Cytokine promoter polymorphisms in Taiwanese patients with Graves' disease

Associations between gut microbiota and thyroidal function status in Chinese patients with Graves' disease

OBJECTIVE

The imbalance of gut microbiota has been linked to manifold endocrine diseases, but the association with Graves' disease (GD) is still unclear. The purpose of this study was to investigate the correlation between human gut microbiota and clinical characteristics and thyroidal functional status of GD.

METHODS

14 healthy volunteers (CG) and 15 patients with primary GD (HG) were recruited as subjects. 16SrDNA high-throughput sequencing was performed on IlluminaMiSeq platform to analyze the characteristics of gut microbiota in patients with GD. Among them, the thyroid function of 13 patients basically recovered after treatment with anti-thyroid drugs (oral administration of Methimazole for 3-5 months). The fecal samples of patients after treatment (TG) were sequenced again, to further explore and investigate the potential relationship between dysbacteriosis and GD.

RESULTS

In terms of alpha diversity index, the observed OTUs, Simpson and Shannon indices of gut microbiota in patients with GD were significantly lower than those in healthy volunteers (P < 0.05).The difference of bacteria species was mainly reflected in the genus level, in which the relative abundance of Lactobacillus, Veillonella and Streptococcus increased significantly in GD. After the improvement of thyroid function, a significant reduction at the genus level were Blautia, Corynebacter, Ruminococcus and Streptococcus, while Phascolarctobacterium increased significantly (P < 0.05). According to Spearman correlation analysis, the correlation between the level of thyrotropin receptor antibody (TRAb) and the relative abundance of Lactobacillus and Ruminococcus was positive, while Synergistetes and Phascolarctobacterium showed a negative correlation with TRAb. Besides, there were highly significant negative correlation between Synergistetes and clinical variables of TRAb, TPOAb and TGAb (P < 0.05, R <  - 0.6).

CONCLUSIONS

This study revealed that functional status and TRAb level in GD were associated with composition and biological function in the gut microbiota, with Synergistetes and Phascolarctobacterium protecting the thyroid probably, while Ruminococcus and Lactobacillus may be novel biomarkers of GD.

Gene polymorphisms of pro-inflammatory cytokines may affect the risk of Graves' disease: a meta-analysis

PURPOSE

Gene polymorphisms of pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1) and interleukin-6 (IL-6) may influence the risk of Graves' disease, but the results of so far published studies remain inconclusive. Therefore, the authors conducted this meta-analysis to assess relationships between TNF-α/IL-1/IL-6 polymorphisms and the risk of Graves' disease by pooling the findings of all relevant studies.

METHODS

A comprehensive literature searching of Pubmed, Embase, Web of Science and CNKI was conducted by the authors, and twenty-eight studies were found to be eligible for pooled analyses.

RESULTS

The pooled meta-analyses results showed that genotypic frequencies of TNF-α rs1800629, IL-1A rs1800587, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms among patients with Graves' disease and control subjects differed significantly. Moreover, we found that genotypic frequencies of TNF-α rs1800629 and IL-6 rs1800795 polymorphisms among patients with Graves' disease and control subjects in Caucasians differed significantly, and genotypic frequencies of IL-1A rs1800587, IL-1B rs16944, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms among patients with Graves' disease and control subjects in Asians also differed significantly. Nevertheless, we did not detect such genotypic frequencies differences for TNF-α rs361525 and IL-1B rs1143627 polymorphisms.

CONCLUSIONS

This meta-analysis suggests that TNF-α rs1800629, IL-1A rs1800587, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms may influence the risk of Graves' disease in overall population. Moreover, TNF-α rs1800629 and IL-6 rs1800795 polymorphisms may influence the risk of Graves' disease in Caucasians, while IL-1A rs1800587, IL-1B rs16944, IL-6 rs1800795 and IL-6 rs1800796 polymorphisms may influence the risk of Graves' disease in Asians.

