Interleukin (IL)-23 receptor is a major susceptibility gene for Graves' ophthalmopathy: the IL-23/T-helper 17 axis extends to thyroid autoimmunity

Associations between immune cell traits and autoimmune thyroid diseases: a bidirectional two-sample mendelian randomization study

Autoimmune thyroid diseases (AITDs), mainly including Graves' disease (GD) and Hashimoto's thyroiditis (HT), are common autoimmune disorders characterized by abnormal immune responses targeting the thyroid gland. We conducted a bidirectional two-sample MR analysis using the largest dataset of peripheral immune cell phenotypes from Sardinia, and the AITD dataset from the 10th round of the FinnGen and the UK Biobank project. Instrumental variables (IVs) were rigorously selected based on the three assumptions of MR and analyzed using the Wald ratio, inverse-variance weighted (IVW), MR-Egger, and weighted median methods. Additionally, sensitivity analyses were performed using Cochrane's Q, the Egger intercept, the MR-PRESSO, and the leave-one-out (LOO) method to ensure the robustness of the results. The Steiger test was utilized to identify and exclude potential reverse causation. The results showed that 3, 3, and 11 immune cell phenotypes were significantly associated with the risk of AITD. In GD, the proportion of naive CD4-CD8- (DN) T cells in T cells and the proportion of terminally differentiated CD4+T cells in T cells showed the strongest inducing and protective effects, respectively. In HT, lymphocyte count and CD45 on CD4+T cells showed the strongest inducing and protective effects, respectively. In autoimmune hypothyroidism, CD127 CD8+T cell count and terminally differentiated DN T cell count exhibited the strongest inducing and protective effects, respectively. Through MR analysis, our study provides direct genetic evidence of the impact of immune cell traits on AITD risk and lays the groundwork for potential therapeutic and diagnostic target discovery.

Identification of the grass carp interleukin-23 receptor and its proinflammatory role in intestinal inflammation

The interleukin 23 receptor (IL-23R) is associated with a variety of inflammatory diseases in humans and other mammals. However, whether IL-23R is involved in inflammatory diseases in teleost fish is less understood. Thus, to investigate the potential involvement of IL-23R in fish inflammatory diseases, the full-length cDNA of IL-23R from grass carp Ctenopharyngodon idella was cloned and used to generate a recombinant protein (rgcIL-23R) containing the extracellular domain of IL-23R, against which a polyclonal antibody (rgcIL-23R pAb) was then developed. qPCR analysis revealed that IL-23R mRNA was significantly upregulated in most grass carp tissues in response to infection with Gram-negative Aeromonas hydrophila. Treatment with rgcIL-23R significantly induced IL-17A/F1 expression in C. idella kidney (CIK) cells. By contrast, knockdown of IL-23R caused significant decreases in IL-23R, STAT3, and IL-17N expression in CIK cells after lipopolysaccharide (LPS) stimulation. Similarly, rgcIL-23R pAb treatment effectively inhibited the LPS-induced increase in the expression of IL-23 subunit genes and those of the IL-23/IL-17 pathway in CIK cells. Furthermore, intestinal symptoms identical to those caused by A. hydrophila were induced by anal intubation with rgcIL-23R, but suppressed by rgcIL-23R pAb. Therefore, these results suggest that IL-23R has a crucial role in the regulation of intestinal inflammation and, thus, is a promising target for controlling inflammatory diseases in farmed fish.

Identification of immune-related regulatory networks and diagnostic biomarkers in thyroid eye disease

BACKGROUND

Thyroid eye disease (TED) is an orbit-associated autoimmune inflammatory disorder intricately linked to immune dysregulation. Complete pathogenesis of TED remains elusive. This work aimed to mine pathogenesis of TED from immunological perspective and identify diagnostic genes.

METHODS

Gene expression microarray data for TED patients were downloaded from Gene Expression Omnibus, immune-related genes (IRGs) were from ImmPort database, and TED-related transcription factors (TFs) were from Cirtrome Cancer database. Differential analysis, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed. Regulatory networks of TFs and IRGs were constructed with Cytoscape. Diagnostic biomarkers in TED were identified through LASSO. Immune cell infiltration analysis was performed using CIBERSORT.

RESULTS

Twenty-three immune-related DEmRNAs were revealed and were primarily enriched in humoral immune response, positive regulation of inflammatory response, IL-17, and TNF pathways. Co-expression regulatory network included four TFs and 16 immune-related DEmRNAs. Seven diagnostic genes were identified, with Area Under the Curve (AUC) of 0.993 for training set and AUC value of 0.836 for validation set. TED patients exhibited elevated infiltration levels by macrophages M2, mast cells, and CD8 T cells among 22 immune cell types, whereas macrophages M2 and mast cells resting were significantly lower than normal group.

CONCLUSIONS

The seven feature genes had high diagnostic value for TED patients. Our work explored regulatory network and diagnostic biomarkers, laying theoretical basis for TED diagnosis and treatment.

Dysthyroid Optic Neuropathy

PURPOSE

Dysthyroid optic neuropathy (DON) is a sight-threatening complication of thyroid eye disease (TED). This review provides an overview of the epidemiology, pathogenesis, diagnosis, and current therapeutic options for DON.

METHODS

A literature review.

RESULTS

DON occurs in about 5% to 8% of TED patients. Compression of the optic nerve at the apex is the most widely accepted pathogenic mechanism. Excessive stretching of the nerve might play a role in a minority of cases. Increasing age, male gender, smoking, and diabetes mellitus have been identified as risk factors. Diagnosis of DON is based on a combination of ≥2 clinical findings, including decreased visual acuity, decreased color vision, relative afferent pupillary defect, visual field defects, or optic disc edema. Orbital imaging supports the diagnosis by confirming apical crowding or optic nerve stretching. DON should be promptly treated with high-dose intravenous glucocorticoids. Decompression surgery should be performed, but the response is incomplete. Radiotherapy might play a role in the prevention of DON development and may delay or avoid the need for surgery. The advent of new biologic-targeted agents provides an exciting new array of therapeutic options, though more research is needed to clarify the role of these medications in the management of DON.

CONCLUSIONS

Even with appropriate management, DON can result in irreversible loss of visual function. Prompt diagnosis and management are pivotal and require a multidisciplinary approach. Methylprednisolone infusions still represent first-line therapy, and surgical decompression is performed in cases of treatment failure. Biologics may play a role in the future.

The IL-17 family in diseases: from bench to bedside

The interleukin-17 (IL-17) family comprises six members (IL-17A-17F), and recently, all of its related receptors have been discovered. IL-17 was first discovered approximately 30 years ago. Members of this family have various biological functions, including driving an inflammatory cascade during infections and autoimmune diseases, as well as boosting protective immunity against various pathogens. IL-17 is a highly versatile proinflammatory cytokine necessary for vital processes including host immune defenses, tissue repair, inflammatory disease pathogenesis, and cancer progression. However, how IL-17 performs these functions remains controversial. The multifunctional properties of IL-17 have attracted research interest, and emerging data have gradually improved our understanding of the IL-17 signaling pathway. However, a comprehensive review is required to understand its role in both host defense functions and pathogenesis in the body. This review can aid researchers in better understanding the mechanisms underlying IL-17's roles in vivo and provide a theoretical basis for future studies aiming to regulate IL-17 expression and function. This review discusses recent progress in understanding the IL-17 signaling pathway and its physiological roles. In addition, we present the mechanism underlying IL-17's role in various pathologies, particularly, in IL-17-induced systemic lupus erythematosus and IL-17-related tumor cell transformation and metastasis. In addition, we have briefly discussed promising developments in the diagnosis and treatment of autoimmune diseases and tumors.

