Functional polymorphisms affecting Th1 differentiation are associated with the severity of autoimmune thyroid diseases

Causal relationship between inflammatory cytokines and autoimmune thyroid disease: a bidirectional two-sample Mendelian randomization analysis

Background

Autoimmune thyroid disease (AITD) ranks among the most prevalent thyroid diseases, with inflammatory cytokines playing a decisive role in its pathophysiological process. However, the causal relationship between the inflammatory cytokines and AITD remains elusive.

Methods

A two-sample Mendelian randomization (MR) analysis was performed to elucidate the causal connection between AITD and 41 inflammatory cytokines. Genetic variations associated with inflammatory cytokines were sourced from the FinnGen biobank, whereas a comprehensive meta-analysis of genome-wide association studies (GWASs) yielded data on Graves' disease (GD) and Hashimoto thyroiditis. Regarding the MR analysis, the inverse variance-weighted, MR-Egger, and weighted median methods were utilized. Additionally, sensitivity analysis was conducted using MR-Egger regression, MR-pleiotropy residual sum, and outliers.

Results

Seven causal associations were identified between inflammatory cytokines and AITD. High levels of tumor necrosis factor-β and low levels of stem cell growth factor-β were indicative of a higher risk of GD. In contrast, high levels of interleukin-12p70 (IL-12p70), IL-13, and interferon-γ and low levels of monocyte chemotactic protein-1 (MCP-1) and TNF-α suggested a higher risk of HD. Moreover, 14 causal associations were detected between AITD and inflammatory cytokines. GD increases the levels of macrophage inflammatory protein-1β, MCP-1, monokine induced by interferon-γ (MIG), interferon γ-induced protein 10 (IP-10), stromal cell-derived factor-1α, platelet-derived growth factor BB, β-nerve growth factor, IL-2ra, IL-4, and IL-17 in blood, whereas HD increases the levels of MIG, IL-2ra, IP-10, and IL-16 levels.

Conclusion

Our bidirectional MR analysis revealed a causal relationship between inflammatory cytokines and AITD. These findings offer valuable insights into the pathophysiological mechanisms underlying AITD.

Mechanism Study on Chinese Medicine in Treatment of Nodular Goiter

Nodular goiter has become increasingly prevalent in recent years. Clinically, there has been a burgeoning interest in nodular goiter due to the risk of progression to thyroid cancer. This review aims to provide a comprehensive summary of the mechanisms underlying the therapeutic effect of Chinese medicine (CM) in nodular goiter. Articles were systematically retrieved from databases, including PubMed, Web of Science and China National Knowledge Infrastructure. New evidence showed that CM exhibited multi-pathway and multi-target characteristics in the treatment of nodular goiter, involving hypothalamus-pituitary-thyroid axis, oxidative stress, blood rheology, cell proliferation, apoptosis, and autophagy, especially inhibition of cell proliferation and promotion of cell apoptosis, involving multiple signal pathways and a variety of cytokines. This review provides a scientific basis for the therapeutic use of CM against nodular goiter. Nonetheless, future studies are warranted to identify more regulatory genes and pathways to provide new approaches for the treatment of nodular goiter.

LncRNA RUNX1-IT1 affects the differentiation of Th1 cells by regulating NrCAM transcription in Graves' disease

Graves' disease (GD) is a kind of autoimmune diseases. The development of GD is closely related to the imbalance of Th1/Th2 generated by the differentiation of CD4⁺ T cells. This study was sought to clarify the role of lncRNA RUNX1-IT1 and explore the mechanism of its function. The expressions of RUNX1-IT1 and Neural cell adhesion molecule (NrCAM) in the peripheral blood of GD patients were detected by qRT-PCR and Western blot. We performed RNA pull down, RIP, and ChIP experiments to verify the correlation between p53 and RUNX1-IT1, p53 and NrCAM. The levels of Th1 cells differentiation markers were detected by Flow cytometry assay and ELISA. The expressions of lncRNA RUNX1-IT1 and NrCAM were most significantly up-regulated in CD4⁺ T cells of GD patients, and NrCAM expression was significantly positively correlated with RUNX1-IT1 expression. Furthermore, p53 was a potential transcription factor of NrCAM, which could interact with NrCAM. NrCAM level was up-regulated after the overexpression of p53 in CD4⁺ T cells, while knockdown of RUNX1-IT1 reversed this effect. Down-regulation of NrCAM and RUNX1-IT1 could decrease the mRNA and protein levels of transcriptional regulator T-bet and CXC chemokine ligand 10 (CXCL10) in CD4⁺ T cells. Our results suggested that RUNX1-IT1 regulated the expressions of the important Th1 factor T-bet, CXCL10, and interferon γ (IFN-γ) by regulating NrCAM transcription, thus participating in the occurrence and development of specific autoimmune disease GD.