Association of TNF-α promoter polymorphism and Graves' disease: an updated systematic review and meta-analysis

Graves' disease (GD) is a common autoimmune disorder with a genetic predisposition. Owing to the biological effect of tumor necrosis factor-α (TNF-α) on the thyroid gland and its gene location, TNF-α should be able to influence an individual's susceptibility to GD. In the present study, we conduct a meta-analysis of rs1800629 and rs361525 in TNF-α gene from all eligible case-control studies to assess the associations amongst reported TNF-α gene with GD. A total of ten case-control studies involving 2790 GD patients and 3472 healthy controls were included. The results showed that a significant association was characterized between the rs1800629 polymorphism and GD in the homozygous model (AA compared with GG: odds ratio (OR) = 1.97, 95% confidence interval (CI) = 1.27-3.06, P=0.002) and recessive model (AA compared with GA + GG: OR = 1.62, 95% CI = 1.04-2.50, P=0.03). GD susceptibility was significantly detected in European population in all genetic models after ethnicity stratification. In sharp contrast, no significant association could be detected in Asian population. Next, we conducted a meta-analysis for another promoter SNP rs361525. However, SNP rs361525 did not show a significant association with GD in any genetic model before and after ethnicity stratification. Together, our data support that only the promoter single-nucleotide polymorphism (SNP) rs1800629 within the TNF-α gene is associated with increased risk for developing GD, especially in European population. Future large-scale studies are required to validate the associations between TNF-α gene and GD.

Association between polymorphism within interleukin related genes and Graves' disease: a meta-analysis of 22 case-control studies

Graves' disease (GD) is a common autoimmune disorder with a genetic predisposition. There is strong evidence to suggest that both Th1 and Th2 circulating cytokines are involved in the development of GD. In this study, we conducted a meta-analysis to assess the impact of seven variations of five IL-related genes on the susceptibility to GD. A total of 22 case-control studies involving 5338 GD patients and 6446 healthy controls were included. The results showed that only one SNP rs1800795 in IL-6 was significantly associated with GD in homozygous model (CC vs. GG: OR = 2.714, 95% CI = 1.047-7.039, p = 0.04), heterozygous model (CG vs. GG: OR = 1.295, 95% CI = 1.013-1.655, p = 0.039), dominant model (CC+CG vs. GG: OR = 1.418, 95% CI = 1.122-1.793, p = 0.003) and additive model (C vs. G: OR = 1.432, 95% CI = 1.087-1.886, p = 0.011).To explain the heterogeneity, we performed the subgroup analysis by ethnicity. The ethnicity stratification revealed that the association between rs1800795 and GD tended to be much stronger for Asian than European population in homozygous, dominant, recessive, and additive models. The remaining 6 SNPs in 4 genes did not show any significant association with GD in any genetic models. Together, our data support that rs1800795 within the IL-6 gene confers genetic susceptibility for GD. Future large-scale studies are required to validate the associations between IL-6 and others IL-related genes and GD.

Association of Interleukin 10 Gene Polymorphisms with Autoimmune Thyroid Disease: Meta-Analysis

The aim of this study was to perform a meta-analysis of eligible studies and to derive a precise estimate of the association between interleukin 10 (IL10) polymorphisms and susceptibility to autoimmune thyroid disease (AITD). Meta-analyses were conducted on the associations between AITD and the -1082 G/A (rs1800896), -819 C/T (rs1800871) and -592 C/A (rs1800872) polymorphisms in IL10, and the haplotype of these polymorphisms and AITD. A total of 2903 AITD patients and 3060 controls in 10 eligible studies were included in the meta-analysis. This meta-analysis showed significant associations between IL10 at the -1082 G allele and overall AITD (OR: 1.44, 95% CI 1.13-1.82, P = 0.003), but no association between the IL10 -592 C allele and the -819 C allele and AITD. Subgroup studies demonstrated significant associations between the -1082 G allele and susceptibility to Graves' disease. Ethnicity-specific meta-analysis revealed significant associations between the -1082 G allele and AITD susceptibility in Asian populations; however, in Middle Eastern populations, no association was evident. Meta-analysis of the IL10 haplotype revealed an association between the ATA haplotype and AITD (OR: 1.17, 95% CI 1.00-1.36, P = 0.04). Meta-analysis demonstrates that the IL10 polymorphisms are associated with susceptibility to AITD.

