CTLA4 polymorphisms and ophthalmopathy in Graves' disease patients: association study and meta-analysis

Endocrine adverse events related with immune checkpoint inhibitors: an update for clinicians

Designated as scientific breakthrough of current decade, immune checkpoint inhibitors attenuate the cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death 1 (PD-1)/ligand 1 (PD-L1) pathways, depriving cancer cells of a key strategy of evasion from immunosurveillance. The reinvigoration of immune response translates into clinical success, inevitably entwined with a novel constellation of immune-related adverse events. The present review dissects the endocrine immune-related adverse events, emphasizing their unique profile featured by unpredictable onset, irreversibility, nonspecific symptoms, wide clinical spectrum and sophisticated diagnostic work-up. Guidelines advocate individualized decision-making process guided by clinicians' judgement. Future perspective should be governed by five principles - prevention, anticipation, detection, treatment, monitoring - aiming to gain the optimal profit diminishing immunotoxicity.

A significant association of the CTLA4 gene variants with the risk of autoimmune Graves' disease in ethnic Kashmiri population

Graves' disease (GD) is the commonest cause of hyperthyroidism in populations with adequate iodine intake. It results from an abnormality in the immune system, which produces unique antibodies causing over production of thyroid hormones and glandular hyperplasia in individuals with genetic susceptibility. The Cytotoxic Lymphocyte Associated Antigen-4 (CTLA4) gene product serves the important function of immunomodulation, thereby helping in maintenance of peripheral self-tolerance. Studies on the association of the CTLA4 SNPs with GD have shown variations in the results from different populations. Since no such study has been carried out in ethnic Kashmiri population, we aimed to study a possible association of the CTLA4 SNPs (+49 A/G, -318C/T, CT 60 A/G and -1661 A/G) with GD. A total of 285 individuals (135 patients with GD and 150 healthy individuals) were genotyped using PCR-RFLP method and the results showed statistically significant differences in genotypic and allelic frequencies of cases and controls for + 49 A/G SNP (p=<0.001; OR = 5.14; CI = 2.17-12.19) and CT 60 A/G SNP (p = < 0.001; OR = 6.9; CI = 2.8-16.6), while -318C/T and -1661 A/G SNPs showed no significant association. We also studied the mRNA expression of the CTLA4 in patients with GD and healthy individuals by Real-Time PCR and found a decreased expression of the CTLA4 mRNA in PBMCs of patients with GD as compared to healthy controls with a -3.71-fold change. We conclude that the CTLA4 + 49 A/G and CT 60 A/G SNPs have a significant association with the risk of GD development in Kashmiri population and CTLA4 mRNA expression is significantly decreased in GD.

Tyrosine kinase inhibitors and immune checkpoint inhibitors-induced thyroid disorders

Recently, tyrosine kinase inhibitors (TKI) and immune checkpoint inhibitors (ICPIs) have emerged as new classes of anticancer therapies. Although generally considered less toxic than cytotoxic chemotherapy, these new drugs can cause significant unanticipated side effects including thyroid dysfunction. This review provides a literature assessment of thyroid dysfunctions induced by TKI and ICPIs. We intend to define for these two classes the frequency of thyroid involvement, the potential mechanisms that result in this toxicity, the clinical-biological impact and the therapeutic management. Detection of thyroid dysfunction requires monitoring of TSH, in combination with free T4 if needed and, depending on the clinical impact and the kinetics of biological abnormalities, starting symptomatic treatment of hyperthyroidism and/or correcting hypothyroidism.

IRF7 Gene Variations Confer Susceptibility to Autoimmune Thyroid Diseases and Graves' Ophthalmopathy