Roles of four targets in the pathogenesis of graves' orbitopathy

Graves' orbitopathy (GO) is an autoimmune disease that involves complex immune systems. The mainstays of clinical management for this disease are surgery, targeted drugs therapy, and no-targeted drugs drug therapy. targeted drugs can improve therapeutic efficacy and enhance the quality of life for GO patients. However, as a second-line treatment for GO, targeted drugs such as tocilizumab and rituximab have very limited therapeutic effects and may be accompanied by side effects. The introduction of Teprotumumab, which targets IGF-IR, has made significant progress in the clinical management of GO. The pathophysiology of GO still remains uncertain as it involves a variety of immune cells and fibroblast interactions as well as immune responses to relevant disease targets of action. Therfore, learning more about immune response feedback pathways and potential targets of action will assist in the treatment of GO. In this discussion, we explore the pathogenesis of GO and relevant work, and highlight four potential targets for GO: Interleukin-23 receptor (IL-23 R), Leptin receptor (LepR), Orbital fibroblast activating factors, and Plasminogen activator inhibitor-1 (PAI-1). A deeper understanding of the pathogenesis of GO and the role of potential target signaling pathways is crucial for effective treatment of this disease.

Lipid metabolism in Th17 cell function

Among the subset of T helper cells, Th17 cells are known to play a crucial role in the pathogenesis of various autoimmune disorders, such as psoriasis, rheumatoid arthritis, inflammatory bowel disease, steroid-resistant asthma, and multiple sclerosis. The master transcription factor retinoid-related orphan receptor gamma t (RORγt), a nuclear hormone receptor, plays a vital role in inducing Th17-cell differentiation. Recent findings suggest that metabolic control is critical for Th17-cell differentiation, particularly through the engagement of de novo lipid biosynthesis. Inhibition of lipid biosynthesis, either through the use of pharmacological inhibitors or by the deficiency of related enzymes in CD4⁺ T cells, results in significant suppression of Th17-cell differentiation. Mechanistic studies indicate that metabolic fluxes through both the fatty acid and cholesterol biosynthetic pathways are essential for controlling RORγt activity through the generation of a lipid ligand of RORγt. This review highlights recent findings that underscore the significant role of lipid metabolism in the differentiation and function of Th17 cells, as well as elucidating the distinctive molecular pathways that drive the activation of RORγt by cellular lipid metabolism. We further elaborate on a pioneering therapeutic approach for ameliorating autoimmune disorders via the inhibition of RORγt.

2021 update on thyroid-associated ophthalmopathy

PURPOSE

Our understanding of thyroid-associated ophthalmopathy (TAO, A.K.A Graves' orbitopathy, thyroid eye disease) has advanced substantially, since one of us (TJS) wrote the 2010 update on TAO, appearing in this journal.

METHODS

PubMed was searched for relevant articles.

RESULTS

Recent insights have resulted from important studies conducted by many different laboratory groups around the World. A clearer understanding of autoimmune diseases in general and TAO specifically emerged from the use of improved research methodologies. Several key concepts have matured over the past decade. Among them, those arising from the refinement of mouse models of TAO, early stage investigation into restoring immune tolerance in Graves' disease, and a hard-won acknowledgement that the insulin-like growth factor-I receptor (IGF-IR) might play a critical role in the development of TAO, stand out as important. The therapeutic inhibition of IGF-IR has blossomed into an effective and safe medical treatment. Teprotumumab, a β-arrestin biased agonist monoclonal antibody inhibitor of IGF-IR has been studied in two multicenter, double-masked, placebo-controlled clinical trials demonstrated both effectiveness and a promising safety profile in moderate-to-severe, active TAO. Those studies led to the approval by the US FDA of teprotumumab, currently marketed as Tepezza for TAO. We have also learned far more about the putative role that CD34+ fibrocytes and their derivatives, CD34+ orbital fibroblasts, play in TAO.

CONCLUSION

The past decade has been filled with substantial scientific advances that should provide the necessary springboard for continually accelerating discovery over the next 10 years and beyond.

Clinical relevance of estimating circulating interleukin-17 and interleukin-23 during methylprednisolone therapy in Graves' orbitopathy: A preliminary study

PURPOSE

Graves' orbitopathy (GO) is an important problem in endocrinology. Currently used methods of assessing the degree of activity of the autoimmune process are not satisfactory. Therefore, there is a need to establish indicators of greater utility.

PATIENTS AND METHODS

The study included 35 patients: 15 with GO, 10 with Graves' disease (GD) without GO and 10 controls. Patients with GO received methylprednisolone (MP) for 12 weeks. Concentrations of thyrotropin receptor antibodies (TSHRab), interleukin 17 (IL-17) and 23 (IL-23) were obtained before administering the first dose of MP, after 6 and 12 weeks of therapy, and 3 months after treatment cessation. Patients were classified as responders (n ​= ​11) if a reduction of ≥2 points in the Clinical Activity Score (CAS) was observed.

RESULTS

A significant decrease in exophthalmos, muscles' thickness and CAS value was demonstrated after MP treatment in responders group. Significantly higher concentrations were found in baseline IL-23 between the GD and GO groups compared to controls. No statistically significant differences in serum concentrations of IL-17 and IL-23 were observed during treatment with MP and 3 months after treatment cessation. A statistically significant reduction in TSHRab concentration was demonstrated 3 months after treatment cessation compared to baseline values in responders group.

CONCLUSIONS

Low baseline IL-17 concentration, in addition to high TSHRab titre, serves as marker of disease activity. Although, we expect that low IL-23 concentration, in addition to high TSHRab titre, could be used as predictors of disease activity and a prognostic factor of response to immunosuppressive therapy in GO.

Current status and relevance of single nucleotide polymorphisms in IL-6-/IL-12-type cytokine receptors

Cytokines control immune related events and are critically involved in a plethora of patho-physiological processes including autoimmunity and cancer development. In rare cases, single nucleotide polymorphisms (SNPs) or single nucleotide variations (SNVs) in cytokine receptors eventually cause detrimental ligand-independent, constitutive activation of signal transduction. Most SNPs have, however, no or only marginal influences on gene expression, protein stability, localization and function and thereby only slightly affecting pathogenesis probability. The SNP database (dbSNP) is an archive for a broad collection of polymorphisms in which SNPs are categorized and marked with a locus accession number "reference SNP" (rs). Here, we engineered an algorithm to directly align dbSNP information to DNA and protein sequence information to clearly illustrate a genetic SNP landscape exemplified for all tall cytokine receptors of the IL-6/IL-12 family, including IL-23R, IL-12Rβ1, IL-12Rβ2, gp130, LIFR, OSMR and WSX-1. This information was complemented by a comprehensive literature summary and structural insights of relevant disease-causing SNPs in cytokine/cytokine receptor interfaces. In summary, we present a general strategy with potential to apply to other cytokine receptor networks.

Association of Other Autoimmune Diseases With Thyroid Eye Disease

BACKGROUND

Thyroid eye disease (TED) is a potentially disfiguring and sight-threatening autoimmune (AI) orbitopathy, affecting up to 400,000 people in the UK. There are no accurate early predictors of TED severity. Although polyautoimmunity has been shown to affect AI disease severity, its influence on TED severity has never been investigated. The prevalence of polyautoimmunity among TED patients is also unclear, with discordant results reported in the literature. This study evaluates the prevalence of non-thyroid/"other" AI (OAI) conditions in an ethnically diverse TED cohort and assesses how polyautoimmunity affects TED severity and activity.

METHODS

A retrospective study of patients presenting to multidisciplinary TED clinics across three North-West London hospitals between 2011 and 2019. Data collected included: 1) demographics; 2) OAI conditions and management; 3) endocrine management of thyroid dysfunction; 4) details of TED and clinical activity score at presentation.

RESULTS

Two hundred and sixty-seven patients with a median age of 46 (35-54) years were included, 79.4% were female and 55% were Black, Asian and minority ethnic (BAME). Thirty-seven patients (13.9%) had OAI conditions, with rheumatoid arthritis (3.7%), vitiligo (3.0%) and psoriasis (3.0%) among the most prevalent. Of patients with OAI conditions, 43.2% (16/37) required immunosuppression prior to TED onset. Non-immunosuppressed patients with OAI conditions had a significantly higher clinical activity score at presentation than TED-only and previously immunosuppressed patients (p=0.02). No significant differences were observed in thyroid receptor antibody titers between these groups.