Polymorphism of IL37 gene as a protective factor for autoimmune thyroid disease

Autoimmune thyroid disease (AITD) comprises Graves' disease (GD) and Hashimoto's thyroiditis (HT). IL37 has been recently proved to be a natural suppressor for innate immunity and acquired immunity. Therefore, this study was conducted to identify the association of IL37 genetic polymorphisms with AITD in Chinese Han population. Polymorphisms of rs3811046/rs3811047/rs2723176/rs272186 in the IL37 gene were assessed in a case-control study comprising 701 GD patients, 301 HT patients and 939 controls. Genetic variants were genotyped by multiplex polymerase chain reaction and ligase detection reaction. The frequencies of the minor allele A of rs2723176 and A of rs2723186 were significantly lower in the GD patients than in the controls (P=0.014, OR=0.774; P=0.014, OR=0.777). After gender stratification, the rs3811046 G allele and the rs3811047/rs2723186 A allele were both significantly associated with a decreased risk of GD in female patients (P=0.030, OR=0.777; P=0.023, OR=0.774; P=0.029, OR=0.761). However, none of the four single nucleotide polymorphisms of IL37 gene showed any significant association with HT. Moreover, haplotype analysis revealed the GCG haplotype conferred increased risk for GD as a whole and in female GD patients (OR=1.213; OR=1.320). The ACG haplotype was associated with an increased risk of HT as a whole (OR=1.567) and in male GD patients (OR=1.820). In contrast, the AAA haplotype showed a protective role for GD as a whole (OR=0.760) and in female GD patients (OR=0.765). Our study strongly supports that the IL37 gene variants are associated with the susceptibility to AITD.

Genetic variants of interleukin-4 gene in autoimmune thyroid diseases: an updated meta-analysis

Autoimmune thyroid diseases (AITDs) including Graves' disease (GD) and Hashimoto's thyroiditis (HT) are common autoimmune endocrine disorders. Interleukin-4 (IL-4), a cytokine secreted by T cells, plays a critical role in antigen-specific Th2 responses. The IL-4 gene is highly polymorphic and it has been reported that the polymorphism at -590 (T/C, rs2243250) in the promoter region of IL-4 may contribute to the development of AITDs. Recently, several case-control studies have examined the association of genetic variants of IL-4 with AITDs. However, the results of these studies remain conflicting. To systematically study the role of IL-4 in the pathogenesis of AITDs, we conducted a meta-analysis including 11 eligible studies (1847 cases and 2068 healthy controls). Fixed-effect or random-effect models were used to calculate pooled odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Our results revealed a significant association between the IL-4 genetic variant (-590, T/C, rs2243250) and the risk of developing AITDs (TC + TT versus TT genotype: OR = 1.83, 95% CI = 1.083-3.091, p = 0.024). These findings demonstrate that the IL-4 rs2243250 genetic variant might play a key role in the development of AITDs.

Increased expression of IL-37 in patients with Graves' disease and its contribution to suppression of proinflammatory cytokines production in peripheral blood mononuclear cells

Background

Intreleukin-37 (IL-37), a member of IL-1 family, is primarily an anti-inflammatory cytokine, which reduces systemic and local inflammation. However, the expression and role of IL-37 in Graves' disease (GD) remains unknown. This study aims to measure the levels of serum and peripheral blood mononuclear cells (PBMCs) IL-37 in patients with Graves' disease and to examine its association with disease activity. Furthermore, we investigate the effect of IL-37 on proinflammatory cytokines involved in the pathogenesis of GD.

Methods

The expressions of IL-37, TNF-α, IL-6, and IL-17 mRNA in peripheral blood mononuclear cells (PBMCs) of 40 patients with Graves' disease were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR), and the levels of IL-37, TNF-α, IL-6, and IL-17 in serum were detected by enzyme-linked immunoassay (ELISA). The correlation of serum IL-37 levels with cytokines and disease activity in Graves' disease patients were investigated. The expressions of cytokines TNF-α, IL-6, and IL-17 in PBMCs under recombinant IL-37 stimulation were determined by RT-PCR and ELISA respectively.

Results

The levels of IL-37, TNF-α, IL-6, and IL-17 in PBMCs and serum were significantly increased in patients with GD compared with healthy controls (HC). Serum IL-37 were closely correlated with TNF-α, IL-6, IL-17, thyrotropin (TSH), free thyroxine (FT4),free triiodothyronine (FT3) and thyrotropin receptor antibody (TRAB). GD patients with active disease showed higher IL-37 mRNA and serum protein levels compared with those with inactive disease as well as HC. Moreover, IL-37 suppressed the production of IL-6, IL-17 and TNF-α in PBMCs of patients with GD.

Conclusions

Increased level of IL-37 in patients with GD are associated with TNF-α, IL-6, IL-17 and disease activity, and it plays a protective role against inflammatory effect in GD by inhibiting the production of proinflammatory cytokines. Thus, IL-37 may provide a novel research target for the pathogenesis and therapy of GD.