The objective of this study was to investigate whether IRF7 polymorphisms are associated with autoimmune thyroid diseases (AITDs). We selected three single nucleotide polymorphisms (SNPs) of IRF7, namely, rs1061501, rs1131665, and rs1061502 for genotyping using PCR-based ligase detection reaction (LDR) method in a total of 1659 participants (592 with Graves' disease, 297 with Hashimoto's thyroiditis, and 770 healthy controls). Gene-disease and genotype-clinical phenotype associations were evaluated for the three SNPs. Our results showed that the AG genotype and the minor allele G frequency of rs1131665 and rs1061502 in AITD patients were both higher than those of the controls (rs1131665: AG genotype: P = 0.017, OR = 1.968; allele G: P = 0.018, OR = 1.946; rs1061502: AG genotype: P = 0.029, OR = 1.866; allele G: P = 0.031, OR = 1.847). Subgroup analysis also showed that the AG genotype and the minor allele G frequency of rs1131665 and rs1061502 in Graves' disease patients were both higher than those of the controls (rs1131665: AG genotype: P = 0.015, OR = 2.074; allele G: P = 0.016, OR = 2.048; rs1061502: AG genotype: P = 0.034, OR = 1.919; allele G: P = 0.035, OR = 1.898). Furthermore, the allele G frequency of rs1061501 was associated with Graves' ophthalmopathy (P = 0.035, OR = 1.396). No significant difference in IRF7 polymorphisms was found between Hashimoto's thyroiditis patients and controls. Our study has revealed for the first time that IRF7 is a susceptibility gene for AITD, especially for Graves' disease and Graves' ophthalmopathy.

Association between polymorphic markers in candidate genes and the risk of manifestationof endocrine ophthalmopathy in patients with Graves’ disease

Aim. To analyze the association between the polymorphic markers in CTLA4, TNF, IL10 and IL16 genes and the risk of manifestation of endocrine ophthalmopathy (EO) in patients with Graves’ disease (GD). Materials and methods. Case-control study included 248 patients with GD. Using polymerase chain reaction we studied the distribution of alleles and genotypes of polymorphic markers such as A60G (rs3087243) in CTLA4 gene, G(-308)A (rs1800629) in TNF gene, G(-1082)A (rs1800896) in IL10 gene, T3249C (rs4778641) in IL16 gene among 141 patients with Graves’ disease and EO and 107 patients with GD without EO. Results and discussion. The frequencies of A alleles and the AA genotypes were significantly increased and the frequencies of G alleles and the GG genotype polymorphic markers rs3087243 of CTLA4 gene and rs1800896 of IL10 gene, as well as the GG genotype polymorphic marker rs1800629 of TNF gene were reduced in patients with GD and EO. The polymorphism in CTLA4 gene was also associated with the activity and the severity of EO. The comparative analysis of the allele and genotype frequency distribution of polymorphic markers of IL16 gene did not show the significant difference. Conclusion. The risk of manifestation and the development of EO in patients with Graves’ disease can be caused by not only environmental, but also genetic risk factors.

Long-term adverse event: inflammatory orbitopathy induced by pembrolizumab in a patient with metastatic melanoma

The recent advent of immune checkpoint inhibitors (ICI), including anti-programmed cell death 1 protein (anti-PD-1) agents has revolutionized the therapeutic approach of metastatic malignancies. Yet, ICI can disrupt immune tolerance resulting in enhanced immune activation in normal tissues with significant toxicity. A dysregulated activation of T-cells directed to normal tissues stands as the main mechanism of immune-related adverse events (irAE). To date, only two cases of immune-related inflammatory orbitopathy related to anti-PD-1 agents have been reported. This rare immune adverse event usually occurred early after ICI initiation. Here, we report the first case of late inflammatory orbitopathy occurring in a melanoma patient treated with pembrolizumab. Consequently, the occurrence of irAE under ICI should be monitored, even late after treatment instauration.

Association between rs3087243 and rs231775 polymorphism within the cytotoxic T-lymphocyte antigen 4 gene and Graves' disease: a case/control study combined with meta-analyses

We conducted a case/control study to assess the impact of SNP rs3087243 and rs231775 within the CTLA4 gene, on the susceptibility to Graves' disease (GD) in a Chinese Han dataset (271 cases and 298 controls). The frequency of G allele for rs3087243 and rs231775 was observed to be significantly higher in subjects with GD than in control subjects (p = 0.005 and p = 0.000, respectively). After logistic regression analysis, a significant association was detected between SNP rs3087243 and GD in the additive and recessive models. Similarly, association for the SNP rs231775 could also be detected in the additive model, dominant model and recessive model. A meta-analysis, including 27 published datasets along with the current dataset, was performed to further confirm the association. Consistent with our case/control results, rs3087243 and rs231775 showed a significant association with GD in all genetic models. Of note, ethnic stratification revealed that these two SNPs were associated with susceptibility to GD in populations of both Asian and European descent. In conclusion, our data support that the rs3087243 and rs231775 polymorphisms within the CTLA4 gene confer genetic susceptibility to GD.

