESULTS: One hundred thirteen proteins (19 up-regulated and 94 down-regulated) and 75 metabolites (20 increased and 55 decreased) were significantly altered in GO compared to the control group. By combining the lasso regression, IPA network, and protein-metabolite-disease sub-networks, we extracted feature proteins (CPS1, GP1BA, and COL6A1) and feature metabolites (glycine, glycerol 3-phosphate, and estrone sulfate). The logistic regression analysis revealed that the full model with the prediction factors and three identified feature metabolites had better prediction performance for GO compared to the baseline model. The ROC curve also indicated better prediction performance (AUC = 0.933 vs. 0.789). CONCLUSION: A new biomarker cluster combined with three blood metabolites with high statistical power can be used to discriminate patients with GO. These findings provide further insights into the pathogenesis, diagnosis, and potential therapeutic targets for this disease.

Graves' Autoantibodies Exhibit Different Stimulating Activities in Cultures of Thyrocytes and Orbital Fibroblasts Not Reflected by Clinical Assays.

Background: The pathogenesis of Graves' hyperthyroidism (GH) and associated Graves' orbitopathy (GO) appears to involve stimulatory autoantibodies (thyrotropin receptor [TSHR]-stimulating antibodies [TSAbs]) that bind to and activate TSHRs on thyrocytes and orbital fibroblasts. In general, measurement of circulating TSHR antibodies by clinical assays correlates with the status of GH and GO. However, most clinical measurements of TSHR antibodies use competitive binding assays that do not distinguish between TSAbs and antibodies that bind to but do not activate TSHRs. Moreover, clinical assays for TSAbs measure stimulation of only one signaling pathway, the cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) pathway, in engineered cells that are not thyrocytes or orbital fibroblasts. We determined whether measuring TSAbs by a cAMP-PKA readout in engineered cells accurately reveals the efficacies of stimulation by these antibodies on thyrocytes and orbital fibroblasts. Methods: We measured TSAb stimulation of normal human thyrocytes and orbital fibroblasts from patients with GO in primary cultures in vitro. In thyrocytes, we measured secretion of thyroglobulin (TG) and in orbital fibroblasts secretion of hyaluronan (hyaluronic acid [HA]). We also measured stimulation of cAMP production in engineered TSHR-expressing cells in an assay similar to clinical assays. Furthermore, we determined whether there were differences in stimulation of thyrocytes and orbital fibroblasts by TSAbs from patients with GH alone versus from patients with GO understanding that patients with GO have accompanying GH. Results: We found a positive correlation between TSAb stimulation of cAMP production in engineered cells and TG secretion by thyrocytes as well as HA secretion by orbital fibroblasts. However, TSAbs from GH patients stimulated thyrocytes more effectively than TSAbs from GO patients, whereas TSAbs from GO patients were more effective in activating orbital fibroblasts than TSAbs from GH patients. Conclusions: Clinical assays of stimulation by TSAbs measuring activation of the cAMP-PKA pathway do correlate with stimulation of thyrocytes and orbital fibroblasts; however, they do not distinguish between TSAbs from GH and GO patients. In vitro, TSAbs exhibit selectivity in activating TSHRs since TSAbs from GO patients were more effective in stimulating orbital fibroblasts and TSAbs from GH patients were more effective in stimulating thyrocytes.

Predicting the Course of Graves' Orbitopathy Using Serially Measured TSH-Receptor Autoantibodies by Automated Binding Immunoassays and the Functional Bioassay.

The aim of the study was to investigate the use of serial measurements of TSH-receptor autoantibodies (TRAb) with the newest available assay technology to predict the course of Graves' Orbitopathy (GO) during the first 24 months from disease onset. Serial serum samples from patients with GO (103 mild/135 severe) were collected between 2007 and 2017 and retrospectively analyzed. The course of GO were classified into mild/severe 12 months after manifestation (severe: NOSPECS≥5; mild<5). TRAb were measured with automated binding immunoassays (IU/l): TRAb Elecsys (Cobas, Roche), TRAb bridge assay (IMMULITE, Siemens), and a cell-based bioassay (percent of specimen to reference ratio - SRR%) (Thyretain, Quidel). Variable cut off levels of measured TRAb were calculated at specificity of 90% from receiver operator curve (ROC) analysis for several timepoints during the course of GO. To select one: 5-8 months after first GO symptoms, which is the timepoint for usual referals for treatment mild course could be predicted at cut offs of 1.5 IU/l (Elecsys), 0.8 IU/l (Immulite) and 402% SRR (Thyretain) and the risc of severe course has to be anticipated if TRAb are above 11.6 IU/l (Elecsys), 6.5 IU/l (Thyretain), and 714% SRR (Thyretain). The Thyretain bioassay showed the highest diagnostic sensitivity (using the commercial cut off's) over the entire follow up period. TRAb measurements during the 24-month follow up of GO provide added value to the GO clinical activity and severity scores and should be used especially in the event of an unclear decision-taking situation with regard to therapy.