Polymorphisms in the TNFA and IL6 genes represent risk factors for autoimmune thyroid disease

BACKGROUND

Autoimmune thyroid disease (AITD) comprises diseases including Hashimoto's thyroiditis and Graves' disease, both characterized by reactivity to autoantigens causing, respectively, inflammatory destruction and autoimmune stimulation of the thyroid-stimulating hormone receptor. AITD is the most common thyroid disease and the leading form of autoimmune disease in women. Cytokines are key regulators of the immune and inflammatory responses; therefore, genetic variants at cytokine-encoding genes are potential risk factors for AITD.

METHODS

Polymorphisms in the IL6-174 G/C (rs1800795), TNFA-308 G/A (rs1800629), IL1B-511 C/T (rs16944), and IFNGR1-56 T/C (rs2234711) genes were assessed in a case-control study comprising 420 Hashimoto's thyroiditis patients, 111 Graves' disease patients and 735 unrelated controls from Portugal. Genetic variants were discriminated by real-time PCR using TaqMan SNP genotyping assays.

RESULTS

A significant association was found between the allele A in TNFA-308 G/A and Hashimoto's thyroiditis, both in the dominant (OR = 1.82, CI = 1.37-2.43, p-value = 4.4×10(-5)) and log-additive (OR = 1.64, CI = 1.28-2.10, p-value = 8.2×10(-5)) models. The allele C in IL6-174 G/C is also associated with Hashimoto's thyroiditis, however, only retained significance after multiple testing correction in the log-additive model (OR = 1.28, CI = 1.06-1.54, p-value = 8.9×10(-3)). The group with Graves' disease also registered a higher frequency of the allele A in TNFA-308 G/A compared with controls both in the dominant (OR = 1.85, CI = 1.19-2.87, p-value = 7.0×10(-3)) and log-additive (OR = 1.69, CI = 1.17-2.44, p-value = 6.6×10(-3)) models. The risk for Hashimoto's thyroiditis and Graves' disease increases with the number of risk alleles (OR for two risk alleles is, respectively, 2.27 and 2.59).

CONCLUSIONS

This study reports significant associations of genetic variants in TNFA and IL6 with the risk for AITD, highlighting the relevance of polymorphisms in inflammation-related genes in the etiopathogenesis of AITD.

Relationship between the IL-4 gene promoter -590C/T (rs2243250) polymorphism and susceptibility to autoimmune diseases: a meta-analysis

OBJECTIVE

Studies investigating the association between interleukin (IL)-4 gene promoter -590C/T (rs2243250) polymorphism and autoimmune diseases report conflicting results. To derive a more precise estimation of the relationship, a meta-analysis was performed.

METHODS

A systematic literature search was conducted to identify relevant studies. Pooled odds ratio (OR) with 95% confidence interval (CI) was used to estimate the strength of association.

RESULTS

A total of 6001 cases and 6788 controls from 24 studies were analysed. Significant association of the C allele of IL-4 rs2243250 polymorphism with rheumatoid arthritis (RA) was detected (odds ratio (OR) = 0.696, 95% confidence interval (CI) = 0.601-0.807). Stratification by ethnicity indicated an association between the IL-4 rs2243250 polymorphism and RA in Caucasians. Furthermore, the overall ORs of the associations between the C allele and multiple scleorosis (MS) were 1.340 (95% CI = 1.102-1.630). However, we failed to reveal any association between IL-4 rs2243250 polymorphism and systemic lupus erythematosus (SLE), type 1 diabetes (T1D) or Graves' disease (GD).

CONCLUSIONS

The present study suggests that the IL-4 rs2243250 polymorphism might be associated with genetic susceptibility to autoimmune diseases, including RA and MS.