CONCLUSIONS

This study finds a 13.9% prevalence of OAI conditions among TED patients. Patients with OAI conditions overall have a tendency for more severe and significantly more clinically active TED than those without OAI conditions. Larger, prospective studies are warranted to further evaluate polyautoimmunity as an early predictor of TED severity.

Mechanisms That Underly T Cell Immunity in Graves' Orbitopathy

Graves' orbitopathy (GO), also known as thyroid-associated ophthalmopathy, is the most common ocular abnormality of Graves' disease. It is a disfiguring, invalidating, and potentially blinding orbital disease mediated by an interlocking and complicated immune network. Self-reactive T cells directly against thyroid-stimulating hormone receptor-bearing orbital fibroblasts contribute to autoimmune inflammation and tissue remodeling in GO orbital connective tissues. To date, T helper (Th) 1 (cytotoxic leaning) and Th2 (antibody leaning) cell subsets and an emerging role of Th17 (fibrotic leaning) cells have been implicated in GO pathogenesis. The potential feedback loops between orbital native residential CD34^- fibroblasts, CD34⁺ infiltrating fibrocytes, and effector T cells may affect the T cell subset bias and the skewed pattern of cytokine production in the orbit, thereby determining the outcomes of GO autoimmune reactions. Characterization of the T cell subsets that drive GO and the cytokines they express may significantly advance our understanding of orbital autoimmunity and the development of promising therapeutic strategies against pathological T cells.

Elevated IL-38 inhibits IL-23R expression and IL-17A production in thyroid-associated ophthalmopathy

IL-23/IL-23R and PGE₂/EP2+EP4 have been recognized as crucial signals that promote Th17 differentiation in many autoimmune diseases, including thyroid-associated ophthalmopathy (TAO). However, the interactive role of IL-23R in IL-23/Th17 signaling and PGE₂/Th17 signaling has not been clarified in TAO. Furthermore, the role of IL-38, a novel anti-inflammatory cytokine, has not been explored in TAO. Thus, we aimed to investigate the roles of IL-23R and IL-38 in the pathogenesis of TAO. Activated peripheral blood mononuclear cells (PBMCs) were cultured with or without IL-23 and PGE₂. The results showed that IL-23R and IL-17A were upregulated to different degrees and reached the highest levels with both stimuli, indicating that IL-23 induced PBMCs to secrete PGE₂, which further boosted the proportion of IL-23R+CD4+T cells to promote IL-17A secretion. Pretreatment with antagonists aimed at EP2/EP4 receptors diminished PGE₂-induced upregulation of IL-23R and IL-17A. IL-38 in TAO patients was increased. Activated orbital fibroblasts (OFs) and PBMCs were pretreated with different concentrations of IL-38. IL-23R and IL-17A expression in circulating PBMCs and IL-6 and IL-8 in resident OFs were suppressed by IL-38 at relatively low concentrations. Our findings suggest that the feedback loop of IL-23/IL-23R/PGE₂/EP2+EP4/IL-23R/IL-17A plays a significant role in the pathogenesis of TAO and that IL-23R is one of the key targets. Increased IL-38 in TAO could not only inhibit the expression of IL-23R and IL-17A in PBMCs but also suppress inflammation in OFs. Therapies targeting IL-23R may be effective, and IL-38 could be a potential therapeutic approach for TAO.

The Association Study of IL-23R Polymorphisms With Cerebral Palsy in Chinese Population

Background: Cerebral palsy (CP) is a syndrome of non-progressive motor dysfunction caused by early brain development injury. Recent evidence has shown that immunological abnormalities are associated with an increased risk of CP.

Methods: We recruited 782 children with CP as the case group and 770 healthy children as the control group. The association between IL-23R single nucleotide polymorphisms (SNPs; namely, rs10889657, rs6682925, rs1884444, rs17375018, rs1004819, rs11805303, and rs10889677) and CP was studied by using a case–control method and SHEsis online software. Subgroup analysis based on complications and clinical subtypes was also carried out.

Results: There were differences in the allele and genotype frequencies between CP cases and controls at the rs11805303 and rs10889677 SNPs (Pallele = 0.014 and 0.048, respectively; Pgenotype = 0.023 and 0.008, respectively), and the difference in genotype frequency of rs10889677 remained significant after Bonferroni correction (Pgenotype = 0.048). Subgroup analysis revealed a more significant association of rs10889677 with CP accompanied by global developmental delay (Pgenotype = 0.024 after correction) and neonatal encephalopathy (Pgenotype = 0.024 after correction).

Conclusion: The present results showed a significant association between IL-23R and CP, suggesting that IL-23R may play a potential role in CP pathogenesis.

IL-12 and IL-23-Close Relatives with Structural Homologies but Distinct Immunological Functions

Cytokines of the IL-12 family show structural similarities but have distinct functions in the immune system. Prominent members of this cytokine family are the pro-inflammatory cytokines IL-12 and IL-23. These two cytokines share cytokine subunits and receptor chains but have different functions in autoimmune diseases, cancer and infections. Accordingly, structural knowledge about receptor complex formation is essential for the development of new therapeutic strategies preventing and/or inhibiting cytokine:receptor interaction. In addition, intracellular signaling cascades can be targeted to inhibit cytokine-mediated effects. Single nucleotide polymorphisms can lead to alteration in the amino acid sequence and thereby influencing protein functions or protein–protein interactions. To understand the biology of IL-12 and IL-23 and to establish efficient targeting strategies structural knowledge about cytokines and respective receptors is crucial. A highly efficient therapy might be a combination of different drugs targeting extracellular cytokine:receptor assembly and intracellular signaling pathways.

From genes polymorphisms to mucosal expression of cytokines: evaluating IL-23/IL-17 axis in adult patients with gastritis

Background and Objective

Chronic inflammation is the typical sign of gastritis that may shift into gastric cancer. IL-17A and IL-17F as a novel inflammatory cytokines subset of CD4+Th play the main role in inflammation. A key cytokine receptor in the inflammatory IL-17/IL-23 axis, the interleukin 23 receptor (IL23R), may be related to gastritis. We evaluated the correspondence between IL-17A G197A, IL-17F A7488G and IL23R+2199 A/C polymorphisms with TGF-β1, IL-6, IL-17, IL-21 and IL-23 mucosal mRNAs expression in uninfected H. Pylori (HP) chronic gastritis patients.

Materials and Methods

Total RNA and genomic DNA were separated from gastric biopsies of 44 patients with gastritis. Subsequently, mucosal mRNAs expression of TGF-β1, IL-6, IL-17, IL-21 and IL-23 were assessed by real-time PCR. To polymorphisms determination of IL-17A G197A, IL-17F A7488G and IL-23R +2199A/C the PCR-RFLP was used in gastric biopsies.

Results

Results point that IL-17A G197A, IL-17F A7488G and IL23R +2199A/C polymorphisms did not influence the mucosal expression of TGF-β1, IL-6, IL-17 and IL-21 (p> 0.05). In an opposite result, we don't find a correspondence between IL-17A G197A, IL-17F A7488G polymorphisms and mucosal expression of IL-23 (p> 0.05). In a contrary, we found a correlation between IL23R +2199A/C polymorphism and mucosal expression of IL-23 in patients with chronic gastritis (p< 0.05).

Conclusion

These findings propose that IL23R +2199A/C polymorphism may change the mucosal expression of IL-23 pattern in patients with gastritis disease in the absence of HP, but to support the conclusion, more research may be required.

Progress in the pathogenesis of thyroid-associated ophthalmopathy and new drug development

Thyroid-associated ophthalmopathy (TAO) is the most common extrathyroidal manifestation of toxic diffuse goiter (Graves' disease), also known as Graves' ophthalmopathy/orbitopathy. As an organ-specific autoimmune disease, the pathogenesis of TAO is still unclear. In recent years, great progress has been made in revealing the mechanism of TAO. Various biological and immunosuppressive agents have emerged in an endless stream, showing encouraging results. Strengthening the basic research, establishing ideal animal models, deeply understanding the pathogenesis, and developing novel targeted drugs are of great significance to guide the clinical diagnosis and management of TAO and improve the prognosis of patients.