Cancer immunotherapy - immune checkpoint blockade and associated endocrinopathies

Advances in cancer therapy in the past few years include the development of medications that modulate immune checkpoint proteins. Cytotoxic T-lymphocyte antigen 4 (CTLA4) and programmed cell death protein 1 (PD1) are two co-inhibitory receptors that are expressed on activated T cells against which therapeutic blocking antibodies have reached routine clinical use. Immune checkpoint blockade can induce inflammatory adverse effects, termed immune-related adverse events (IRAEs), which resemble autoimmune disease. In this Review, we describe the current data regarding immune-related endocrinopathies, including hypophysitis, thyroid dysfunction and diabetes mellitus. We discuss the clinical management of these endocrinopathies within the context of our current understanding of the mechanisms of IRAEs.

Association of CTLA-4 gene polymorphisms -318C/T and +49A/G and Hashimoto's thyroidits in Zahedan, Iran

Hashimoto's thyroiditis (HT) is a chronic inflammation of the thyroid gland and is known as the most common autoimmune disease. Development of autoimmune destruction of thyroid cells is a multi-step process involving convergence of genetic and environmental factors. Cytotoxic T-lymphocyte antigen-4 (CTLA-4) has an important role in homeostasis and negative regulation of immune responses, and is therefore considered to be a key element in the development of autoimmune diseases. The present study evaluated the association of the CTLA-4 gene polymorphisms 318C/T (rs5742909) and +49A/G (rs231775) with HT in an Iranian population (including 82 patients with HT and 104 healthy controls who were referred for routine premarital blood screenings). Genotyping was performed using the tetra-primer amplification refractory mutation system polymerase chain reaction technique. No significant differences were observed in genotype and allele frequencies in the single nucleotide polymorphisms (SNPs) between cases and controls. In the cases as well as in the controls, the TT genotype in the -318C/T polymorphism was absent and the predominant genotype was CC, while the predominant genotype for the +49A/G SNP was AA. As only few studies in this field have assessed Iranian and even Middle Eastern populations, additional studies with a higher number of samples are recommended to further assess the impact of -318C/T (rs5742909) and +49A/G (rs231775) polymorphisms of CTLA-4 on HT.

Association of Cytotoxic T-Lymphocyte-Associated Protein 4 (CTLA4) Gene Polymorphisms with Autoimmune Thyroid Disease in Children and Adults: Case-Control Study

Autoimmune thyroid disease (AITD), including Graves disease (GD) and Hashimoto disease (HD), is an organ-specific autoimmune disease with a strong genetic component. Although the cytotoxic T-lymphocyte-associated protein 4 (CTLA4) polymorphism has been reported to be associated with AITD in adults, few studies have focused on children. The aim of our study was to investigate whether the CTLA4 polymorphisms, including -318C/T (rs5742909), +49A/G (rs231775), and CT60 (rs3087243), were associated with GD and HD in Han Chinese adults and children. We studied 289 adult GD, 265 pediatric GD, 229 pediatric HD patients, and 1058 healthy controls and then compared genotype, allele, carrier, and haplotype frequencies between patients and controls. We found that CTLA4 SNPs +49A/G and CT60 were associated with GD in adults and children. Allele G of +49A/G was significantly associated with GD in adults (odds ratio [OR], 1.50; 95% confidence interval [CI], 1.21–1.84; corrected P value [Pc] < 0.001) and children (OR, 1.42; 95% CI, 1.15–1.77; Pc = 0.002). Allele G of CT60 also significantly increased risk of GD in adults (OR, 1.63; 95% CI, 1.27–2.09; Pc < 0.001) and GD in children (OR, 1.58; 95% CI, 1.22–2.04; Pc < 0.001). Significant linkage disequilibrium was found between +49A/G and CT60 in GD and control subjects (D’ = 0.92). Our results showed that CTLA4 was associated with both GD and HD and played an equivalent role in both adult and pediatric GD in Han Chinese population.

[Association of CTLA4 and TNF gene polymorphisms with endocrine ophthalmopathy in ethnic Russian patients with Graves' disease]

AIM

To analyze the associations of the rs3087243 CTLA4 polymorphism and the rs1800629 TNF polymorphism with endocrine ophthalmopathy (EOP) in ethnic Russian patients with Graves' disease (GD).