Combination Model of Thyrotrophin Receptor Antibody and Volumetric Orbital Apex Crowding Index as an Indicator of Dysthyroid Optic Neuropathy.

BACKGROUND: Dysthyroid optic neuropathy (DON) is one of the most serious vision-threatening complications of thyroid eye disease (TED); however, accurate and established diagnostic tools for DON are yet lacking. The present study was aimed at identifying new diagnostic factors for the accurate diagnosis of DON. METHODS: This retrospective cross-sectional study included 25 TED patients (50 eyes) with enlarged extraocular muscles, no previous anti-inflammatory therapy, and the absence of other vision-affecting diseases between May 2017 and August 2019. Baseline data, such as gender, age, ophthalmological history, thyroid disease and management, TED history including clinical features, management, and long-term results, ophthalmological examinations, serology examinations, and single-photon emission computed tomography/computed tomography (SPECT/CT) results, were extracted. The diagnostic criteria were as follows: (1) best-corrected visual acuity (BCVA) loss coexisting with either of the following-increased latency or reduction of amplitude on visual evoked potential (VEP), impaired color vision, visual field defects, contrast sensitivity impairment, and optic disk swelling-and (2) Barrett's index ≥ 60% in CT. Univariate and multivariate logistic regression analyses assessed the differences in age, gender, eyes, medical history, clinical activity, thyroid hormone and antibodies, uptake ratio (UR) of extraocular muscles in SPECT/CT, and volumetric orbital apex crowding index (VACI) using the generalized estimation equation. Consequently, the receiver operating characteristic curve (ROC) of the significant factors was constructed. RESULTS: Univariate analysis revealed significant differences in the clinical activity, free triiodothyronine (FT3), free thyroxine (FT4), thyrotrophin receptor antibody (TRAb) levels, the UR of superior and medial rectus, and VACI between DON and TED (without DON) groups. Multivariate regression analysis revealed that TRAb and VACI were significantly different. ROC analysis showed that the univariate models of TRAb or VACI and the multivariate model were effective indicators of DON, while the multivariate model had the highest area under the ROC curve. CONCLUSION: A combination of TRAb and VACI is an effective indicator for DON.

Effect of systemic steroid therapy in Graves' orbitopathy on regulatory T cells and Th17/Treg ratio.

PURPOSE: Glucocorticoids are a mainstay treatment for Graves' orbitopathy, yet their exact mechanisms of action remain unclear. We aimed to determine whether the therapeutic effects of systemic steroid therapy in Graves' orbitopathy are mediated by changes in regulatory T lymphocytes (Tregs) and T helper 17 lymphocytes (Th17). METHODS: We assessed Treg and Th17 levels in the peripheral blood of 32 patients with active, moderate-to-severe Graves' orbitopathy who received 12 weekly pulses of methylprednisolone, and determined their association with disease severity, disease activity, and treatment outcomes. The acute orbitopathy phase was confirmed based on clinical evaluation and magnetic resonance imaging, and assessed using the clinical activity score (CAS). The severity of the disease was classified according to ETA/EUGOGO guidelines, and quantified based on the total eye score. Treatment response was determined based on specific criteria (e.g., changes in CAS score, diplopia grade, visual acuity, etc.). Treg and Th17 cells were identified using flow cytometry. RESULTS: Methylprednisolone treatment improved the activity of the disease and altered the Th17/Treg balance (i.e., the percentage of Tregs decreased while the number of Th17 cells remained unchanged). There was no association between the Treg/Th17 ratio and the activity and severity of the disease or the treatment response. CONCLUSIONS: Therapeutic effects of steroid therapy in Graves' orbitopathy are not mediated by Treg and Th17 alterations in the peripheral blood. The decrease in peripheral Treg percentage is likely a consequence of the non-specific effects of steroids and does not impact clinical outcome.