Slit2 May Underlie Divergent Induction by Thyrotropin of IL-23 and IL-12 in Human Fibrocytes

IL-23 and IL-12, two structurally related heterodimeric cytokines sharing a common subunit, divergently promote Th cell development and expansion. Both cytokines have been implicated in the pathogenesis of thyroid-associated ophthalmopathy (TAO), an autoimmune component of Graves disease. In TAO, CD34+ fibrocytes, putatively derived from bone marrow, can be identified in the orbit. There they masquerade as CD34+ orbital fibroblasts (OF) (CD34+ OF) and cohabitate with CD34- OF in a mixed fibroblast population (GD-OF). Slit2, a neural axon repellent, is expressed and released by CD34- OF and dampens the inflammatory phenotype of fibrocytes and CD34+ OF. In this study we report that thyrotropin (TSH) and the pathogenic, GD-specific monoclonal autoantibody, M22, robustly induce IL-23 in human fibrocytes; however, IL-12 expression is essentially undetectable in these cells under basal conditions or following TSH-stimulation. In contrast, IL-12 is considerably more inducible in GD-OF, cells failing to express IL-23. This divergent expression and induction of cytokines appears to result from cell type-specific regulation of both gene transcription and mRNA stabilities. It appears that the JNK pathway activity divergently attenuates IL-23p19 expression while enhancing that of IL-12p35. The shift from IL-23p19 expression in fibrocytes to that of IL-12p35 in their derivative CD34+ OF results from the actions of Slit2. Thus, Slit2 might represent a molecular determinant of balance between IL-23 and IL-12 expression, potentially governing immune responses in TAO.

Efficacy and safety of tripterygium glycosides for Graves ophthalmopathy: A systematic review and meta-analysis

BACKGROUND

Graves ophthalmopathy (GO) is one of the remaining enigmas in thyroidology. Glucocorticoids (GCs) are strongly recommended but their effects are not completely satisfactory and adverse reactions can occur. Tripterygium glycosides (TG) is a promising component extracted from Tripterygium wilfordii Hook F (TwHF), and numerous patients with GO have benefited from it. However, its practical application value is still unclear. The aim of this systematic review and meta-analysis was to investigate the efficacy and safety of TG for patients with GO.

METHODS

By retrieving the PubMed, Embase, the Cochrane Library, CNKI, VIP, CBM, and WanFang Databases, the open published randomized controlled trials (RCTs) related to TG in the treatment of GO were collected. And inclusion and exclusion criteria were established. The Cochrane bias risk assessment tool conducts the evaluation of included studies, and meta-analysis was performed using Revman 5.3 software.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42019131915.

RESULTS

A total of 19 trials (involving 1517 GO patients) were included in this review with generally acceptable validity of included RCTs. TG therapy brought about a significantly higher efficacy rate compared with non-TG treatments (RR: 1.40; 95% CI: 1.31-1.49). Subgroup meta-analysis showed that TG with or without immunosuppressive therapies were all better than controls: with GC (RR: 1.36; 95% CI: 1.27-1.46), with multiple intensification of immunosuppressive therapies (RR: 1.91; 95% CI: 1.37-2.67), with no immunosuppressive therapies (RR: 1.39; 95% CI:1.21-1.59); the dosage of TG for 15-60 mg/d (RR: 1.41; 95% CI: 1.30-1.53) were better compared with for ≥90 mg/d (RR: 1.47; 95% CI: 1.29-1.68); the course of treatment for ≤3 months (RR: 1.43; 95% CI: 1.33-1.52) was better than controls, but when >3 months (RR: 1.15; 95% CI: 0.94-1.41) there was no significant differences. After treatment, the degree of exophthalmus (SMD: -2.55; 95% CI: -2.93 to 2.17), the recurrence rate of 1 year (RR: 0.45; 95% CI: 0.27-0.74), and adverse reactions rate (RR: 0.32; 95% CI: 0.20-0.53) were all lower, while the CAS was no obvious gap in 2 groups (SMD: 0.08; 95% CI: -0.60 to 0.75).

CONCLUSIONS

This review found that TG has some advantages in treating GO, especially in improving clinical efficacy and reducing adverse reactions. Nevertheless, large sample, multi-center, reasonable design, and high quality clinical studies are still needed for further verification.

Hidradenitis Suppurativa and Thyroid Disease: Systematic Review and Meta-Analysis

Background:

Hidradenitis suppurativa (HS) is a chronic inflammatory disease characterized by painful nodules, sinus tracts, and significant scarring. Although the pathogenesis of this disease is not well established, there is increasing evidence to suggest that it is an immune-mediated disorder. Previous studies have suggested a relationship between HS and thyroid disease, which is also driven by an autoimmune process. We sought to assess whether an association exists between HS and thyroid disease.

Objectives:

To determine whether HS is associated with thyroid disease via meta-analysis of case-control studies.

Methods:

A systematic review and meta-analysis was performed according to recommended PRISMA guidelines. Electronic searches were performed using 6 electronic databases from their inception until August 2018. Data were extracted and analyzed according to predefined clinical endpoints. Odds ratio (OR) was used as the summary effect size.

Results:

We identified 5 case-controls studies included for meta-analysis. There were a total of 36 103 HS cases compared with 170 517 control cases. We found a significant association between HS and thyroid disease (OR 1.36, 95% CI 1.13-1.64, I 2 = 78%, P = .001).

Conclusions:

This pooled analysis of existing case-control studies to date supports an association between HS and any thyroid disease. Clinicians treating patients with HS should be aware of this potential association with thyroid disease.

Interleukin-23 receptor (IL-23R) gene polymorphisms and haplotypes associated with the risk of preeclampsia: evidence from cross-sectional and in silico studies

PURPOSE

Pre-eclampsia is a relatively common pregnancy disorder. Serum concentrations of certain pro-inflammatory molecules and cytokines like interleukin-23 may affect the pathogenesis of pre-eclampsia. The interleukin-23 receptor (IL-23R) gene plays an important role in the progression of inflammatory and autoimmune diseases and IL-23 polymorphisms might influence the susceptibility of pre-eclampsia. The aim of the recent study was to establish the association between IL-23R gene polymorphisms and the susceptibility for developing of pre-eclampsia.

METHODS

One hundred and fifty-eight pregnant patients with pre-eclampsia and 153 controls were genotyped using RFLP-PCR and AS-PCR. Also, an in silico analysis was performed to predict possible effects of these variations on IL-23R mRNA and protein structures.

RESULTS

The frequency of the AG genotype of rs11209026 is related to a higher risk of pre-eclampsia. The mutant C and A allele in rs10889677 and rs11209026 SNPs, respectively, are correlated with the risk of pre-eclampsia and they are more frequent in severe late onset PE. We found higher frequency of the haplotype CG in patients with pre-eclampsia in comparison to healthy controls, as well as, the CG haplotype frequency significantly increased the risk of PE in severe, early onset, and late onset sub-groups. The results of computational analysis predicted rs11209026 and rs10889677 SNPs as functional variations, which can influence IL-23R mRNA and protein.

CONCLUSIONS

The results of present study show positive association between polymorphisms in the IL-23R gene and pre-eclampsia. Therefore, the presence of IL-23R rs11209026, rs10889677 polymorphism might be markers for the genetic susceptibility to pre-eclampsia.

