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

Association of cytokine gene polymorphisms with peripheral neuropathy susceptibility in people living with HIV in Greece

Relatively little research has been done in recent years to understand what leads to the unceasingly high rates of HIV sensory neuropathy despite successful antiretroviral treatment. In vivo and in vitro studies demonstrate neuronal damage induced by HIV and increasingly identified ART neurotoxicity involving mitochondrial dysfunction and innate immune system activation in peripheral nerves, ultimately all pathways resulting in enhanced pro-inflammatory cytokine secretion. Furthermore, many infectious/autoimmune/malignant diseases are influenced by the production-profile of pro-inflammatory and anti-inflammatory cytokines, due to inter-individual allelic polymorphism within cytokine gene regulatory regions. Associations of cytokine gene polymorphisms are investigated with the aim of identifying potential genetic markers for susceptibility to HIV peripheral neuropathy including ART-dependent toxic neuropathy. One hundred seventy-one people living with HIV in Northern Greece, divided into two sub-groups according to the presence/absence of peripheral neuropathy, were studied over a 5-year period. Diagnosis was based on the Brief Peripheral Neuropathy Screening. Cytokine genotyping was performed by sequence-specific primer-polymerase chain reaction. Present study findings identify age as an important risk factor (p < 0.01) and support the idea that cytokine gene polymorphisms are at least involved in HIV peripheral-neuropathy pathogenesis. Specifically, carriers of IL1a-889/rs1800587 TT genotype and IL4-1098/rs2243250 GG genotype disclosed greater relative risk for developing HIV peripheral neuropathy (OR: 2.9 and 7.7 respectively), while conversely, carriers of IL2+166/rs2069763 TT genotype yielded lower probability (OR: 3.1), all however, with marginal statistical significance. The latter, if confirmed in a larger Greek population cohort, may offer in the future novel genetic markers to identify susceptibility, while it remains significant that further ethnicity-oriented studies continue to be conducted in a similar pursuit.

The role of oxidative stress in the pathogenesis of Graves’ orbitopathy

Graves’ disease (GD) is a chronic autoimmune condition in which the anti-thyroid stimulating hormone receptor antibodies (TRAb) activate the thyrotropin receptor (TSHR) located on thyrocytes, leading to excessive thyroid hormone production. TSHR is also expressed in extrathyroidal tissues, in particular, within the orbit. The serum levels of TRAb correlate with the severity and activity of thyroid orbitopathy (TO). TO is the most common extrathyroidal manifestation of GD. It is an autoimmune inflammation of orbital tissues, that is, extraocular muscles, orbital adipose tissue or a lacrimal gland. Increased orbital fibroblast and adipocyte proliferation, overproduction of glycosaminoglycans, as well as extraocular muscle oedema, result in increased orbital tissue volume and trigger the onset of TO symptoms. The pathophysiology of TO is complex and has not been fully unexplained to date. Orbital fibroblasts show expression of the TSHR, which is the main target of autoimmunity. It has been hypothesised that T-cell activation induced by orbital receptor stimulation by the target antibody results in orbital tissue infiltration, triggering a cascade of events which leads to the production of cytokines, growth factors and reactive oxygen species (ROS). ROS cause damage to many components of the cell: the cell membrane through the peroxidation of lipids and proteins leading to a loss of their function and enzymatic activity. Oxidative stress leads to the activation of the antioxidant system, which operates through two mechanisms: enzymatic and non-enzymatic. Assessment of the concentration of oxidative stress markers and the concentration or activity of anti-oxidative system parameters enables the evaluation of oxidative stress severity, which in the future may be utilized to assess treatment efficacy and prognosis in patients with active OT.

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.