MATERIAL AND METHODS

The case-control study enrolled 205 patients with GD. The distribution of alleles and genotypes of the rs3087243 CTLA4 and rs1800629 TNF polymorphisms was studied in 141 patients with GD and EOP (a GD+EOP group) and 64 patients with GD without EOP (a GD-EOP group). The polymorphic alleles were identified by polymerase chain reaction-restriction fragment length analysis.

RESULTS

The patients with GD in their history and EOP had significantly higher frequencies of A allele and AA genotype and a lower proportion of G allele and GG genotype of the rs3087243 CTLA4 polymorphism. Comparative analysis revealed no significant differences in the frequency of the alleles and genotypes of the rs1800629 TNF polymorphism.

CONCLUSION

The rs3087243 CTLA4 polymorphism is associated with the risk of EOP in ethnic Russian patients with GD.

Thyroid-like ophthalmopathy in a euthyroid patient receiving Ipilimumab

A 68-year-old lady with metastatic malignant melanoma was treated with Ipilimumab. She presented to Eye Casualty unable to move her eyes. Physical examination confirmed ophthalmoplegia and identified proptosis bilaterally. Radiological imaging showed bilateral enlargement of all the extra-ocular muscles suggestive of thyroid eye disease. Laboratory investigations found this patient to be euthyroid. A diagnosis of thyroid-like orbitopathy secondary to Ipilimumab therapy was made. Thyroid function tests should be performed for all patients prior to their commencement of Ipilimumab. Thyroid-like eye disease may develop in patients treated with Ipilimumab even if they remain euthyroid.

Associations of CTLA4 Gene Polymorphisms with Graves' Ophthalmopathy: A Meta-Analysis

Many studies have established that T-lymphocyte antigen-4 (CTLA4) is a susceptible gene for Graves' disease (GD). Also many studies showed the association between the CTLA4 exon-1 49A/G polymorphism and the risk of developing Graves' ophthalmopathy (GO) in GD patients. But those results were inconsistent. In recent years many new studies were published which helped to shed light on the relationship of CTLA4 SNP49 with GO. So we performed the meta-analysis to explore the association between the SNP49 and GO susceptibility in GD patients. Studies up to February 29, 2012, were searched by using PubMed. The odds ratio was used to evaluate the strength of the association. Altogether 12 case-control studies involving 2,505 participants were included in the meta-analysis. Results showed that the G allele was related to the increased risk of GO compared with the A allele under allelic genetic model (OR = 1.14, 95% CI: 1.14–1.72, P = 0.001) in European subgroup. No publication bias was detected. Our results showed that the SNP49 polymorphism of CTLA4 gene was related to increased risk of GO.

CTLA-4 CT60 (rs3087243) polymorphism and autoimmune thyroid diseases susceptibility: a comprehensive meta-analysis

OBJECTIVE

To determine whether the cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) CT60 polymorphism (rs3087243) confers susceptibility to autoimmune thyroid disease (AITDs).

METHODS

A meta-analysis was performed using: (1) allelic contrast, (2) recessive model and (3) dominant model. Electronic search of PubMed, Medline and Chinese National Knowledge Infrastructure (CNKI) was conducted to select studies.

RESULTS

Finally, a total of 20 separate studies were available for the current meta-analysis: Graves' disease (GD): 18 studies including 1 Iranian, 6 Caucasian and 11 Asian populations; Hashimoto's thyroiditis (HT): seven studies including one Iranian, three Caucasian and three Asian populations. A significant association was found between the CTLA-4 CT60 polymorphism (rs3087243) and GD, with regard to comparisons between allele and genotype frequencies (all p < 0.001). After stratification by ethnicity, significant relationships were consistently identified both in Caucasian and Asian populations. Furthermore, the association between this allelic variant and HT risk was also found in overall and Asian populations (OR: 1.26, 95% CI: 1.10-1.44; OR: 1.45, 95% CI: 1.19-1.76, respectively).

CONCLUSION

Taken together, our study suggested that the CT60 polymorphism (rs3087243) in CTLA-4 gene might confer susceptibility to the AITDs (GD/HT).