Probiotic Lactobacillus reuteri alleviates the response to gastric distension in rats

Probiotic lactic acid bacteria have been reported to alleviate symptoms in patients with irritable bowel syndrome. However, they have not been tested for use in functional gastric disease. We therefore investigated if strains previously shown to protect from response to colorectal distension (CRD) in rats also modulate response to gastric distension (GD). Healthy, male Sprague-Dawley rats were treated with viable, heat-killed, gamma-irradiated Lactobacillus reuteri or viable Lactobacillus plantarum wild type (WT), L. plantarum Dlt¯mutant, conditioned medium or medium control (9 d), and subjected to GD under anesthesia using an i.g. Teflon catheter. Effects were measured by heart rate (HR) changes during noxious distension (60 mm Hg) compared to baseline HR values. We also investigated the localization of viable, green fluorescent protein-transfected bacteria in the stomach mucosa. Viable L. reuteri decreased the bradycardia induced by noxious GD compared to placebo controls (P < 0.001). Heat-killed or gamma-irradiated L. reuteri and conditioned medium did not have a protective effect in GD. Viable L. plantarum WT and Dlt¯mutant, previously shown to be effective antinociceptive agents in CRD, showed no protective effect in GD. All viable bacteria were associated with the pars glandularis of the rat stomach. Thus, we conclude that the antinociceptive mechanisms of action of probiotic bacteria differ between the stomach and the colon. Symptom alleviation cannot be attributed to the localization of the bacteria in the stomach. Information derived from effects of CRD cannot be extrapolated to effects in the stomach, which are likely to be strain and organ specific.

An association of interleukin-10 gene polymorphisms with Graves' disease in two Chinese populations

Graves' disease (GD) is a common autoimmune disorder with a genetic predisposition. The cytokine interleukin-10 (IL-10) has a central role in mediating inflammation, which may affect the outcome of the patients with GD. To elucidate the impact of IL-10 gene polymorphisms, we performed a two-stage case-control association study of five single-nucleotide polymorphisms (SNPs) within the IL-10 gene as well as a meta-analysis of two SNP's rs1800896 and rs1800872 covering three previous studies from Iran, Taiwan, and the United Kingdom. The five SNPs were genotyped by SNPstream Genotyping and Taqman PCR. There was a significant increase of G allele of rs1800896 in the two cohorts (P (allele) = 2.6 × 10(-4) and 0.0082 for cohort Shanghai and Xiamen, respectively) compared with the controls. The meta-analysis showed the risk-increasing effects for the G allele of rs1800896 in GD (OR = 1.88; P < 0.00001). The allele and haplotype analysis results suggested that the polymorphisms of IL-10 were associated with GD susceptibility in the Chinese population.

Genetic susceptibility to Graves' ophthalmopathy: The role of polymorphisms in anti-inflammatory cytokine genes

BACKGROUND

Various polymorphisms occur in cytokine genes involved in inflammatory processes in Graves' ophthalmopathy (GO). Anti-inflammatory cytokines such as transforming growth factor- β (TGF-β), interleukin-10 (IL-10) and interleukin-4 (IL-4) are among those believed to be involved in the disease process. In this study, we investigated the association between 8 polymorphisms within the mentioned cytokines and GO.

METHODS

The following polymorphisms were studied in 50 patients with GO, 57 Graves' patients without GO and 140 healthy individuals using polymerase chain reaction with sequence-specific primers: TGF-β (+869C/T, +915G/C), IL-10 (-1082A/G, -819C/T, -592C/A) and IL-4 (-1098T/G, -590T/C, -33C/T). A corrected p value less than 0.05 was considered statistically significant.

RESULTS

The TGF-β +915C allele (Odds Ratio [OR] = 2.20) and CC genotype (OR = 7.50) as well as +869C allele (OR = 2.21) showed significant correlations with GO. Regarding IL-4 polymorphisms, the -1098G allele (OR = 2.09) and GG genotype (OR = 7.49), and the -33T allele (OR = 2.05) and TT genotype (OR = 4.00) were significantly associated with GO. The IL-10 -819TT genotype (OR = 5.00) was significantly correlated with GO.

CONCLUSION

This is the first study to show that polymorphisms in anti-inflammatory cytokine genes are associated with susceptibility to GO.

Association of interleukin-4 promoter polymorphisms in Taiwanese patients with type 2 diabetes mellitus

Many factors have been implicated in the onset of type 2 diabetes mellitus (T2DM). Recently, immune response and inflammation were suggested to play certain roles in the development and complications of T2DM. The aim of this study is to investigate the putative correlation between the promoter polymorphisms of interleukin-4 (IL-4), one of the immune-regulatory type 2 helper T-cell cytokines, and T2DM. Genomic DNA from 425 Taiwanese T2DM patients and 148 nondiabetic control study subjects were extracted, and their IL-4 promoter polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism. Both of the distribution of IL-4 C-589T (P = .013) and C-34T (P = .05) genotypes were significantly different between T2DM patients and control subjects. Significant association between IL-4 C-589T alleles (P = .002) and T2DM, as well as C-34T alleles and T2DM (P =.024), was also identified. In addition, a statistically significant association between homologous IL-4 -589 C/C genotype and lower circulatory high-density lipoprotein cholesterol levels was observed. Our results suggested that IL-4 promoter polymorphisms are associated with T2DM. A significant association between IL-4 -589 C/C genotype and lower circulatory high-density lipoprotein cholesterol level was observed as well. The above results suggested that IL-4 may participate in lipid metabolism and diabetic susceptibility.