Differential profiling of lacrimal cytokines in patients suffering from thyroid-associated orbitopathy

The aim was to investigate the levels of cytokines and soluble IL-6R in the tears of patients with thyroid-associated orbitopathy (TAO) disease. Schirmer’s test was adopted to collect tears from TAO patients (N = 20, 17 women, mean age (±SD): 46.0 years (±13.4)) and healthy subjects (N = 18, 10 women, 45.4 years (±18.7)). Lacrimal cytokines and soluble IL-6R (sIL-6R) were measured using a 10-plex panel (Meso Scale Discovery Company) and Invitrogen Human sIL-6R Elisa kit, respectively. Tear levels of IL-10, IL-12p70, IL-13, IL-6 and TNF-α appeared significantly higher in TAO patients than in healthy subjects. Interestingly, IL-10, IL-12p70 and IL-8 levels increased in tears whatever the form of TAO whereas IL-13, IL-6 and TNF-α levels were significantly elevated in inflammatory TAO patients, meaning with a clinical score activity (CAS) ≥ 3, compared to controls. Furthermore, only 3 cytokines were strongly positively correlated with CAS (IL-13 Spearman coeff. r: 0.703, p = 0.0005; IL-6 r: 0.553, p = 0.011; IL-8 r: 0.618, p = 0.004, respectively). Finally, tobacco use disturbed the levels of several cytokines, especially in patient suffering of TAO. The differential profile of lacrimal cytokines could be useful for the diagnosis of TAO patients. Nevertheless, the tobacco use of these patients should be taken into account in the interpretation of the cytokine levels.

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.

Comprehensive analysis of cytokine gene polymorphisms defines the association of IL-12 gene with ophthalmopthy in Korean children with autoimmune thyroid disease

In early onset autoimmune thyroid disease (AITD) showing a strong genetic tendency, cytokines have been suggested to play a critical role in the development of AITD. To directly compare the influences of several cytokine gene polymorphisms, 25 single nucleotide polymorphisms (SNPs) in 17 cytokine genes were analyzed on 104 Korean children with AITD [Hashimoto's disease (HD) = 44, Graves' disease (GD) = 60 (thyroid-associated ophthalmopathy (TAO) = 29, non-TAO = 31)] and 192 controls. Compared with healthy controls, any significant association with polymorphisms of cytokine genes was not found in HD and GD. Among GD patients, non-TAO group only showed significant associations with IL-12 C allele (rs3212227: A > C) (76.6% vs. 51.6%, OR = 0.3 [0.15-0.71], Pc = 0.007). Particularly, the frequency of IL-12C allele was significantly lower in the non-TAO group than in the TAO group (82.8% vs. 51.6%, Pc = 0.018). Our comprehensive analysis of cytokine gene polymorphisms suggests that IL-12 gene may play impact on specific pathogenesis of ophthalmopathy in Korean children with AITD.

Serum concentrations of HGF and IL-8 in patients with active Graves' orbitopathy before and after methylprednisolone therapy

INTRODUCTION

Graves' disease is the most common cause of hyperthyroidism, and orbitopathy is the most frequent extrathyroidal manifestation of Graves' disease. The aims of this study were as follows: (1) to evaluate the serum concentration of HGF and IL-8 in the blood of newly diagnosed Graves' disease patients with the first episode of active GO and healthy controls; (2) to estimate the influence of the thyroid function (euthyreosis vs. hyperthyreosis) on HGF and IL-8 blood levels in patients with active GO; (3) to evaluate the influence of intravenous (i.v.) methylprednisolone (MP) pulse therapy and additional oral MP treatment on HGF and IL-8 blood levels in patients with active GO.

PATIENTS AND METHODS

Thirty-nine Graves' disease patients with the first episode of clinically active GO (Group A) were enrolled in the study. To estimate the influence of the thyroid function on serum concentrations of the studied proangiogenic factors, Group A was divided into Group A I (n = 18) in euthyroid and Group A II (n = 21) in hyperthyroid stage of Graves' disease in moderate-to-severe stage of GO. The control group consisted of 20 healthy volunteers age- and sex-matched to the GO group. Concentrations of the studied proangiogenic factors in serum samples were measured by an enzyme-linked immunosorbent assay before (Group A) and after (Group A1) intensive pulse i.v.MP treatment and 1 month after the end of additional oral MP treatment (Group A2).