Upregulated tissue expression of T helper (Th) 17 pathogenic interleukin (IL)-23 and IL-1β in Hashimoto's thyroiditis but not in Graves' disease

T helper (Th) 17 cells and interleukin (IL)-17 play a significant role in the pathogenesis of autoimmune thyroid disease (AITD). However, it has recently become clear that Th17 cells are more heterogeneous and exhibit two different phenotypes, whereas IL-23 and IL-1β are crucial for the generation of pathogenic Th17 lymphocytes. We aimed to investigate the association between IL-17 and Th17-promoting cytokines in AITD by studying the immunoexpression patterns of IL-17, IL-23, and IL-1β in thyroid tissue. Following thyroidectomy, 29 patients with AITD (21 cases of Hashimoto's thyroiditis (HT) and 8 cases of Graves' disease (GD)) and 18 patients with colloid goiter, as controls, were enrolled in this study, and immunohistochemistry was performed. The expression level of IL-17 in thyrocytes was significantly higher in HT and GD patients than in colloid goiter patients. Immunopositivity for both IL-23 and IL-1β was significantly increased in HT patients compared to GD and colloid goiter patients. However, no difference was found between IL-23 or IL-1β expression in patients with GD and colloid goiter. A positive correlation between IL-17 and IL-23 as well as IL-17 and IL-1β expression was observed in HT patients (r = 0.574, p = 0.007 and r = 0.461, p = 0.036, respectively). In the GD group, IL-17 was positively correlated with IL-1β (r = 0.817, p = 0.013) but not with IL-23 expression. We found increased IL-23 and IL-1β expression in the HT group but not in the GD group. Furthermore, both interleukins were correlated with IL-17 immunopositivity in thyroid tissue, suggesting that pathogenic Th17-promoting cytokines may play a role in HT pathogenesis.

Interaction Between CCR6+ Th17 Cells and CD34+ Fibrocytes Promotes Inflammation: Implications in Graves' Orbitopathy in Chinese Population

Purpose

Recent reports suggest that Th17 immunity and bone marrow-derived CD34+ fibrocytes contribute to the pathogenesis of Graves' orbitopathy (GO). This study investigated interactions between Th17 cells and fibrocytes in GO inflammation in Chinese subjects.

Methods

Th17 cells and fibrocytes were derived from blood samples from Chinese GO patients and healthy controls. Proportions and phenotypes of Th17 cells, regulatory T cells (Tregs), and fibrocytes were examined by flow cytometry. Exogenous IL-17A was used to study inflammatory activity of fibrocytes from GO patients and control subjects. Coculture, quantitative RT-PCR, Luminex, and transwell assays were performed to investigate the relationship between Th17 cells and fibrocytes.

Results

CC-chemokine receptor 6 (CCR6+) Th17 cells were increased in both active (P < 0.001) and inactive (P < 0.05) GO patients, compared with healthy controls. There was a positive correlation between number of CCR6+ Th17 cells and GO clinical activity score (P < 0.0001, r = 0.8176). Further, CD34+ fibrocytes were increased in GO patients, with increased expression of IL-17RA (P < 0.05), CD80 (P < 0.05), and CD86 (P < 0.05). A decreased population of effector Treg cells (P < 0.01) and increased CTLA-4 expression on naïve Treg cells (P < 0.05) were observed in GO patients. IL-17A stimulated cytokine production in fibrocytes; GO fibrocytes exhibited more robust production than normal fibrocytes. Autologous Th17 cells promoted inflammatory and antigen-presenting functions of GO fibrocytes; conversely, fibrocytes enhanced Th17 cell-function and recruited Th17 cells in a macrophage inflammatory protein 3 (MIP-3)/CCR6-dependent manner.

Conclusions

The crosstalk between CCR6+ Th17 cells and fibrocytes plays a role in the pathogenesis of GO. Suppressing these interactions may be a candidate molecular target for therapeutic approaches of GO.

RNA-Sequencing Gene Expression Profiling of Orbital Adipose-Derived Stem Cell Population Implicate HOX Genes and WNT Signaling Dysregulation in the Pathogenesis of Thyroid-Associated Orbitopathy

Purpose

The purpose of this study was to characterize the intrinsic cellular properties of orbital adipose-derived stem cells (OASC) from patients with thyroid-associated orbitopathy (TAO) and healthy controls.

Methods

Orbital adipose tissue was collected from a total of nine patients: four controls and five patients with TAO. Isolated OASC were characterized with mesenchymal stem cell-specific markers. Orbital adipose-derived stem cells were differentiated into three lineages: chondrocytes, osteocytes, and adipocytes. Reverse transcription PCR of genes involved in the adipogenesis, chondrogenesis, and osteogenesis pathways were selected to assay the differentiation capacities. RNA sequencing analysis (RNA-seq) was performed and results were compared to assess for differences in gene expression between TAO and controls. Selected top-ranked results were confirmed by RT-PCR.

Results

Orbital adipose-derived stem cells isolated from orbital fat expressed high levels of mesenchymal stem cell markers, but low levels of the pluripotent stem cell markers. Orbital adipose-derived stem cells isolated from TAO patients exhibited an increase in adipogenesis, and a decrease in chondrogenesis and osteogenesis. RNA-seq disclosed 54 differentially expressed genes. In TAO OASC, expression of early neural crest progenitor marker (WNT signaling, ZIC genes and MSX2) was lost. Meanwhile, ectopic expression of HOXB2 and HOXB3 was found in the OASC from TAO.

Conclusion

Our results suggest that there are intrinsic genetic and cellular differences in the OASC populations derived from TAO patients. The upregulation in adipogenesis in OASC of TAO may be is consistent with the clinical phenotype. Downregulation of early neural crest markers and ectopic expression of HOXB2 and HOXB3 in TAO OASC demonstrate dysregulation of developmental and tissue patterning pathways.

Autoimmune thyroid diseases and Th17/Treg lymphocytes

Years of researches have demonstrated that the imbalance of Th17 and Tregs contribute to the thyroid autoimmunity and the severity of autoimmune thyroid disease (AITD). The underlying mechanism comprises inherent genetic predisposition, abnormality of Th17 and Treg related biological molecules, and gut microbiota disorder. New therapeutic strategies have been developed to improve the Th17/Treg equilibrium, including regulation of intracellular signaling pathways, neutralization of Th17-related cytokines, as well as manipulation of Th17 and Treg specific transcription factors. Although a few of these agents are applied into AITD, the clinic prospect is promising.

Characterization of variations in IL23A and IL23R genes: possible roles in multiple sclerosis and other neuroinflammatory demyelinating diseases

Multiple sclerosis is among the most serious inflammatory demyelinating diseases (IDD). Interleukin-23A (IL23A) regulates and coordinates the activities of immune cells by interacting with its receptor IL23R and plays key roles in the pathogenesis of immune inflammatory diseases. IDD, deemed to be a kind of autoimmune diseases, may involve IL23A in the pathogenesis. The aim of this work was to validate the hypothesized involvement of IL-23A and its receptor in IDD. We sequenced the IL-23A and IL-23R genes for 206 Chinese Han IDD patients and evaluated SNPs within or near those genes. The serum levels of IL23A in IDD participants were analyzed using ELISA. The statistical analyses were conducted using Chi-Square Tests as implemented in SPSS (version 19.0). The Hardy-Weinberg equilibrium test of the population was carried out using online software OEGE. Three variants rs2066808, rs2371494, rs11575248 in IL-23A gene and one variant rs1884444 in IL-23R gene were demonstrated to be associated with the risk of MS or other IDD diseases, and the expression level of serum IL-23A in the MS patients was also altered. We conclude that variants in IL-23A and IL-23R genes were associated with the risk of MS or other IDD diseases.

The thyroid, the eyes and the gut: a possible connection

INTRODUCTION

Graves' disease (GD) is an autoimmune disorder responsible for 60-90% of thyrotoxicosis, with an incidence of 1 to 2 cases per 1000 population per year in England. Graves' orbitopathy (GO) is the most frequent extrathyroidal manifestation, not provoked directly by abnormal thyroid hormone levels, but by the consequence of the underlying autoimmune process. The aetiology of autoimmune disorders is due to an interplay between susceptibility genes and environmental factors, such as infections and stress. What triggers the autoimmune reaction to a specific site of the body is not yet clearly understood. The lack of knowledge in GD and GO pathogenesis implicates therapies that only limit damage but do not prevent disease onset.