Polymorphisms in Vitamin A-Related Genes and Their Functions in Autoimmune Thyroid Disease

Background: Vitamin A is a factor that suppresses immune responses, including T helper (Th)1 and Th17 responses. However, there has been no report showing the association between vitamin A-related genes (CYP26B1, RARB, and RARG) and the prognosis of autoimmune thyroid disease (AITD). The objective of this study was to clarify the association between vitamin A-related genes and the susceptibility and prognosis of AITD. Methods: We genotyped polymorphisms in genes encoding vitamin A-related molecules using the polymerase chain reaction-restriction fragment length polymorphism method. The proportion of T helper cells was analyzed by flow cytometry. Serum interleukin (IL)-17 and interferon (IFN)-γ were examined by enzyme-linked immunosorbent assay. Results:CYP26B1 rs3768641 GG genotype and G allele were significantly more frequent in patients with mild Hashimoto's thyroiditis (HT) than in those with severe HT (p = 0.0013 and 0.0024, respectively). The RARB rs1997352 CC genotype was significantly more frequent in HT patients than in controls (p = 0.0207). The proportion of Th17 cells was significantly higher in CYP26B1 rs2241057 TT genotype than C carrier (CC+CT genotypes) (p = 0.0385), in RARB rs1997352 A carrier (AA+AC genotypes) than those with CC genotype (p = 0.0246), and in RARG rs7398676 G carrier (GG+GT genotypes) than in TT genotype (p = 0.0249). In the RARB rs1997352 polymorphism, HT patients with a high concentration of IFN-γ (≥150 ng/mL) were more frequent in the CC genotype than in A carriers (AA+AC genotypes) (p = 0.0226). Serum levels of IL-17 were significantly elevated in subjects with the TT genotype of the CYP26B1 rs2241057 single nucleotide polymorphism (SNP) (p = 0.0026) and in subjects with the GG genotype of the CYP26B1 rs3798641 SNP (p = 0.030). Subjects with a high concentration of IL-17 (≥0.71 pg/mL) were more frequent in RARG 7398676 G carriers (GG+GT genotypes) than in TT genotype (p = 0.0218). Conclusions: Polymorphisms in the CYP26B1 gene were related to the proportion of Th17 cells, the level of IL-17 and the severity of HT. Polymorphisms in RAR were related to the proportion of Th17 cells, concentrations of IFN-γ and IL-17, and susceptibility to HT.

Association between IL-18 gene polymorphisms and Hashimoto thyroiditis

BACKGROUND

Hashimoto's thyroiditis (HT), which is also called lymphocytic thyroiditis, is the most frequent autoimmune thyroid disease (AITD), in which T helper-1 lymphocytes mediate the disease. IL-18 is expressed in thyroid follicular cells (TFCs) during HT. The findings of studies aimed at investigating the relationship between IL-18 and HT are highly contradictory. In this study, we aimed to investigate the association between IL-18 gene polymorphisms and HT.

METHODS AND RESULTS

The study included 97 patients diagnosed with HT and 86 volunteers in the healthy control group. The IL18-607C/A (rs1946518) and -137G/C (rs187238) genotypes were determined using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. No significant difference in the mean age or sex was observed between the groups (p = 0.763 and p = 0.658, respectively). The -137 IL18 CG genotype was more frequent in HT patients than in controls. In HT patients, the risk of the IL-18 CG genotype was more than 2.237 times higher (OR 2.237%95 Cl 1.195-4.187, p = 0.039) than that of the G/G genotype. Additionally, the -607 AC genotype was more frequent in the control group than in the HT group (in individuals with the IL18 CG genotype).