Graves' disease and gene polymorphism of TNF-α, IL-2, IL-6, IL-12, and IFN-γ

The role of genetic factors in the pathogenesis of Graves' disease (GD) is not clear. The purpose of this study was to investigate the association between single nucleotide polymorphisms in pro-inflammatory cytokine genes and GD in Iranian patients. A case-control hospital-based study was carried out on 107 GD patients and 140 healthy controls. Cytokine typing was performed by polymerase chain reaction with sequence-specific primers (PCR-SSP) assay. The allele and genotype frequencies of the following cytokine genes were determined: TNF-α (-308A/G, -238A/G), IL-2 (-330T/G, +166G/T), IL-6 (-174C/G, A/G nt565), IL-12 (-1188A/C), and IFN-γ (UTR 5644A/T). The following alleles and genotypes were significantly overrepresented in patients: TNF-α -308A allele (P < 0.01) and AA genotype (P < 0.05), IL-2 -330G allele (P < 0.01) and GG genotype (P < 0.01), IL-6 -174C allele (P < 0.01) and CC genotype (P < 0.01), IL-12 -1188C allele (P < 0.01) and CC genotype (P < 0.01), IFN-γ UTR5644T allele (P < 0.01) and TT genotype (P < 0.01). In conclusion, this is the first study to show a significant association between GD and IL-2 -330G, IL-12 -1188C, and IFN-γ UTR 5644T alleles. Our results support the hypothesis that polymorphism in pro-inflammatory cytokines might be involved in predisposition to GD.

Polymorphisms of cytotoxic T lymphocyte-associated antigen-4 and cytokine genes in Taiwanese patients with ankylosing spondylitis

Cytokines, costimulatory and counter-regulatory molecules play important roles in the regulation of inflammatory response, and are good candidates involved in the development of ankylosing spondylitis (AS). This study investigated the genotypic distribution of proinflammatory cytokines and T-cell negative regulator cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) in healthy subjects and AS patients. Genomic DNA was extracted from 143 AS patients and 166 ethnic-matched healthy subjects. Nine polymorphisms within the genes of interleukin-4 (IL-4) (-34T>C, -81A>G, -285C>T and -589T>C), interleukin-6 (IL-6) (-174G>C), interleukin-10 (IL-10) (-592A>C and -819T>C) and CTLA-4 (-318C>T and +49A>G) were examined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. Significantly less AS patients carried the CTLA-4 high-expressing -318 T allele (P = 0.040). The CTLA-4 +49A>G genotypes were associated with circulatory levels of the inflammatory marker C-reactive protein (CRP) (P = 0.022). Our study documented the most complete genetic information of Taiwanese AS patients. The observations that CTLA-4 +49A>G genotypes are associated with circulatory CRP levels and significantly less AS subjects carrying CTLA-4 higher-secretor -318 T allele suggest the level and regulation of inflammation in AS subjects may be pre-determined by and associated with CTLA-4 genotypes.

Gene polymorphisms of interleukin-4, interleukin-10 and transforming growth factor-beta in Graves' disease

Among genetic factors that may contribute to the development and progression of Graves' disease (GD) and its complications are polymorphisms in the genes encoding cytokines. The association between GD and the following polymorphisms in anti-inflammatory cytokines was studied in 107 patients with GD and 140 healthy controls: IL-4 (-1098T/G, -590T/C, -33C/T), IL-10 (-1082A/G, -819C/T, -592C/A) and TGF-beta (+869T/C, +915G/C). The following alleles and genotypes were significantly (P < 0.01 after correction for multiple testing) more frequent among patients: the IL-4 -1098G allele and GG genotype (OR = 3.12 and 105.00, respectively), IL-4 -33T allele and TT genotype (OR = 2.52 and 118.83, respectively), IL-10 -1082G allele and GG genotype (OR = 2.16 and 6.40, respectively), IL-10 -819T allele, TC and TT genotype (OR = 2.60, 3.68 and 6.76, respectively), IL-10 -592A allele, AC and AA genotype (OR = 2.41, 2.89 and 5.68, respectively), TGF-beta +869C allele and CC genotype (OR = 2.24 and 6.21, respectively), and TGF-beta +915C allele, CG and CC genotype (OR = 7.81, 11.80 and 20.40, respectively). The only allele and genotype with a lower frequency in patients were IL-4 -590T allele and TC genotype (OR = 0.47 and 0.08, respectively; P < 0.01). In conclusion, this study highlighted the importance of anti-inflammatory cytokine gene polymorphisms in susceptibility to GD.