MATERIAL AND METHODS

We performed on PubMed and the Cochrane Library a literature search for the articles published until July 2016 by using the search terms 'graves disease' and 'microbiome', 'orbitopathy' and 'autoimmune pathogenesis'. Reference lists of relevant studies were hand-searched for additional studies.

CONCLUSION

In this scenario, a Marie Sklodowska-Curie funded project INDIGO ( http://www.indigo-iapp.eu/ ) is investigating the role of the gut bacteria in GD and GO pathogenesis. The gut is the first and the widest area of bacteria access, with the highest concentration of T cells in the human body and trained to react to microorganisms. Interestingly, all the environmental factors involved in GD and GO pathogenesis can alter the balance within the microorganisms located in the gut, and influence the immune system, in particular the proportions of regulatory Treg and inflammatory TH17 cells. It is hoped that investigating GD and GO pathogenesis from this novel aspect will identify new targets for prevention and treatment.

Haplotype of non-synonymous mutations within IL-23R is associated with susceptibility to severe malaria anemia in a P. falciparum holoendemic transmission area of Kenya

Background

Improved understanding of the molecular mechanisms involved in pediatric severe malarial anemia (SMA) pathogenesis is a crucial step in the design of novel therapeutics. Identification of host genetic susceptibility factors in immune regulatory genes offers an important tool for deciphering malaria pathogenesis. The IL-23/IL-17 immune pathway is important for both immunity and erythropoiesis via its effects through IL-23 receptors (IL-23R). However, the impact of IL-23R variants on SMA has not been fully elucidated.

Methods

Since variation within the coding region of IL-23R may influence the pathogenesis of SMA, the association between IL-23R rs1884444 (G/T), rs7530511 (C/T), and SMA (Hb < 6.0 g/dL) was examined in children (n = 369, aged 6–36 months) with P. falciparum malaria in a holoendemic P. falciparum transmission area.

Results

Logistic regression analysis, controlling for confounding factor of anemia, revealed that individual genotypes of IL-23R rs1884444 (G/T) [GT; OR = 1.34, 95% CI = 0.78–2.31, P = 0.304 and TT; OR = 2.02, 95% CI = 0.53–7.74, P = 0.286] and IL-23R rs7530511 (C/T) [CT; OR = 2.6, 95% CI = 0.59–11.86, P = 0.202 and TT; OR = 1.66, 95% CI = 0.84–3.27, P = 0.142] were not associated with susceptibility to SMA. However, carriage of IL-23R rs1884444T/rs7530511T (TT) haplotype, consisting of both mutant alleles, was associated with increased susceptibility to SMA (OR = 1.12, 95% CI = 1.07–4.19, P = 0.030).

Conclusion

Results presented here demonstrate that a haplotype of non-synonymous IL-23R variants increase susceptibility to SMA in children of a holoendemic P. falciparum transmission area.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2404-y) contains supplementary material, which is available to authorized users.

Thyroid-associated Ophthalmopathy

Thyroid-associated ophthalmopathy is the most frequent extrathyroidal involvement of Graves’ disease but it sometimes occurs in euthyroid or hypothyroid patients. Thyroid-associated ophthalmopathy is an autoimmune disorder, but its pathogenesis is not completely understood. Autoimmunity against putative antigens shared by the thyroid and the orbit plays a role in the pathogenesis of disease. There is an increased volume of extraocular muscles, orbital connective and adipose tissues. Clinical findings of thyroid-associated ophthalmopathy are soft tissue involvement, eyelid retraction, proptosis, compressive optic neuropathy, and restrictive myopathy. To assess the activity of the ophthalmopathy and response to treatment, clinical activity score, which includes manifestations reflecting inflammatory changes, can be used. Supportive approaches can control symptoms and signs in mild cases. In severe active disease, systemic steroid and/or orbital radiotherapy are the main treatments. In inactive disease with proptosis, orbital decompression can be preferred. Miscellaneous treatments such as immunosuppressive drugs, somatostatin analogs, plasmapheresis, intravenous immunoglobulins and anticytokine therapies have been used in patients who are resistant to conventional treatments. Rehabilitative surgeries are often needed after treatment.

The obesity-related pathology and Th17 cells

Chronic inflammation associated with obesity plays a major role in the development of metabolic diseases, cancer, and autoimmune diseases. Among Th subsets, Th17 cells are involved in the pathogenesis of autoimmune disorders such as psoriasis, rheumatoid arthritis, inflammatory bowel disease, steroid-resistant asthma, and multiple sclerosis. Accumulating data suggest that reciprocal interactions between the metabolic systems and immune system play pivotal roles in the pathogenesis of obesity-associated diseases. We herein outline the developing principles in the control of T cell differentiation and function via their cellular metabolism. Also discussed are recent findings that changes in the intracellular metabolism, including fatty acid metabolism, affect the Th17 cell function in obese individuals. Finally, we will also highlight the unique molecular mechanism involved in the activation of retinoid-related orphan receptor-gamma-t (RORγt) by intracellular metabolism and discuss a new therapeutic approach for treating autoimmune disorders through the inhibition of RORγt.

IL23R single nucleotide polymorphisms could be either beneficial or harmful in ulcerative colitis

AIM

To investigate the association of seven single nucleotide polymorphisms (SNPs) of the IL23R gene with the clinical picture of ulcerative colitis (UC).

METHODS

Genomic DNA samples of 131 patients (66 males, 65 females, mean age 55.4 ± 15.8 years) with Caucasian origin, diagnosed with UC were investigated. The diagnosis of UC was based on the established clinical, endoscopic, radiological, and histopathological guidelines. DNA was extracted from peripheral blood leukocytes by routine salting out method. Polymerase chain reaction and restriction fragment length polymorphism were used to identify the alleles of seven SNPs of IL23R gene (rs11209026, rs10889677, rs1004819, rs2201841, rs7517847, rs10489629, rs7530511).

RESULTS

Four out of seven analyzed SNPs had statistically significant influence on the clinical picture of UC. Two SNPs were associated with greater colonic extension (rs2201841 P = 0.0084; rs10489629 P = 0.0405). For two of the SNPs, there was more frequently need for operations (rs2201841 P = 0.0348, OR = 8.0; rs10889677 P = 0.0347, OR = 8.0). The rs2201841 showed to be a risk factor for the development of iron deficiency (P = 0.0388, OR = 6.1837). For patients with the rs10889677, a therapy with azathioprine was more frequently necessary (P = 0.0116, OR = 6.1707). Patients with rs10489629 SNP had a lower risk for weight loss (P = 0.0169, OR = 0.3394). Carriers of the heterozygous variant had a higher risk for an extended disease (P = 0.0284). The rs7517847 showed a protective character leading to mild bowel movements. Three SNPs demonstrated no statistically significant influence on any examined clinical features of UC.

CONCLUSION

We demonstrated susceptible or protective character of the investigated IL23R SNPs on the phenotype of UC, confirming the genetic association.

IL-17A Exacerbates Fibrosis by Promoting the Proinflammatory and Profibrotic Function of Orbital Fibroblasts in TAO

CONTEXT

The development of thyroid-associated ophthalmopathy (TAO) is associated with self-immune dysfunction. Recent findings in TAO and Graves' disease indicate that IL-17A may also be involved in the autoimmunity of TAO.

OBJECTIVE

We sought to investigate the pathogenic function of IL-17A-producing T cells in TAO.

DESIGN/SETTING/PARTICIPANTS

Blood samples and orbital fibroblasts (OFs) were collected from TAO patients and healthy subjects.

MAIN OUTCOME MEASURES

Flow cytometry, real-time PCR, cytokine-specific ELISA, and Western blotting were performed.

RESULTS

Here, we showed a significantly higher proportion of IL-17A-producing T cells in TAO patients and the recruitment of both CD4(+) and CD8(+) T cells in TAO orbits. TAO orbital tissues expressed more IL-17A receptor, IL-17A, and its related cytokines, with severe fibrotic change compared with normal controls. Furthermore, we validated that IL-17A could enhance the proinflammatory function of OFs and stimulate the production of extracellular matrix proteins in OFs but not eyelid fibroblasts. The mechanisms involved in this enhancement mainly relied on MAPK activation. Finally, we observed that the deubiquitinase inhibitor vialinin A could down-regulate retinoic acid receptor-related orphan receptor-γt expression and decrease IL-17A level in TAO patients.