Delineating the autoimmune mechanisms in Graves' disease

The immunologic processes involved in autoimmune thyroid disease (AITD), particularly Graves' disease (GD), are similar to other autoimmune diseases with the emphasis on the antibodies as the most unique aspect. These characteristics include a lymphocytic infiltrate at the target organs, the presence of antigen-reactive T and B cells and antibodies, and the establishment of animal models of GD by antibody transfer or immunization with antigen. Similar to other autoimmune diseases, risk factors for GD include the presence of multiple susceptibility genes, including certain HLA alleles, and the TSHR gene itself. In addition, a variety of known risk factors and precipitators have been characterized including the influence of sex and sex hormones, pregnancy, stress, infection, iodine and other potential environmental factors. The pathogenesis of GD is likely the result of a breakdown in the tolerance mechanisms, both at central and peripheral levels. Different subsets of T and B cells together with their regulatory populations play important roles in the propagation and maintenance of the disease process. Understanding different mechanistic in the complex system biology interplay will help to identify unique factors contributing to the AITD pathogenesis.

Graves' ophthalmopathy: a review of immunogenetics

Graves’ disease (GD) is the most common cause of thyrotoxicosis and often involves the orbits. Graves’ ophthalmopathy (GO), also known as Thyroid Eye Disease (TED), can be clinically significant and advance to sight-threatening stages. Our knowledge of the immunogenetic pathophysiology of GO is rapidly expanding. The present review is an attempt to summarize the current state of knowledge on the immunogenetics of GO. First we briefly review the epidemiology and clinical importance of GO, and then we describe in detail the macromolecular pathogenesis and finally immunogenetics of GO. Discrepancies between the results from various reports and the limitations of the available data are discussed. In particular, there is a scarcity of data from non-Asian populations. While several studies have demonstrated significant associations between polymorphisms in certain genes (especially CTLA-4, HLA-DRB-1, and TNF-α), there is a need for studies that investigate the relationship between polymorphisms and both serum and local concentrations of the resulting proteins. A complete understanding of GO susceptibility and pathogenesis has not been yet possible due to a number of important knowledge gaps that need to be filled by future research.

Ethnic differences in the clinical presentation of Graves' ophthalmopathy

Ethnic differences in a number of eye conditions have been described. The literature on ethnic differences in Graves' ophthalmopathy (GO) is limited. There is some evidence to suggest Asian patients with GO may manifest milder phenotypic features of GO, with less proptosis and evidence of extraocular muscle involvement and restriction. The reasons for these differences are likely to be multifactorial and include orbital and lid anatomy, genetic background and autoimmune responses including TSH -receptor antibodies. These differences should be kept in mind when evaluating and managing patients with GO.

The pathophysiology of thyroid eye disease: implications for immunotherapy

PURPOSE OF REVIEW

Thyroid eye disease (TED) is a poorly understood autoimmune manifestation most commonly associated with Graves' disease. Current nonspecific treatment paradigms offer symptomatic improvement but fail to target the underlying pathogenic mechanisms, and thus do not significantly alter the long-term disease outcome. The purpose of this review is to provide an update of the current understanding of the immunopathogenesis of TED and explore these mechanisms for targeted immunotherapy.

RECENT FINDINGS

Orbital fibroblasts are integral to the pathogenesis of TED and may modulate immune responses by production of cytokines and hyaluronan in response to activation of shared autoantigens including thyrotropin receptor and insulin-like growth factor-1 receptor. Bone marrow-derived fibrocytes share many of these phenotypic and functional features, suggesting a link between systemic and site-specific disease. Use of targeted immunotherapies in TED is limited, though data from the use Rituximab (RTX), a B-cell depleting agent, are encouraging. Sustained clinical response has been seen with RTX in several reports, despite return of peripheral B-cell levels to pretreatment levels. Additionally, this response appears to be independent of cytokine and antibody production, suggesting modulation of antigen presentation as a mechanism of its effect.

SUMMARY

Progressive advances in the understanding of the immunopathogenesis of TED continue to spur clinical trials utilizing targeted immune therapies. Continued understanding of the molecular mechanisms of disease will expand potential treatments for TED patients and obviate the need for reconstructive surgical therapies.