Tumor necrosis factor alpha (TNF-alpha) polymorphisms in Chinese patients with Graves' disease

OBJECTIVES

Tumor necrosis factor alpha (TNF-alpha) may play a central role in the development of Graves' disease (GD). The aim of this study was to investigate the association of TNF-alpha polymorphisms with GD in Chinese population.

DESIGN AND METHODS

Genomic DNA was extracted from peripheral blood lymphocyte of 436 GD patients and 316 control subjects. TNF-alpha polymorphisms at positions -308 (G-308A, rs1800629), -238 (G-238A, rs361525), and +419 (G+419A, rs3093661) were genotyped.

RESULTS

The distribution of TNF-alpha -238 and +419 allelic frequencies between GD and control individuals was significantly different. Both the G alleles of TNF-alpha -238 (OR 2.385, 95%CI 1.359-4.184) and +419 (OR 2.293, 95%CI 1.303-4.035) SNPs conferred higher risk of GD as compared with A alleles. No significant difference of -308 allelic frequency was observed. Further haplotype analysis revealed that the haplotype GGG was associated with an increased risk of GD (OR 1.554, 95%CI 1.125-2.146), whereas the haplotype GAA was found to be protective (OR 0.419, 95%CI 0.239-0.736).

CONCLUSIONS

This study demonstrated the association of TNF-alpha gene with GD in Chinese patients.

Polymorphisms in the interleukin 3 gene show strong association with susceptibility to Graves' disease in Chinese population

Graves' disease (GD) is a common organ-specific autoimmune disorder, which is multifactorial and develops in genetically susceptible individuals. We had earlier mapped a susceptibility locus for GD to chromosome 5q31-33 in a linkage study. Here we used tag single-nucleotide polymorphisms (SNPs) to search for genetic variants associated with GD, and examined 19 functional candidate genes in this chromosomal region. We identified 192 polymorphisms by re-sequencing the candidate genes, and selected 51 tagSNPs to genotype in a case-control collection of 1118 south Han Chinese subjects (428 cases and 690 controls). Initial analysis suggested that a non-synonymous SNP rs40401 (P27S) of interleukin 3 (IL3) was associated with GD, and further fine-mapping showed that rs40401, or its perfect proxy SNP rs31480 in the 5' flanking region of IL3, fully accounted for the association signal at this locus. We replicated significant association of rs40401 with GD in an independent sample collection of 839 north Han Chinese subjects. A combined analysis revealed strong validation of this association (odds ratio (OR(common))=1.63, combined P (P(comb))=4 x 10(-6) in the Recessive disease model). This study provides convincing evidence that the IL3 gene is a susceptibility locus for GD in the Chinese population.

Is IL-10-819C/T gene polymorphism modulating the risk of gallbladder disease in north Indian population?

BACKGROUND

Gallbladder carcinoma (GBC) is a highly aggressive neoplasm that arises in the background of gall stones and inflammation. Anti-inflammatory cytokine interleukin-10 (IL-10) gene polymorphisms have been associated with susceptibility to various inflammatory diseases and cancers.

AIM

of the study The aim of the present study was to investigate whether IL-10-819C/T polymorphism is associated with GBC susceptibility.

METHODS

The study subjects comprised 124 GBC patients, 135 patients with symptomatic gallstone disease, and 200 healthy subjects. Genomic DNA was extracted from blood leukocytes and IL-10-819C/T gene polymorphism was analyzed by polymerase chain reaction-restriction fragment length polymorphism.

RESULTS

Frequency distributions of IL-10-819C/T genotypes were similar in GBC, gallstone patients, and healthy subjects. However, after stratification on the basis of sex, in male GBC patients, the TT genotype of IL-10-819C/T polymorphism showed an approximately sevenfold risk (p value = 0.038; odds ratio = 6.58; 95% confidence interval = 1.11-39.11) in the presence of gall stones when compared with gallstone patients.