RESULTS

We found a significant increase in serum concentrations of studied factors in the GO group before immunosuppressive therapy when compared with the control group and decrease after i.v.MP treatment. One month after the end of additional oral MP treatment (Group A2), serum concentrations of HGF and IL-8 still decreased and no significant difference was observed in HGF and IL-8 concentrations when compared with the control group. We did not find the difference in serum concentration of the studied proangiogenic factors between patients in euthyroid and hyperthyroid stage of Graves' disease before MP therapy.

CONCLUSIONS

Serum HGF and IL-8 concentrations are elevated in Graves' disease patients with active Graves' orbitopathy as compared to the healthy control group. Successful management of active Graves' orbitopathy with glucocorticoids is associated with a decrease in HGF and IL-8 serum concentrations.

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.

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.

Association between age at diagnosis of Graves' disease and variants in genes involved in immune response

Background

Graves' disease (GD) is a complex disease in which genetic predisposition is modified by environmental factors. The aim of the study was to examine the association between genetic variants in genes encoding proteins involved in immune response and the age at diagnosis of GD.

Methods

735 GD patients and 1216 healthy controls from Poland were included into the study. Eight genetic variants in the HLA-DRB1, TNF, CTLA4, CD40, NFKb, PTPN22, IL4 and IL10 genes were genotyped. Patients were stratified by the age at diagnosis of GD and the association with genotype was analysed.

Results

Polymorphism in the HLA-DRB1, TNF and CTLA4 genes were associated with GD. The carriers of the HLA DRB1*03 allele were more frequent in patients with age at GD diagnosis ≤30 years than in patients with older age at GD diagnosis.

Conclusions

HLADRB1*03 allele is associated with young age at diagnosis of Graves' disease in polish population.

Thymic stromal lymphopoietin gene promoter polymorphisms and expression levels in Graves' disease and Graves' ophthalmopathy

Background

Graves disease (GD) is an organ-specific autoimmune disease characterized by hyperthyroidism, diffuse goiter, autoantibodies against thyroid-specific antigens, and dermopathy. Studies of GD have demonstrated the importance of the Th2 and Th17 immune responses in mediating disease progression. In the present study, we investigated the role of a Th2 cytokine, thymic stromal lymphopoietin (TSLP), in GD and Th17 differentiation.

Methods

In this study, we genotyped 470 patients with GD at 3 single nucleotide polymorphisms (SNPs) in TSLP. In addition, the serum concentrations of TSLP were determined in 432 patients and 272 controls. Ten patients and controls each were further screened using in vitro Th17 differentiation assays. The SNPs were genotyped using ABI TaqMan® SNP genotyping assays. For the Th17 differentiation assays, peripheral blood mononuclear cells (PBMCs) isolated from the patients and controls were placed into Th17 differentiation media, and interleukin 17 expression levels were determined.

Results

Haplotype analysis indicated that patients with the Ht3 (TCC) haplotype have a 3.28-fold higher risk of developing GD (p = 0.007), whereas those with the Ht5 (TCG) haplotype had a 0.03-fold, reduced risk of developing GD (p = 1 × 10⁻¹⁴). SNP rs3806933 (p = 0.007) was associated with female Graves ophthalmopathy (GO). TSLP expression levels were higher in GD patients than in control subjects, and TLSP was also shown to promote the differentiation of Th17 cells in GD patients.

Conclusions

These results suggest that polymorphisms in TSLP may be used as genetic markers for the diagnosis and prognosis of GD. Furthermore, TLSP may be a target for treating GD.

Cytometric evaluation of intracellular IFN-γ and IL-4 levels in thyroid follicular cells from patients with autoimmune thyroid diseases

BACKGROUND

In recent few years is underlined that altered balance of pro- and anti-inflammatory cytokines play an important role in the pathogenesis of AITD.The aim of this study was to estimate intracellular INF-γ and IL-4 levels in thyroid-infiltrating lymphocytes and thyrocytes isolated from thyroid tissues in 54 adolescent patients aged 8-21 years, with Graves' disease (GD; n = 18), Hashimoto's thyroiditis (HT; n = 18) and non-toxic multinodular goiter (NTMG; n = 18).