Altered expression profile of BAFF receptors on peripheral blood B lymphocytes in Graves' disease.

BACKGROUND: B lymphocyte activating factor (BAFF) is a growth factor regulating B lymphocytes survival and maturation. Serum BAFF levels were elevated in patients affected with autoimmune thyroid diseases (AITD), including Graves' disease (GD) and Hashimoto's thyroiditis (HT). The aim of this study is to explore the association of expression levels of BAFF and its receptors with AITD. METHODS: Fifty-two GD patients, 39 Hashimoto's thyroiditis (HT) patients and 23 healthy controls (HC) were recruited in this study. Serum BAFF levels were measured by ELISA. Expression of BAFF receptors, including BAFF receptor 3 (BR3) and transmembrane activator and calcium-modulating and cyclophilin ligand interactor (TACI), on B lymphocytes were analyzed by flowcytometry. Effects of steroids on serum BAFF levels and expression of BR3 and TACI were also observed in 10 patients with Graves' orbitopathy (GO) receiving steroids therapy. RESULTS: Serum BAFF levels were significantly elevated from 0.93 ± 0.24 ng/ml in HC to 1.18 ± 0.33 ng/ml in GD (P = 0.0027) and 1.02 ± 0.24 ng/ml in HT (P = 0.0331). BR3 expression on peripheral B lymphocytes were elevated in GD (mean MFI: 4.52 ± 2.06 in GD vs. 3.00 ± 0.87 in HC, P = 0.0015), while TACI expression on peripheral B lymphocytes were decreased in GD without significance (mean MFI: 7.96 ± 4.06 in GD vs. 9.10 ± 3.37 in HC, P = 0.1285). Expression of BR3 and TACI was not changed significantly in HT patients. Steroids significantly suppressed serum BAFF concentrations (from 1.18 ± 0.27 ng/ml to 0.97 ± 0.10 ng/ml, P = 0.0364) and BR3 expression in GO patients (mean MFI from 6.26 ± 4.91 to 4.05 ± 1.58, P = 0.0083). CONCLUSIONS: Altered expression of BAFF and its receptor may mediate the autoimmunity in GD. Restoring the normal expression profile of receptors for BAFF could be a new strategy to treat GD.

Association between Clinical Activity Score and Serum Interleukin-6, Interleukin-8 and Interleukin-10 during Systemic Glucocorticoid Treatment for Active Moderate-to-Severe Graves' Orbitopathy.

Purpose: Some interleukins (ILs) play an important role in Graves' orbitopathy (GO) pathogenesis. We aimed to compare serum IL-6, IL-8 and IL-10 in GO patients, patients with Graves' disease (GD) without GO and healthy controls (HC); to follow IL changes during glucocorticoid (GC) treatment for GO; to examine associations between ILs and Clinical Activity Score (CAS).Materials and Methods: Thirty-one patients with active moderate-to-severe GO (GO(+) group), 30 patients with GD without GO (GO(-) group) and 30 HC were enrolled. At baseline, ILs were measured in all groups, CAS was evaluated in GO(+) patients, who were then treated with systemic GCs for 12 weeks. ILs and CAS were reassessed after the first week of treatment (W2) and at the end of the therapy (W12).Results: At baseline, IL-6 was significantly higher in GO(+) and GO(-) patients, IL-8 - higher in GO(-) patients and IL-10 - lower in GO(+) patients compared to HC. Baseline ILs did not correlate with CAS. At W2, all ILs and CAS decreased significantly. At W12, CAS decreased further, IL-6 remained low, IL-8 and IL-10 returned to baseline. CAS reduction correlated positively with IL-6 reduction at W12 (ρ = 0.38, p = .04).GO(+) patients with overall CAS reduction≥2 had higher baseline IL-6 (3.4 vs 2.6 pg/ml, p = .15), smaller IL-10 reduction at W2 (10.5 vs 18.2%, p = .09), lower IL-6 (1.4 vs 2.4 pg/ml, p < .01) and higher IL-6 reduction at W12 (48.6 vs 21.4%, p = .01) compared to patients with CAS reduction<2. Logistic regression analysis confirmed that overall CAS reduction≥2 was associated with higher baseline IL-6, lower IL-6 at W12 and smaller IL-10 reduction at W2 (R2 = 0.66).Conclusions: Higher baseline IL-6, lower IL-6 at W12 and smaller IL-10 reduction at W2 were associated with higher probability of significant overall CAS reduction. IL-6 might be a potential additional marker for assessing disease activity.