CONCLUSION

These results suggest that interplay of sex hormones and IL-10-819C/T polymorphism may lead to the susceptibility of gallstone-mediated gallbladder carcinogenesis.

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.

Cytokines, Graves' disease, and thyroid-associated ophthalmopathy

Graves' disease, an autoimmune process associated with thyroid dysfunction, can also manifest as remodeling of orbital connective tissue. Affected tissues exhibit immune responses that appear to be orchestrated by resident cells and those recruited from the bone marrow through their expression and release of cytokines and surface display of cytokine receptors. Cytokines are small molecules produced by many types of cells, including those of the "professional" immune system. Aberrant cytokine expression appears to play an important role in the pathogenesis of many human diseases, including thyroid autoimmunity. The skewed pattern of cytokine expression in the thyroid, including the T helper cell bias, may condition the response to apoptotic signals and determine the characteristics of an autoimmune reaction. Furthermore, chemoattractant cytokines, including IL16, RANTES, and CXCL10, elaborated by resident cells in the thyroid and orbit may provoke mononuclear cell infiltration. Other cytokines may drive cell activation and tissue remodeling. Thus cytokines and the signaling pathways they activate represent attractive therapeutic targets. Interruption of these might alter the natural course of Graves' disease and its orbital manifestations.

Genetic association of IL-10 gene promoter polymorphism and HIV-1 infection in North Indians

INTRODUCTION

Cytokines play a significant role in host immune defense. IL-10 is an anti-inflammatory, immunomodulatory cytokine that can both stimulate and suppress the immune response and inhibits HIV-1 replication in vivo. Interindividual variations in IL-10 production were genetically contributed to polymorphisms within IL-10 promoter region.

AIMS

The aim of this study was to investigate the association of IL-10 gene promoter -1082 G/A, -819 C/T, and 592 C/A polymorphism on HIV-1 transmission /progression in North Indian individuals.

PATIENTS AND METHODS

A total of 180 HIV-1 seropositive (HSP) stratified on the basis of disease severity (stage I, II, and III), 50 HIV-1 exposed seronegative (HES) and 305 HIV-1 seronegative (HSN) individuals were genotyped for IL-10 gene promoter by polymerase chain reaction-restriction fragment length polymorphism. A suggestive evidence of association was obtained for IL-10 592 C/A promoter polymorphism at the level of allele and genotype distribution. The frequency of IL-10 592 A allele and genotype was significantly increased in HSP compared to HSN (p = 0.013; OR = 1.412 and p = 0.034; OR = 1.685 respectively). Further comparison in between different clinical stages of HIV-1 infected patients of IL-10 592 A allele and genotype revealed a significant increase in its frequency in the stage III compared with those together in stage I (p = 0.004, OR = 2.181 and p = 0.002, OR = 4.156, respectively). This study reports for the first time that IL-10 gene promoter 592 C/A polymorphism may be a risk factor for HIV-1 transmission/progression in HIV-1 infected North Indian individuals.

Association of tumour necrosis factor alpha (TNF-alpha) polymorphisms with Graves' disease: A meta-analysis

OBJECTIVE

To quantitatively summarize the association between tumour necrosis factor alpha (TNF-alpha) gene polymorphisms and Graves' disease.

DESIGN AND METHODS

Relevant studies were identified from the following electronic databases: Cochrane Library, MEDLINE, EMBASE and Chinese Bio-medicine Database. A meta-analysis of relevant studies was performed.

RESULTS

This meta-analysis included 10 case-control studies, which included 2271 Graves' disease cases and 2633 controls. The combined results based on all studies showed that there was significant difference in genotype distribution (-308A/G; -308G/G; -863C/C; -863C/A; -1031C/T) between Graves' disease and controls. When stratifying for race, statistically significant results were observed in three genotype distribution (-863C/C; -863C/A; -1031C/T) between Graves' disease and controls among Asians. Statistically significant results were observed in only two genotype distribution (-308A/G; -308G/G) between Graves' disease and controls among Caucasians.

CONCLUSIONS

This meta-analysis suggests that TNF-alpha gene polymorphisms at positions -308 (G-308A), -863 (C-863A), and -1031 (T-1031C) were associated with Graves' disease.