CTLA4 exon1 A49G polymorphism in Slovak patients with rheumatoid arthritis and Hashimoto thyroiditis-results and the review of the literature

Autoimmune thyroid diseases frequently overlaps with rheumatoid arthritis (RA). Among genetic factors, the role of the HLA antigens and CTLA4 gene polymorphisms in the overlapping has been suggested. The aim of this study was to investigate the alleles and genotypes frequency of the CTLA4 exon1 A49G polymorphism in Slovak patients with RA, Hashimoto thyroiditis (HT), both (RA + HT) and in healthy controls. Fifty-seven unrelated adults with RA, 57 patients with HT, 34 patients with both (RA + HT), and 51 normal subjects were studied. All were ethnic Slovaks living in the same geographical area. The CTLA4 exon1 A49G polymorphism was genotyped by using small amplicon melting analysis after real-time PCR. The CTLA4 49GG genotype and G allele frequency in the group with RA was not significantly higher in comparison with controls (10.53% vs. 9.8%, p = 0.62, OR 1.39, 95% CI 0.35-5.74 and 39.47% vs. 34.31%, p = 0.43, OR 1.25, 95% CI 0.72-2.18). The frequency of GG genotype was slightly but not significantly higher in patients with HT as compared with control group (19.3% vs. 9.8%, p = 0.17, OR 2.27, 95% CI 0.67-8.45). However, the frequency of GG genotype and G allele in patients with both RA and HT was significantly higher than that in controls (29.41% vs. 9.8%, p = 0.02, OR 4.49, 95% CI 1.20-18.54 and 51.47% vs. 34.31%, p = 0.03, OR 2.02, 95% CI 1.08-3.81). The frequency of GG genotype of CTLA4 A49G gene polymorphism in Slovak patients with RA is not significantly higher in comparison to control group. However, carriers of GG genotype with RA may be susceptible to develop HT.

Thyroid autoimmunity and ophthalmopathy related to melanoma biological therapy

OBJECTIVE

Ipilimumab is a fully human MAB against cytotoxic T-lymphocyte antigen 4 (CTLA4). CTLA4 negatively regulates immune cell activation. In patients with metastatic melanoma, ipilimumab increases survival time and induces complete remission in some patients. However, immune-related adverse events including endocrinopathies have been reported. Bevacizumab, an angiogenesis inhibitor, has been used in combination with ipilimumab in patients with advanced melanoma.

PATIENTS AND METHODS

In this study, we report three patients who received ipilimumab alone or combined with bevacizumab therapy and developed thyroiditis, and the first report of euthyroid Graves' ophthalmopathy.

RESULTS

Case 1 is a 51-year-old female who presented with severe eye pain, proptosis, and periorbital edema. Laboratory results revealed normal TSH, elevated thyroid antibodies but low titer of anti-TSH receptor antibody. Imaging was consistent with Graves' ophthalmopathy. Cases 2 and 3 were referred for hyperthyroidism, and workup revealed thyroiditis. These three cases suggest that patients with advanced melanoma treated with ipilimumab +/- bevacizumab may be susceptible to a variety of thyroid disorders.

CONCLUSIONS

Anti-CTLA4 therapy has shown promising results in treating advanced malignancy such as melanoma and renal carcinoma. A number of endocrinopathies, including thyroid disorders, may develop during ipilimumab therapy. The association of bevacizumab with endocrinopathies is not clear, although a few reports suggest a link to hypothyroidism. All patients on ipilimumab and/or bevacizumab therapy should be monitored for signs or symptoms of thyroiditis.

Immunopathogenesis of thyroid eye disease: emerging paradigms

Graves disease represents a systemic autoimmune process targeting the thyroid, orbit, and pretibial skin. The thyroid dysfunction is treatable, but no consistently effective medical therapy has yet been described for the orbital manifestations of Graves disease, also known as thyroid-associated ophthalmopathy or thyroid eye disease. Several autoantigens are potentially relevant to the pathogenesis of thyroid eye disease. Activating antibodies generated against the thyrotropin receptor can be detected in a majority of patients, and these drive hyperthyroidism. However, stimulating antibodies against the insulin-like growth factor-1 receptor (IGF-1R) may also play a role in the extra-thyroid manifestations of Graves disease. IGF-1R is overexpressed by orbital fibroblasts derived from patients with thyroid eye disease, whereas IGF-1R(+) T and IGF-1R(+) B cells are considerably more frequent in Graves disease. Actions of several cytokines and the molecular interplay peculiar to the orbit appear to provoke the inflammation, fat expansion, and deposition of excessive extracellular matrix molecules in thyroid eye disease. Based upon these new insights, several therapeutic strategies can now be proposed that, for the first time, might specifically interrupt its pathogenesis.