METHODS

Fresh thyroid tissues were taken on culture medium RPMI -1640, it was mechanically prepared. In next step were added cell activators -12- myristate 13- the acetate (PMA) and Ionomycin as well as the inhibitor of transportation of proteins - Breferdin A. They were cultured 24 hours in 50 ml flasks at 37°C in a 5-95% CO2-air water-saturated atmosphere. After that, thyrocytes were identified by mouse mAb directed against human TPO epitope 64 conjugated with rabbit anti-mouse antibodies IgG (Fab')2 labeled by FITC. After incubation at room temperature to each of samples added reagent A fixative the cellular membrane. In next step into the cell suspensions were added reagent B to permeabilization of cellular membrane and specific anti-IL-4-PE or anti-IFN-γ-PE mAbs. Identification of intracellular cytokines in T lymphocytes was performed in the same procedure with application of anti-CD4-PerCP and anti-CD8-PerCP mAbs specific for T lymphocytes. The cells were analyzed in a flow cytometry (Coulter EPICS XL).

RESULTS

In examined group of patients with GD we observed statistically significant higher mean percentage of cells with phenotype CD4+IL-4 (p < 0.05; p < 0.025), CD8+IL-4 (p < 0.033; p < 0.01) and TFCs-IL-4+ (p < 0.05; p < 0.01) in comparison to patients with HT and NTMG. The analysis of mean percentages of positive TILs and TFCs with intracellular INF-g levels in patients with HT revealed statistically significant increase percentage of CD4+INF-γ (p < 0.04; p < 0.001), CD8+ INF-γ (NS; p < 0.025), TFCs+INF-γ (p < 0.03; p < 0.001) cells in comparison to the percentage of positive cells from patients with GD and NTMG.

CONCLUSIONS

We conclude that human thyrocytes in autoimmune thyroid disorders could be a source of cytokine production and that their activation influences local interaction with T lymphocytes inflowing to the thyroid gland.

Transforming growth factor β signaling pathway associated gene polymorphisms may explain lower breast cancer risk in western Indian women

Transforming growth factor β1 (TGFB1) T29C and TGF β receptor type 1 (TGFBR1) 6A/9A polymorphisms have been implicated in the modulation of risk for breast cancer in Caucasian women. We analyzed these polymorphisms and combinations of their genotypes, in pre menopausal breast cancer patients (N = 182) and healthy women (N = 236) from western India as well as in breast cancer patients and healthy women from the Parsi community (N = 48 & 171, respectively). Western Indian women were characterized by a higher frequency of TGFB1*C allele of the TGF β T29C polymorphism (0.48 vs 0.44) and a significantly lower frequency of TGFBR1*6A allele of the TGFBR1 6A/9A polymorphism (0.02 vs 0.068, p<0.01) as compared to healthy Parsi women. A strong protective effect of TGFB1*29C allele was seen in younger western Indian women (<40 yrs; OR = 0.45, 95% CI 0.25-0.81). Compared to healthy women, the strikingly higher frequencies of low or intermediate TGF β signalers in patients suggested a strong influence of the combination of these genotypes on the risk for breast cancer in Parsi women (for intermediate signalers, OR = 4.47 95%CI 1.01-19.69). The frequency of low signalers in Parsi healthy women, while comparable to that reported in Europeans and Americans, was three times higher than that in healthy women from western India (10.6% vs 3.3%, p<0.01). These observations, in conjunction with the low incidence rate of breast cancer in Indian women compared to White women, raise a possibility that the higher frequency of TGFB1*29C allele and lower frequency of TGFBR1*6A allele may represent important genetic determinants that together contribute to a lower risk of breast cancer in western Indian women.

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.