CONCLUSION

Our observations illustrate the potential pathogenic role of IL-17A-producing T cells in the inflammatory response and fibrosis of TAO. The effect of vialinin A on the reduction of retinoic acid receptor-related orphan receptor-γt level implicates its potential role as a novel therapeutic agent for TAO and other autoimmune disorders in the future.

T regulatory (Treg) and T helper 17 (Th17) lymphocytes in thyroid autoimmunity

Different immune cell subsets have a relevant role in the pathogenesis of and tissue damage seen in autoimmune thyroid diseases (AITD), including T regulatory (Treg) lymphocytes and T helper (Th) 17 cells. There are several types of CD4+ Treg cells (Foxp3+, CD69+, Tr1), which are able to prevent the appearance of autoimmune diseases, down regulating the immune response and the inflammatory phenomenon. However, despite their presence in peripheral blood and thyroid tissue from patients with AITD, these cells are apparently unable to put down the autoimmune process. Moreover, many reports indicate the involvement of Th17 cells in chronic inflammatory diseases, including AITD. Nevertheless, it is now evident that these lymphocytes show a remarkable plasticity, giving rise to anti-inflammatory (including Treg lymphocytes) and pro-inflammatory cell subtypes. Nowadays, both Treg and Th17 cells must be considered as key elements in the pathogenesis of AITD as well as plausible potential targets for the next generation of therapeutic options of this condition.

Association between Polymorphism of Interleukin-23 Receptor and Hashimoto's Thyroiditis in Chinese Han Population of Shandong

Objective:

The interleukin-23 receptor (IL-23R) has been shown to be associated with autoimmune diseases in many different populations. This study aimed to investigate the association between IL-23R gene polymorphism and susceptibility to Hashimoto's thyroiditis (HT) in Chinese Han population of Shandong.

Methods:

A case–control cohort study was performed in 145 HT patients from First People's Hospital of Jining between February 2010 to October 2013 and 150 healthy controls. Two single nucleotide polymorphisms located in the promoter region of IL-23R gene (rs17375018 and rs7517847) were examined by polymerase chain reaction-restriction fragment length polymorphism analysis. Hardy-Weinberg equilibrium was performed using the Chi-square test. Genotype frequencies were estimated by direct counting, and allele and genotype frequencies between patients and controls were analyzed by the Chi-square test.

Results:

The rs17375018 GG genotype and the G allele were significantly increased in HT patients compared with healthy controls (P = 0.034 and P = 0.013, respectively). No association was identified between HT patients and healthy controls in rs7517847.

Conclusion:

The study demonstrated that polymorphism of IL-23R gene rs17375018 is highly associated with HT in Chinese Han population of Shandong, suggesting that IL-23R gene polymorphism (rs17375018 G) may play a critical role in susceptibility to HT.

Dissecting the Genetic Susceptibility to Graves' Disease in a Cohort of Patients of Italian Origin

Graves' disease (GD) is an autoimmune oligogenic disorder with a strong hereditary component. Several GD susceptibility genes have been identified and confirmed during the last two decades. However, there are very few studies that evaluated susceptibility genes for GD in specific geographic subsets. Previously, we mapped a new locus on chromosome 3q that was unique to GD families of Italian origin. In the present study, we used association analysis of single-nucleotide polymorphism (SNPs) at the 3q locus in a cohort of GD patients of Italian origin in order to prioritize the best candidates among the known genes in this locus to choose the one(s) best supported by the association. DNA samples were genotyped using the Illumina GoldenGate genotyping assay analyzing 690 SNP in the linked 3q locus covering all 124 linkage disequilibrium blocks in this locus. Candidate non-HLA (human-leukocyte-antigen) genes previously reported to be associated with GD and/or other autoimmune disorders were analyzed separately. Three SNPs in the 3q locus showed a nominal association (p < 0.05): rs13097181, rs763313, and rs6792646. Albeit these could not be further validated by multiple comparison correction, we were prioritizing candidate genes at a locus already known to harbor a GD-related gene, not hypothesis testing. Moreover, we found significant associations with the thyroid-stimulating hormone receptor (TSHR) gene, the cytotoxic T-lymphocyte antigen-4 (CTLA-4) gene, and the thyroglobulin (TG) gene. In conclusion, we identified three SNPs on chromosome 3q that may map a new GD susceptibility gene in this region which is unique to the Italian population. Furthermore, we confirmed that the TSHR, the CTLA-4, and the TG genes are associated with GD in Italians. Our findings highlight the influence of ethnicity and geographic variations on the genetic susceptibility to GD.

Genetic Associations of Interleukin-related Genes with Graves' Ophthalmopathy: a Systematic Review and Meta-analysis

Graves’ ophthalmopathy (GO) is the commonest extra-thyroidal manifestation of Graves’ disease (GD). Associations between interleukin-related (IL) gene polymorphisms and GO have been reported in different populations. We aim to confirm such associations by conducting a meta-analysis. Totally 382 publications were retrieved in MEDLINE and EMBASE up to 25/2/2015. After removing the duplicates and assessing the studies, we retrieved 16 studies that met the selection criteria for meta-analysis, involving 12 polymorphisms in 8 IL-related genes, and 1650 GO cases and 2909 GD controls. The summary odds ratio (OR) and 95% confidence intervals (CI) were estimated. We found one polymorphism in IL1A (rs1800587, c.-889C>T) showing a suggestive association with GO in the meta-analysis (allelic model [T vs. C]: OR = 1.62, 95% CI: 1.00–2.62, P = 0.050, I² = 53.7%; recessive model [TT vs. TC + CC]: OR = 2.39, 95% CI: 1.07–5.37, P = 0.039, I² = 23.6%; heterozygous model [TC vs. CC]: OR = 1.52, 95% CI: 1.04–2.22, P = 0.034, I² = 37.0%). No association with GO was detected for the other 7 genes (IL1B, IL1RA, IL4, IL6, IL12B, IL13 and IL23R). Our results thus indicate that IL1A is likely to be a genetic biomarker for GO. Further studies with larger sample sizes are warranted to confirm the associations of IL1A and other IL-related genes with GO.

The association of thyroid peroxidase antibody risk loci with susceptibility to and phenotype of Graves' disease

BACKGROUND

Despite great progress, the genetic basis of Graves' disease (GD) remains poorly understood. Recently, a population-based genomewide association study (GWAS) identified five novel loci (ATXN2/SH2B3, MAGI3, BACH2, TPO and KALRN) as significantly associated with the presence of thyroid peroxidase autoantibodies (TPOAbs), whereas several other loci showed suggestive association.

METHODS

In this study, we investigated 16 single nucleotide polymorphisms (SNPs) associated with TPOAbs for the association with susceptibility to and phenotype of GD in a cohort of 647 patients with GD and 769 controls from a Polish Caucasian population.

RESULTS

SNPs within/near HCP5 (rs3094228, P = 1·6 × 10(-12) , OR = 1·88), MAGI3 (rs1230666, P = 1·9 × 10(-5) , OR = 1·51) and ATXN2/SH2B3 (rs653178, P = 0·0015, OR = 1·28) loci were significantly associated with susceptibility to GD. Allele frequencies differed significantly in subgroups of patients with GD stratified by age of GD onset for HCP5 (P = 0·0014, OR = 1·50) and showed a suggestive difference for MAGI3 (P = 0·0035, OR = 1·50) SNPs. Although rs11675434 located near TPO showed no association with GD susceptibility, it was significantly associated with the presence of clinically evident Graves' ophthalmopathy (GO, P = 5·2 × 10(-5) , OR = 1·64), and this effect was independent from smoking status, age of GD onset and gender.