Beneficial effect of low-dose radioiodine ablation for Graves' orbitopathy: results of a retrospective study.

OBJECTIVE: Graves' orbitopathy (GO) reflects an autoimmune response against antigens expressed by the thyroid and orbital tissues. Elimination of thyroid antigens may be beneficial for GO. Total thyroid ablation (TTA) [thyroidectomy (Tx), followed by 30 mCi of radioiodine] was shown to exert a beneficial effect on GO following intravenous glucocorticoids (ivGC) compared with Tx alone. Here, we investigated retrospectively whether TTA performed with a 15 mCi of radioiodine still maintains advantages over Tx. METHODS: Thirty-two subjects, 13 treated with TTA (performed with 15 mCi of radioiodine) and 19 with Tx alone, all with moderately severe, active GO, treated with ivGC, were studied. The primary objective was the outcome of GO at 24 weeks based on a composite evaluation. RESULTS: The two groups did not differ at baseline in terms of sex, age, smoking habits, TSH, anti-TSH receptor autoantibodies, GO duration and eye features. The proportion of GO responders at 24 weeks was greater in the TTA (61.5%) than in the Tx group (26.3%, P = 0.046). In contrast, GO outcome at 48 weeks did not differ between the two groups (69.2% vs 52.6% of responder in TTA and Tx group, respectively). The outcome of the individual GO features did not differ between the two groups both a 24 and 48 months. CONCLUSIONS: The advantage of total thyroid ablation seems to be a more rapid response for GO to ivGC treatment. Prospective, randomized studies in a larger number of subjects are needed to confirm our findings.

IL-38 Exerts Anti-Inflammatory and Antifibrotic Effects in Thyroid-Associated Ophthalmopathy.

CONTEXT: Thyroid-associated ophthalmopathy (TAO) is an organ-specific autoimmune disease closely associated with Graves' disease. IL-38, a novel cytokine in the IL-1 superfamily, has been reported to be involved in the pathogenesis of various autoimmune diseases. OBJECTIVE: We aimed to evaluate the relationship between IL-38 and TAO disease activity and its role in inflammation and fibrosis in TAO. METHODS: Blood samples and orbital connective tissues were collected from TAO patients and controls. Orbital fibroblasts were isolated from patients with TAO. Enzyme-linked immunosorbent assay, immunohistochemistry, flow cytometry, immunofluorescence, quantitative real-time PCR and Western blot analysis were performed. RESULTS: Here, we demonstrated that IL-38 levels decreased in the circulation and orbital connective tissues of patients with TAO compared with the controls, and levels were negatively correlated with the clinical activity score. In vitro, potent anti-inflammatory and antifibrotic effects of IL-38 were observed. Furthermore, we revealed that IL-38 can counteract the phosphorylation of star molecules in multiple classical pathways. CONCLUSION: IL-38 plays a protective role in TAO and is associated with its pathogenesis. Our data suggest that IL-38 may be a promising marker of TAO disease activity and a potential target for TAO therapy.

Predicting the Relapse of Hyperthyroidism in Treated Graves' Disease with Orbitopathy by Serial Measurements of TSH-Receptor Autoantibodies.

The aim of this study was to investigate the potential of the new TSH-receptor antibody (TRAb) assays to predict remission or relapse of hyperthyroidism in patients with Graves' disease (GD) and Graves' orbitopathy (GO). TRAbs were measured retrospectively in sera from a cohort of GD patients with GO (n=117; remission n=38 and relapse n=79-Essen GO biobank) with automated binding immunoassays: TRAb Elecsys (Cobas Roche) and TRAb bridge assay (IMMULITE, Siemens), and the TSAb (thyroid stimulating Ab) cell-based bioassay (Thyretain, Quidel Corp.). To identify relapse risk/remission of hyperthyroidism patients were followed up at least 10 months after the end of antithyroid drug therapy (ATD) therapy. ROC plot analysis was performed to calculate cut-off levels of TRAb and TSAb for prediction of relapse and remission of hyperthyroidism. Cut-off serum levels are provided for timepoints around 3, 6, 10, and 15 months after the beginning of ATD. Repeated measurements of TRAb increase the rate of relapses predictions to 60% (Elecsys), 70% (IMMULITE), and 55% (Thyretain). Patients with remission have consistently TRAb levels below the cut off for relapse in repeated measurements. The cell-based bioassay was the most sensitive - and continued to be positive during follow up [at 15 months: 90% vs. 70% (IMMULITE) and 65% (Elecsys)]. Identification of relapsing hyperthyroidism is possible with automated immunoassays and cell-based bioassay especially with serial TRAb measurements during the course of ATD therapy. Patient who need eye surgery may profit from an early decision towards definitive treatment.