Gatekeepers of intestinal inflammation

The intestine is subjected to a barrage of insults from food, bacterial flora, and pathogens. Despite this constant antigenic challenge, the mucosal tissues lining the intestinal tract remain largely under control. The mechanisms regulating the homeostatic balance in the gut have been investigated for many years by many groups, but the precise nature of the regulatory control remains elusive. In this review, we provide an overview of pathways proposed to be involved in dampening the inflammatory response and maintaining the homeostatic balance in the intestine, and how these pathways may be disrupted in ulcerative colitis and Crohn's disease.

The association of interleukin-1alpha and interleukin-1beta polymorphisms with the risk of Graves' disease in a case-control study and meta-analysis

The proinflammatory cytokine interleukin (IL)-1 family has a central role in mediating inflammation and joint destruction in Graves' disease (GD). A number of studies, investigating rs1800587 (IL-1alpha, T-889 C) and rs16944 (IL-1beta, A-511 G) polymorphisms to test their possible association with GD and Graves' ophthalmopathy (GO), had inconsistent results. Our study aims to further evaluate the possible association of these two polymorphisms with GD and GO within the Han Chinese population using a case-control association study as well as a meta-analysis covering three previous studies from Taiwan, Iran, and Poland. Based on 760 Chinese GD patients, including 190 of GO cases among them, and 735 healthy control subjects, our data showed that the genotype or allele distributions of rs1800587 and rs16944 polymorphisms were significantly associated with GD (p = 0.003-0.049) and more so with GO (p = 0.001-0.021). The meta-analysis showed the risk-increasing effects for the TC and TT genotypes of rs1800587 in GD (odds ratio [OR] = 2.07, p = 0.03) and GO (OR = 3.22, p = 0.04), and a protective effect for the AA genotype of rs16944 in GD (OR = 0.70, p = 0.002) and GO (OR = 0.65, p = 0.02). The results confirmed that the rs1800587 (IL-alpha, T-889 C) and rs16944 (IL-1beta, A-511 G) polymorphisms may confer susceptibility to GD and GO in Asian population.

Association of CTLA-4 gene polymorphism with Graves' disease and ophthalmopathy in Iranian patients

BACKGROUND

The cytotoxic T lymphocyte associated antigen-4 (CTLA-4) gene, is one of the candidate genes for susceptibility to Graves' disease. This study aimed to investigate the association of Graves' disease and Graves' ophthalmopathy with polymorphisms at position +49 in exon 1 and positions -318 and -1147 in the promoter region of CTLA-4 gene in Iranian patients.

METHODS

A total of 205 unrelated Iranian patients with Graves' disease who were referred to the outpatient endocrine clinic of a large university general hospital and 103 sex-matched healthy controls were included in this study. Venous blood was obtained, genomic DNA was extracted by a salting out method, and the polymorphisms at positions +49, -318 and -1147 of the CTLA-4 gene were determined using the PCR-restriction fragment length polymorphism method (PCR-RFLP). Genotype and allele frequencies were determined.

RESULTS

The frequency of the G allele at position +49 was significantly higher in patients with Graves' disease than in the control group (27.1% vs. 15.1%, OR=2.096, 95%CI=1.350-3.253 and p<0.01). Significant trends were not seen for the other two polymorphisms studied. In patients with ophthalmopathy, the frequency of the G allele at position +49 was higher than in those without ophthalmopathy (33.8% vs. 20.0%, OR=2.043, 95%CI=1.304-3.202 and p<0.01).

CONCLUSION

The results of this study suggest that the G allele at position +49 in exon1 of the CTLA-4 gene is associated with Graves' disease and Graves' ophthalmopathy in Iranian patients.

[Susceptibility genetic variants in Hungarian morbus Crohn and ulcerative colitis patients]

We examined several susceptibility genetic variants to inflammatory bowel disease (Crohn's disease, ulcerative colitis) in Hungarian population, such as the CARD15 R702W, G908R, 1007finsC genetic variants, the SLC22A4 C1672T and SLC22A5 G-207C variants and their determined TC haplotype, the CTLA4 gene A+49G genetic variant and the rs10889677 C/A, rs2201841 T/C, rs1884444 G/T variants of the IL23R gene. We examined 201 adult patients with Crohn's disease, 241 adult patients with ulcerative colitis and 19 pediatric patients with Crohn's disease. For control 235 adult and 49 pediatric subjects were used. The genotyping was carried out using PCR/RFLP methods and direct sequencing. From the CARD15 gene mutations in the adult Crohn's disease population the 1007finsC, while in the pediatric population the 1007finsC and the G908R were significantly associated with an increased risk for Crohn's disease. We found no significant differences comparing the results of the patients and the controls by the SLC22A4, SLC22A5 genetic variants and the TC haplotype. The A+49G variant of the CTLA4 gene was not an independent determinant to inflammatory bowel disease. We found that the IL23R gene variants, rs10889677 C/A and rs2201841 T/C appear to increase susceptibility to Crohn's disease. It depends on the different populations whether this genetic variant means an obligatory risk factor to inflammatory bowel disease.