CONCLUSIONS

This is the first study showing an association of the ATXN2/SH2B3 locus with susceptibility to GD. Furthermore, we observed a novel significant association within the HLA region at a SNP located near HCP5 and confirmed the association of the MAGI3 locus with GD susceptibility. HCP5 and MAGI3 SNPs were further correlated with age of GD onset. Finally, we identified TPO as a new susceptibility locus for GO.

Associations between interleukin and interleukin receptor gene polymorphisms and risk of gout

Gout is a self-limiting, auto-inflammatory arthritis induced by the deposition of monosodium urate crystals in the synovial fluid and periarticular tissues. The aim of this study was to investigate the associations between genetic variants in the interleukin (IL) and interleukin receptor (ILR) genes IL-33, IL-1RL1, IL-23R, and signal transducer and activator of transcription 4 (STAT4) and susceptibility to gout in Chinese Han male individuals. The genetic distributions of rs3939286 in IL-33, rs13015714 in IL-1RL1, rs10889677 in IL-23R, and rs7574865 in STAT4 were detected in 1100 men with gout and 1227 ethnically matched controls, using Taqman allelic discrimination real-time polymerase chain reaction (PCR). Differences in these polymorphisms between the groups were investigated using χ(2) tests. The genotype-phenotype relationship among gout patients was tested by analysis of variance. There was a significant difference in genotypic frequencies of IL-23R rs10889677 between gout patients and controls (χ(2) = 81.386, P < 0.001). However, there were no significant differences in distributions of the other polymorphisms between the groups. Our results revealed that the rs10889677 variant in IL-23R may be involved in the development of gout in Chinese Han male individuals. However, further studies in other ethnic groups are needed to confirm these results.

Association of interleukin-23 receptor gene polymorphisms with risk of bladder cancer in Chinese

To assess whether polymorphisms of the interleukin-23 receptor (IL23R) gene are associated with bladder transitional cell carcinoma because chronic inflammation contributes to bladder cancer and the IL23R is known to be critically involved in the carcinogenesis of various malignant tumors. 226 patients with bladder cancer and 270 age-matched controls were involved in the study. Polymerase chain reaction-restriction fragment length polymorphism was used for genotyping. Genotype distribution and allelic frequencies between patients and controls were compared. In all three single nucleotide polymorphisms of IL23R studied, the distribution of genotype and allele frequencies of rs10889677 differed significantly between patients and controls. The frequency of allele C of rs10889677 was significantly increased in cases compared with controls (0.2898 vs. 0.1833, odds ratio 1.818, 95 % confidence interval 1.349-2.449). The result indicates that IL23R may play an important role in the susceptibility of bladder cancer in Chinese population.

Insights into IL-23 biology: From structure to function

Interleukin (IL-)23 is a central cytokine controlling TH17 development. Overshooting IL-23 signaling contribute to autoimmune diseases. Moreover, GWAS studies have identified several SNPs within the IL-23 receptor, which are associated with autoimmune diseases. IL-23 is a member of the IL-12-type cytokine family and consists of IL-23p19 and p40. Within the IL-12 family, IL-12 and IL-23 share the p40 cytokine subunit and the IL-12Rβ1 as one chain of the receptor complex. For signaling, IL-23 triggers heterodimerization of IL-12Rβ1 and the IL-23R. Subsequently, signal transduction pathways including JAK/STAT, MAPK and PI3K are activated. Most studies have investigated the biological relevance of IL-23 in the development of TH17 cells and autoimmunity, whereas less is known about the molecular context of IL-23 biology. Therefore, we focused on IL-23 receptor complex assembly, signal transduction and functional relevance of IL-23R SNPs in the context of IL-23-inhibitory principles.

Involvement of IL17A, IL17F and IL23R Polymorphisms in Colorectal Cancer Therapy

IL23/IL17 pathway plays an important role in the development of inflammatory bowel diseases (IBD). In general, the genes encoding the cytokines are genetically polymorphic and polymorphisms in genes IL23R and IL17 have been proved to be associated with its susceptibility to inflammatory diseases as well as cancer including colorectal cancer. Moreover, it has been shown that these interleukins are involved in anti-tumor or pro-tumor effects of various cancers. Previously, we showed that there is a significant association between IL17A, IL17F and IL23R polymorphisms as well as the occurrence of colorectal cancer and the clinical features of the disease. The purpose of the present work is to investigate an association between IL17A, IL17F and IL23R polymorphisms in 102 Tunisian patients with colorectal cancer treatment. The association was analyzed by statistical tools. We found that patients with mutated genotypes of IL17A G197A SNP could be a risk factor for the inefficiency of chemotherapy and radiotherapy. Unlike IL17F variant, patients with wild type genotypes require surgery and adjuvant chemotherapy. On the one hand, we found no evidence that supports a significant association between IL23R polymorphism and the combined genotypes of these three genes and the colorectal cancer treatment. On the other hand, we showed that there is an important interaction between IL17A/IL17F polymorphisms and the stage of the disease as well as its treatment. Finally, patients with IL17F wild type genotype highlighted that there is a valid longer OS without all treatments and with radiotherapy and a neoadjuvant chemotherapy. In contrast, we observed that there are no relationships between IL17A, IL23R and the survival of these patients neither with nor without the treatment. Our results suggest that polymorphisms in IL17A and IL17F genes may be a predictive source of colorectal cancer therapy type. Therefore, IL17F may serve as an independent prognostic factor for overall survival in patients with colorectal cancer.

Defining the functional states of Th17 cells

The molecular mechanisms governing T helper (Th) cell differentiation and function have revealed a complex network of transcriptional and protein regulators. Cytokines not only initiate the differentiation of CD4 Th cells into subsets but also influence the identity, plasticity and effector function of a T cell. Of the subsets, Th17 cells, named for producing interleukin 17 (IL-17) as their signature cytokine, secrete a cohort of other cytokines, including IL-22, IL-21, IL-10, IL-9, IFNγ, and GM-CSF.  In recent years, Th17 cells have emerged as key players in host defense against both extracellular pathogens and fungal infections, but they have also been implicated as one of the main drivers in the pathogenesis of autoimmunity, likely mediated in part by the cytokines that they produce. Advances in high throughput genomic sequencing have revealed unexpected heterogeneity in Th17 cells and, as a consequence, may have tremendous impact on our understanding of their functional diversity. The assortment in gene expression may also identify different functional states of Th17 cells. This review aims to understand the interplay between the cytokine regulators that drive Th17 cell differentiation and functional states in Th17 cells.

The human IL-23 receptor rs11209026 A allele promotes the expression of a soluble IL-23R-encoding mRNA species

The human IL23R gene single nucleotide polymorphism rs11209026 A allele confers protection against inflammatory diseases. However, although this difference has been associated with reductions in IL-23-induced IL-17A production and STAT3 phosphorylation, the molecular mechanism underlying these changes remains undefined. Th17 cell maturation depends on IL-23 signaling. Multiple splice forms of the human IL23R transcript exist, and one, Δ9, encodes a soluble form of the receptor. In this study, we asked whether this protective allele was associated with mRNA splicing. Using mini-gene constructs and competitive oligonucleotide binding, we showed that the A allele alters IL-23R α-chain mRNA splicing and favors exon 9 skipping by reducing the binding of the splicing enhancer SF2. This enhances expression of the Δ9 mRNA and consequently diminishes IL-23 signaling. Thus, the presence of the A allele increases expression of the soluble form of IL23R mRNA (which then functions as a decoy receptor) and lowers the ability to develop a Th17 phenotype upon IL-23 stimulation. We further showed that antisense oligonucleotides targeting the SF2 binding site could efficiently induce exon 9 skipping in the presence of the G allele, and thereby replicate the effect of the A allele. Antisense oligonucleotide treatment caused dose-responsive induction of the IL23RΔ9 mRNA and interfered with in vitro differentiation of human Th17 cells, reducing their expression of the signature Th17 cytokines IL-17A and IL-17F. This may represent a novel approach to therapy of Th17-mediated diseases by elevating soluble IL-23R while simultaneously reducing the remaining cell surface receptor density.