Percentage of Myeloid Dendritic Cells in Peripheral Venous Blood Is Negatively Related to Incidence of Graves' Orbitopathy.

The aim of the study was to evaluate the distribution of blood dendritic cells (DCs) in patients with Graves' orbitopathy (GO) and to assess the influence of methylprednisolone therapy on subsets of peripheral blood mononuclear cells (PBMCs). Peripheral blood DC subsets were analyzed by flow cytometry in patients with active GO (n = 17), inactive GO (n = 8), and Graves' disease (GD) without GO (n = 8) and controls (n = 15); additionally, in patients with active GO (n = 17), analyses were done at three time points, i.e., before methylprednisolone treatment and after 6 weeks and after 12 weeks of the treatment. Percentage of myeloid DCs (mDCs) in PBMC fraction was significantly lower in patients with both active and inactive GO, compared to patients with GD without GO and controls (p < 0.05). In addition, mDCs were also documented to be an independent factor negatively associated with GO, however without essential differences between active and inactive phases. On the other hand, we did not observe any changes in the percentage of DCs after methylprednisolone therapy (p > 0.05). In the present study, we have succeeded to firstly demonstrate-according to our knowledge-that blood mDCs are negatively related to GO incidence.

Serum thyroglobulin is associated with orbitopathy in Graves' disease.

PURPOSE: Serum thyroglobulin levels are often elevated in Graves' disease (GD) and in most cases decrease during treatment. Its relation to Graves' orbitopathy (GO) has not been clarified. Previously, a risk of GO has been linked to smoking, TSH receptor stimulation, high TSH-receptor antibodies (TRAb), low thyroid peroxidase and thyroglobulin antibodies (TPOAb, TgAb). METHODS: We examined Tg levels in 30 consecutive patients with GD were given drug therapy (methimazole + thyroxine) for up to 24 months. GO was identified by clinical signs and symptoms. 17 patients had GO, 11 of whom had it at diagnosis while 6 developed GO during treatment. During the study, 5 subjects were referred to radioiodine treatment, 3 to surgery. The remaining 22 subjects (GO n = 12, non-GO n = 10) completed the drug regimen. RESULTS: At diagnosis, Tg levels in GO patients (n = 11) were higher (84, 30-555 µg/L, median, range) than in non-GO patients (n = 19) (38, 3.5-287 µg/L), p = 0.042. Adding the 6 subjects who developed eye symptoms during treatment to the GO group (n = 17), yielded p = 0.001 vs. non-GO (n = 13). TRAb tended to be higher, while TPOAb and TgAb tended to be lower in the GO group. For the 22 patients who completed the drug regimen, Tg levels were higher in GO (n = 12) vs. non-GO (n = 10), p = 0.004, whereas TRAb levels did not differ. CONCLUSION: The data may suggest that evaluation of thyroglobulin levels in GD could contribute to identify patients at increased risk of developing GO. Possibly, thyroidal release of Tg in GD reflects a disturbance that also impacts retroorbital tissues.

Altered Expression of CXCL13 and Its Chemokine Receptor CXCR5 on B Lymphocytes during Active Graves' Orbitopathy.