Recent insights into the pathogenesis and management of thyroid-associated ophthalmopathy

PURPOSE OF REVIEW

To identify and critique the most recent experimental findings regarding the pathogenesis and therapy of thyroid-associated ophthalmopathy.

RECENT FINDINGS

Much of the recent work in this field has focused on identifying genetic alterations associated with the phenotypes of Graves' disease and thyroid-associated ophthalmopathy and investigating their functional consequences. Identified candidate genes include CD40, cytotoxic T-lymphocyte antigen-4, protein tyrosine phosphatase-22, human leukocyte antigen-major histocompatibility complex and those associated with the X-chromosome. Efforts to generate a complete rodent model of Graves' disease continue with little progress. These uniformly involve the immunization of animals with the thyrotropin receptor. Studies conducted in vitro have focused on the actions of cytokines in orbital fibroblasts, the potential role of the insulin-like growth factor-1 receptor and activating antibodies directed against it as a fibroblast and T cell activation pathway. Reports continue to appear examining the potential relationship between the thyrotropin receptor and orbital adipogenesis. Regarding therapy for thyroid-associated ophthalmopathy, small molecules and antibodies disrupting cytokine pathways and lymphocyte function are currently under examination and have yielded promising albeit preliminary results.

SUMMARY

Thyroid-associated ophthalmopathy remains a vexing medical problem, the pathogenesis of which remains uncertain. A number of obstacles continue to plague major advances, not least of which is the absence of a robust animal model. A few new insights seem to represent departure from traditional thinking about this disease and may herald important innovation.

Susceptibility genes in Graves' ophthalmopathy: searching for a needle in a haystack?

The variety of clinical presentations of eye changes in patients with Graves' disease suggests that complex interactions between genetic, environmental, endogenous and local factors influence the development/severity of Graves' ophthalmopathy (GO). At present, the role of genetic factors in the development of GO remains unknown. Based on small case-control association studies with candidate genes, several susceptibility loci in GO have been proposed. These are human leucocyte antigen (HLA, 6p21.3), cytotoxic T-lymphocyte antigen-4 (CTLA-4, 2q33), tumour necrosis factor (TNF, 6p21.3), interferon-gamma (IFN-gamma, 12q14), intercellular adhesion molecule-1 (ICAM-1, 19p13), and thyroid stimulating hormone receptor gene (TSH-R, 14q31). Unfortunately, these results were either not confirmed or require replication in larger studies. There are many reasons for the lack of reproducibility of association studies in GO, including poor characterization of the studied groups and small sample sizes, which may result in both false positive and negative results. Thus, the genetic background of GO remains to be elucidated in future research. However, the possibility that GO may be a genetically heterogeneous disorder, or that the development of GO may be predominantly influenced by environmental factors such as cigarette smoking, can not be disregarded.

No association of the cytotoxic T-lymphocyte associated gene CTLA4 +49A/G polymorphisms with Crohn’s disease and ulcerative colitis in Hungarian population samples

AIM: The goal of the current work was to analyse the prevalence of the +49A/G variant of the cytotoxic T-lymphocyte antigen 4 gene (CTLA4) in Hungarian patients with Crohn’s disease (CD) and ulcerative colitis (UC).

METHODS: A total of 130 unrelated subjects with CD and 150 with UC, and 170 matched controls were genotyped for the single nucleotide polymorphism (SNP). The genotypes were determined by using PCR/RFLP test.

RESULTS: The G allele frequency and the prevalence of the GG genotype were 38.1% and 12.3% in the CD group, 40.6% and 18.6% in the UC patients, and 37.4% and 15.9% in the control group, respectively.

CONCLUSION: The results of the current study show that carriage of the +49G SNP in heterozygous or in homozygous form does not confer risk either for CD or for UC in the Hungarian population.