CONCLUSIONS

According to our results, the CG genotype might be a risk factor for HT. Conversely, there is a possibility that the AC genotype plays a protective role against the condition. However, further studies will contribute to new solutions by revealing the molecular and cellular mechanisms of HT.

Association of cytokine Th2 gene polymorphisms with autoimmune thyroid diseases in Tunisian population

Autoimmune thyroid diseases (AITD) including Graves' disease (GD) and Hashimoto's thyroiditis (HT) are complex genetic diseases. Th2 cytokines act on the development of AITD. This study was conducted on Tunisian patients with AITD to investigate the association of Th2 cytokine gene polymorphisms and haplotype combination with GD or HT risk. A total of 156 controls, 160 patients with HT and 88 patients with GD were genotyped for IL-4 rs2243250, IL-5 rs2069812, IL-6 rs1800796 and IL-13 rs1800925 polymorphisms by PCR-RFLP. The AITD risk was assessed by a logistic regression analysis using the SNP stats statistical program. False-positive report probability (FPRP) was estimated to evaluate significant findings. IL-13 rs1800925 was associated with GD, after adjustment for age and gender, in codominant, dominant and allele genetic models (p = .0072; p = .0018; p = .012, respectively). Significant association of the IL-6 rs1800796C/G genotype with GD was also detected (p = .025). Furthermore, increased risk of HT was still found for IL-13 rs1800925T allele (p = .039, OR = 1.39) and for IL-4 rs2243250T/T genotype both in codominant (p = .033, OR = 2.59) and recessive (p = .011, OR = 2.73) models after adjustment for age and gender. Interestingly, haplotype analysis performed on the IL-4, IL-5 and IL-13 genes revealed a high risk of HT with CTT haplotype (p = .008, OR = 2.12). However, the CCT haplotype is a protective factor (OR = 0.36). Patients carrying the CT haplotype with only one minor allele had a moderate risk of HT (OR = 1.56). The FPRP analysis showed that the association of IL-13 rs1800925 polymorphism with GD and HT and the association of CTT haplotype with HT were noteworthy. In conclusion, the IL-4, IL-5, IL-6 and IL-13 polymorphism may play a role in susceptibility to GD and HT in the Tunisian population. Furthermore, gene-gene interaction between the IL-4, IL-5 and IL-13 significantly increases the risk of AITD. Further studies with larger numbers of individuals are needed to confirm the results.

The exploration of Hashimoto's Thyroiditis related miscarriage for better treatment modalities

Hashimoto's thyroiditis (HT) is the most prevalent autoimmune thyroid disease (ATD) worldwide and is strongly associated with miscarriage and even recurrent miscarriage (RM). Moreover, with a deepening understanding, emerging evidence has shown that immune dysfunctions caused by HT conditions, including imbalanced subsets of CD4+ T-helper cells, B regulatory (Breg) cells, high expression levels of CD56dim natural killer (NK) cells, and cytokines, possibly play an important role in impairing maternal tolerance to the fetus. In recent years, unprecedented progress has been made in recognizing the specific changes in immune cells and molecules in patients with HT, which will be helpful in exploring the mechanism of HT-related miscarriage. Based on these findings, research investigating some potentially more effective treatments, such as selenium (Se), vitamin D3, and intravenous immunoglobulin (IVIG), has been well developed over the past few years. In this review, we highlight some of the latest advances in the possible immunological pathogenesis of HT-related miscarriage and focus on the efficacies of treatments that have been widely introduced to clinical trials or practice described in the most recent literature.

TIM-3 genetic variants and risk of Behçet disease in the Iranian population

BACKGROUND

Behçet disease is a prototypical systemic autoimmune disease, caused by a complex interplay between environmental and genetic factors. The transmembrane immunoglobulin and mucin domain-3 (TIM-3) is a distinct member of the TIM family that is preferentially expressed on Th1 cells and plays a role in Th1-mediated autoimmune or inflammatory diseases, such as Behçet disease.

OBJECTIVE

The aim of this study was to test the potential association between TIM-3 gene polymorphisms and Behçet disease.