PURPOSE: To characterize the phenotypic abnormalities of peripheral B cells in patients with Graves' orbitopathy (GO) and explore the role of chemokine CXC ligand 13 and its receptor type 5 (CXCL13/CXCR5) in relation to B-cell homeostasis using specific neutralizing antibodies. METHODS: Adults with active GO (n = 22), inactive GO (n = 28), and healthy control subjects (n = 28) were included in the study. Peripheral B cells and B-cell subsets were quantified and analyzed for CXCR5 expression by flow cytometry. The serum CXCL13 concentration was measured by enzyme-linked immunosorbent assays. For chemotactic experiments, Transwell plates were used, and migrating B cells were further analyzed by flow cytometry. RESULTS: Compared to healthy subjects, patients with active GO had a significantly higher number of CD19+ B cells and the CD19+CD27+ memory B-cell subset (P = .041 and P = .019, respectively), whereas a marginal increase in the number of these cells was found in patients with inactive GO (P = .062 and P = .087, respectively). Serum CXCL13 levels were significantly higher in patients with active GO (86.9 ± 30.4 pg/mL) than in those with inactive GO (41.7 ± 18.1 pg/mL; P < .001) and in healthy subjects (36.2 ± 7.8 pg/mL; P < .001). The increased CXCL13 concentration was positively and significantly correlated with the clinical activity score (r = 0.757, P < .001). Finally, serum from patients with active GO exerted a stronger chemotactic activity towards B cells and the CD19+CD27+ memory B-cell subset. Blocking CXCL13 or CXCR5 with neutralizing antibodies reduced B-cell migration by a mean of 20%. CONCLUSIONS: Our data suggest that aberrant CXCL13/CXCR5 expression may contribute to the deficits in B-lymphocyte homeostasis observed in active GO.

Correlation between serum anti-TSH receptor autoantibodies (TRAbs) and the clinical feature of Graves' orbitopathy.

BACKGROUND: Graves' orbitopathy (GO) is the most common extrathyroidal manifestation of Graves' disease (GD). Several studies support the involvement of TSH receptor autoantibodies (TRAbs) in the pathogenesis of GO, and a correlation between GO features and TRAbs has been reported, but not confirmed by all studies. Thus, we conducted a cross-sectional investigation to determine whether there is a correlation between TRAbs and the clinical features of GO in an initial phase of the eye disease. METHODS: Ninety consecutive patients with untreated GO (67 women and 23 men, age 48.9 ± 12.6 years) were included. Patients who had received treatments other than anti-thyroid drugs for hyperthyroidism or lubricants for GO were excluded. All patients underwent an endocrinological and ophthalmological evaluation, the latter including exophthalmometry, measurement of eyelid width, clinical activity score (CAS), visual acuity, assessment of diplopia, and NOSPECS score. TRAb levels were measured by a third-generation competitive immunoassay. RESULTS: There was a statistically significant, direct correlation between serum TRAb levels and CAS by linear regression analysis (R = 0.278, P = 0.007). The correlation was confirmed by a multiple regression analysis (R = 0.285; P = 0.006) including age and FT3 levels, which also correlated with CAS. There were no relationships between TRAbs and exophthalmometry, eyelid aperture, degree of diplopia, visual acuity, and NOSPECS score. CONCLUSIONS: The levels of TRAb in subjects with a recent-onset, untreated GO are directly correlated with the clinical activity of the disease, confirming a possible role of these antibodies in the pathogenesis of GO.

Circulating Exosomes From Patients With Graves' Disease Induce an Inflammatory Immune Response.

Exosomes are extracellular vesicles that can participate in autoimmune diseases. The purpose of this study was to explore whether circulating exosomes are involved in Graves' disease (GD) pathogenesis. In this study, serum exosomes were extracted from 26 healthy controls (HC-EXO), 26 GD patients (GD-EXO), and 7 Graves' ophthalmopathy patients (GO-EXO). For each group, the total protein content was detected, and thyrotropin receptor, insulin-like growth factor 1 receptor (IGF-1R), heat shock protein 60 (HSP60), and cluster of differentiation (CD) 63 expression were analyzed by Western blotting (WB). Healthy volunteer-derived peripheral blood mononuclear cells (PBMCs) and HC-EXO or GD-EXO were cocultured for 24 h, and immunofluorescence was used to observe the locations of the exosomes and toll-like receptor (TLR) 2/3. CD11c+TLR2+ and CD11c+TLR3+ cell percentages were determined by flow cytometry. Myeloid differentiation factor 88 (MyD88), toll/interleukin (IL)-1 receptor domain-containing adaptor inducing interferon-ß (TRIF) and p-P65 expression were analyzed by WB. IL-6 and IL-1ß supernatant levels were detected using enzyme-linked immunosorbent assay. The results showed that the total protein concentration was similar among GD-EXO, GO-EXO, and HC-EXO. IGF-1R and HSP60 expression was significantly higher in GD-EXO and GO-EXO than in HC-EXO. After coculturing PBMCs with GD-EXO or HC-EXO for 24 h, GD-EXO could bind to TLR2/3. GD-EXO significantly increased CD11c+TLR2+ and CD11c+TLR3+ cell percentages; MyD88, TRIF, and p-P65 protein expression; and IL-6 and IL-1ß levels. In conclusion, we first demonstrated that GD-EXO and GO-EXO highly expressed IGF-1R and HSP60. GD-EXO may induce an inflammatory response through the TLR/NF-κB signaling pathway and be involved in the pathogenesis of GD.

The Effect of Immunosuppression on Selected Antioxidant Parameters in Patients with Graves' Disease with Active Thyroid-Associated Orbitopathy.

BACKGROUND AND STUDY AIMS: Thyroid-associated orbitopathy, the most common extrathyroidal manifestation of Graves' disease, is an autoimmune inflammation of orbital soft tissue. We report the study assessing the effect of immunosuppressive treatment with methylprednisolone on selected antioxidant parameters in patients with Graves' disease with active thyroid-associated orbitopathy. PATIENTS AND METHODS: Activity and serum levels of selected antioxidant parameters as well as lipid peroxidation products were determined in a group of 56 patients with active thyroid-associated orbitopathy at three time-points: at baseline, after the discontinuation of intravenous methylprednisolone treatment and at 3 months after the discontinuation of additional oral methylprednisolone treatment. A control group consisted of 20 healthy age- and sex-matched volunteers. RESULTS: We found an increased activity of superoxide dismutase and glutathione peroxidase and increased serum levels of uric acid, malondialdehyde and conjugated dienes, as well as a reduced activity of paraoxonase-1 and reduced serum vitamin C level in the study group at baseline. Systemic intravenous and oral methylprednisolone therapy led to normalization of activity and concentration of the most studied parameters. CONCLUSION: Results of our study confirmed that oxidative stress is one of the factors involved in the pathogenesis of thyroid-associated orbitopathy and the methyloprednisolone treatment is effective in reducing both clinical symptoms and oxidative stress in patients with this disease.

Unusual onset of thyroid associated orbitopathy during pregnancy: case report and review of literature.

BACKGROUND: Thyroid associated orbitopathy (TAO) is the most common extrathyroidal complication of Graves' disease. The disease course ranges from mild, where symptomatic therapy is sufficient, to severe, where high dose steroid administration or orbital decompression surgery is required. Women of their reproductive age are more likely to be affected. Although pregnancy is a state of enhanced immune tolerance, TAO may develop or worsen in 0.2-0.4% of pregnant women. CASE PRESENTATION: We present the case of a 19-year-old woman who has developed hyperthyroidism and progressive TAO during the second trimester of her third pregnancy, which has improved postpartum. The possible mechanisms and the importance of follow up in pregnancy is discussed. CONCLUSIONS: Expectant mothers with Graves' disease require follow up of eye signs throughout pregnancy, preferably in the setting of a thyroid-eye clinic.

A case report of thyroid-associated Orbitopathy with elevated TPO antibodies.

BACKGROUND: Thyroid associated orbitopathy (TAO) is defined as an immune mediated inflammatory process affecting the extraocular muscles, connective and adipose tissue of uncertain etiopathogenesis. TAO are classically described in Grave's disease (GD) however it may occur in euthyroid and hypothyroid patients. Those patients usually test positive for Thyroid Stimulating Hormone receptor antibodies (TRAb). For instance, only few cases of severe Hashimoto's thyroiditis (HT) associated orbitopathy with negative TRAb are reported to date. CASE PRESENTATION: Herewith we report a rare case of a middle-aged female who presented with bilateral progressive upper and lower palpebral edema and a unilateral marked proptosis associated with asthenia, headache and decrease in visual acuity. Biological investigation was notable for high levels of anti-thyroid peroxidase antibodies (Anti-TPO) in an otherwise euthyroid patient with negative TRAb. Orbital Magnetic resonance imaging revealed edema of the extraocular muscles and inflammation of periorbital soft tissue. The patient received a treatment with intravenous methylprednisolone followed by oral treatment with prednisone. This regimen was both effective and safe with minimal metabolic side effects in our patient. CONCLUSION: Minor ocular manifestations of HT are common; however, severe sight threatening ophtalmopathy in the absence of TRAb is rare. Multiple differential diagnosis should be considered and investigated before diagnosing this rare entity. Management of similar cases is currently based on reports and no clear guidelines have been elaborated, corticosteroids is the mainstream of treatment with a potential benefit of selenium supplementation in mild to moderate cases.