METHODS

Two single-nucleotide polymorphisms of TIM-3 (rs9313439 and rs10515746) were genotyped in 212 patients with Behçet disease and 200 healthy controls. Typing of the polymorphisms was performed using multiplex PCR amplification.

RESULTS

There were no significant differences in allele and genotype frequencies between the Behçet disease patients and controls who were successfully genotyped. Similar results were also found after stratification by gender, age, or clinical features.

STUDY LIMITATIONS

Lack of studies on various racial or ethnic groups and small sample size.

CONCLUSION

This study failed to demonstrate any association between the tested TIM-3 polymorphisms and Behçet disease.

Constitutive Changes in Circulating Follicular Helper T Cells and Their Subsets in Patients with Graves' Disease

Background

Follicular helper T (Tfh) cells are critical for high-affinity antibody generation and B cell maturation and differentiation, which play important roles in autoimmune diseases. Graves' disease (GD) is one prototype of common organ-specific autoimmune thyroid diseases (AITD) characterized by autoreactive antibodies, suggesting a possible role for Tfh cells in the pathogenesis of GD. Our objective was to explore the role of circulating Tfh cell subsets and associated plasma cells (PCs) in patients with GD.

Methods

Thirty-six patients with GD and 20 healthy controls (HC) were enrolled in this study. The frequencies of circulating Tfh cell subsets and PCs were determined by flow cytometry, and plasma cytokines, including interleukin- (IL-) 21, IL-4, IL-17A, and interferon- (IFN-) γ, were measured using an enzyme-linked immunosorbent assay (ELISA). The mRNA expression of transcription factors (Bcl-6, T-bet, GATA-3, and RORγt) in peripheral blood mononuclear cells (PBMCs) was evaluated by real-time quantitative PCR. Results. Compared with HC, the frequencies of circulating CD4⁺CXCR5⁺CD45RA⁻Tfh (cTfh) cells with ICOS and PD-1 expression, the Tfh2 subset (CXCR3⁻CCR6⁻Tfh) cells, and PCs (CD19⁺CD27^highCD38^high) were significantly increased in the GD patients, but the frequencies of Tfh1 (CXCR3⁺CCR6⁻Tfh) and Tfh17 (CXCR3⁻CCR6⁺Tfh) subset cells among CD4⁺T cells were significantly decreased in GD patients. The plasma concentrations of IL-21, IL-4, and IL-17A were elevated in GD patients. Additionally, a positive correlation was found between the frequency of PD-1⁺Tfh cells (Tfh2 or PCs) and plasma IL-21 concentration (or serum TPO-Ab levels). The mRNA levels of transcription factors (GATA-3 and RORγt) were significantly increased, but T-bet and Bcl-6 mRNA expression was not obviously varied in PBMCs from GD patients. Interestingly, Tfh cell subsets and PCs from GD patients were partly normalized by treatment.

Conclusion

Circulating Tfh cell subsets and PCs might play an important role in the pathogenesis of GD, which are potential clues for GD patients' interventions.

TIM-3 rs1036199 polymorphism increases susceptibility to autoimmune diseases: evidence based on 4200 subjects

Conflicting results have been reported regarding differing studies on the association between T-cell immunoglobulin and mucin domain 3 polymorphisms and autoimmune disease. The purpose of the present study was to evaluate the association of TIM-3 rs1036199 (4259 G/T) polymorphism with autoimmune disease susceptibility. A meta-analysis was performed to obtain a more precise evaluation of the association. Ten eligible studies were retrieved by searching PubMed, Embase and Web of Science databases, and statistical analyses were performed using STATA software. The pooled results indicated that TIM-3 rs1036199 polymorphism was significantly associated with an increased risk of overall autoimmune disease in allele comparison (G versus T: OR = 1.59, 95%CI: 1.17-2.17) and heterozygous comparison (GT versus TT: OR = 1.68, 95%CI: 1.37-2.06). Subgroup analyses based on disease type demonstrated that TIM-3 rs1036199 polymorphism was associated with an increased risk of rheumatic arthritis (G versus T: OR = 1.88, 95%CI: 1.45-2.44; GT versus TT: OR = 2.02, 95%CI: 1.53-2.65), especially in Asian populations.