TNF-alpha and TNF-beta gene polymorphisms in systemic sclerosis

Tumor necrosis factor (TNF)-alpha and TNF-beta, mediators of inflammatory responses, have been implicated in the pathogenesis of autoimmune diseases. The aim of this investigation was to determine whether two promoter region polymorphisms of the TNF-alpha gene (TNF-alpha -308 and TNF-alpha -238) and a determinant in the first intron of the TNF-beta gene (TNF-beta +252) affect susceptibility to systemic sclerosis (scleroderma) (SSc). Fifty patients and 60 healthy blood donors from Japan were genotyped for these markers by polymerase chain reaction-based methods. Fisher's exact test was used to test for significant associations. Because of very limited variation at the TNF-alpha -308 and TNF-alpha -238 loci in the Japanese people, statistical analyses with sufficient power could not be done for these genotypes. However, the two homozygous genotypes of the TNF-beta +252 locus were found to be significantly associated with SSc. Compared to controls, the frequency of the TNF-1 genotype was decreased, whereas that of TNF-2 was increased in SSc patients. The former implies an association with resistance, while the latter suggests an association with susceptibility to the disease. These results show that the TNF-beta +252 locus plays an important role in the etiopathogenesis of SSc.     

Proximal interleukin-10 gene polymorphisms in Italian patients with systemic sclerosis

Interleukin-10 (IL-10) can favour the development of fibrosis by promoting a relative shift towards T helper 2 responses. Three single base pair substitutions in the 5' flanking region of the IL-10 gene (G/A -1082, C/T -819 and C/A -592) influence the amount of IL-10 secreted in cell cultures: the GCC haplotype is associated with an increased production, while the ACC and the ATA haplotypes are associated with intermediate and decreased production. Accordingly, three phenotypes have been individuated: high producers (GCC+/GCC+), medium producers (GCC+/GCC-) and low producers (GCC-/GCC-). We hypothesised that IL-10 haplotypes and genotypes are differently expressed in patients with systemic sclerosis (SSc) with the limited cutaneous SSc (lcSSc) subset or the diffuse cutaneous SSc (dcSSc) subset. One hundred and sixty-one unrelated Italian patients with SSc and 94 controls have been included. Their DNA was extracted and stored before being analysed by polymerase chain reaction with sequence-specific primers. The GCC haplotype is overrepresented in patients with SSc; subjects with dcSSc were the primary contributors to these results (dcSSc: 52.2% vs controls: 37.2%; chi2= 8.519, 2 d.f., corrected P= 0.04). In Scl70-positive patients, the GCC haplotype increased the likelihood of presenting the dcSSc subset [chi2= 12.56, P < 0.0005; odds ratio (OR) = 3.89, 95% confidence interval (CI(95)) = 1.69-9.08]; these results were confirmed at the phenotypic level (chi2= 11.67, 2 d.f., P= 0.003). In Scl70-positive patients, the high-producing phenotype was associated with poor survival, independently from disease subset and gender (hazard ratio = 9.9, CI(95)= 1.6-61.27, P < 0.05). The IL-10 haplotype and genotype associated with high IL-10 production may alter the susceptibility to SSc and/or its expression, increasing the prognostic value of other well-known markers of disease severity.     

Novel mutation in AIRE gene with autoimmune polyendocrine syndrome type 1

PurposeAutoimmune polyendocrine type 1 (APS-1) is a complex inherited autosomal recessive disorder. Classically, it appears within the first decade of life followed by adrenocortical insufficiency, mucocutaneous candidiasis, Addison's disease, and hypoparathyroidism. The clinical phenotype of APS-1 varies depending upon mutations in the autoimmune regulator gene (AIRE) on chromosome 21q22.3.MethodsIn this study, we performed Sanger sequencing ofAIRE in Iranian patients to identify different variants and probable new mutations corresponding to a clinical diagnosis of APS-1.ResultsAfter analyzing 14AIRE exons, we detected a novel insertion mutation in exon 2 in a patient who presented with severe APS-1, Lys50AsnfsX168. Furthermore, the known mutations in AIRE, including Arg139X, Arg257X, and Leu323SerfsX51, were detected in enrolled patients.DiscussionAccording to our results, sequencing analysis ofAIRE provides a useful screening method to diagnose patients with incomplete or unusual clinical presentations of APS-1.     

Lithium associated autoimmune thyroiditis.

A case of autoimmune thyroiditis after long term treatment with lithium is described in a 29 year old Japanese woman with manic depression. Positive serum antithyroglobulin and antimicrosomal antibodies, diffuse goitre, and microscopic chronic thyroiditis, as well as the clinical history of long term lithium treatment were suggestive of lithium associated autoimmune thyroiditis. Microscopically, there was a mild degree of interstitial fibrosis and a moderate degree of lymphocytic infiltration. Some areas showed a moderate degree of stromal fibrosis and atrophic thyroid follicles. Lymphoid follicles with germinal centres, disrupted thyroid follicles with lymphocytic infiltration, and Hürthle cells were also observed. The differential diagnosis in patients presenting with these histological features includes painless (silent) thyroiditis, autoimmune thyroiditis and lithium associated autoimmune thyroiditis. A detailed clinical history is essential if the correct diagnosis is to be reached.     

Association of CTLA-4 gene promoter polymorphisms with systemic sclerosis in Iranian population

In a recent study, we were unable to show any association between CTLA-4 exon-1 polymorphism and systemic sclerosis (SSc) in Iranian population. In order to further explore the role of this immune inhibitory gene in SSc development, in the present study, the polymorphisms in the CTLA-4 promoter region (-1,722 T/C, -1,661 A/G and -318 C/T) were investigated in 83 SSc patients and 166 healthy controls. All genotypes and allele frequencies in patients were significantly different from the control group (P=0.022 for -1,722 T/C, P=0.03 for -1,661 A/G and P=0.014 for -318 C/T genotypes). The -1,722C, -1,661G and -318T alleles contributed to SSc with P=0.012, odds ratio (OR) 2.16, P=0.031, OR 1.82 and P=0.023, OR 2.45, respectively. A significant difference was observed in the frequency homozygous 'genotype combination' -1,722TT/-1,661AA/-318CC of these three polymorphisms (P(c)=0.003). The frequency of this genotype combination was significantly higher in the control group than in patients. Results of this investigation indicate that -1,722C, -1,661G and -318T alleles of CTLA-4 gene promoter appear to be associated with SSc, and individuals carrying these alleles may be more susceptible to this disease.     

Interleukin-10 genotypes are associated with systemic sclerosis and influence disease-associated autoimmune responses

Systemic sclerosis (SSc; scleroderma) is a connective tissue disease, characterized by fibrotic, immunological, and vascular abnormalities. Interleukin-10 (IL-10) is an anti-inflammatory cytokine that modulates collagen production and B-cell survival. To determine if certain IL-10 genotypes are risk factors for the development of SSc and influence disease-associated autoimmune responses, 248 Caucasian and 264 Japanese SSc patients and controls were genotyped for three loci: -3575, -2849, and -2763. Sera from patients were characterized for SSc-associated autoantibodies. In Caucasians, at -3575 and -2763, the frequency of AA homozygotes was higher in patients as compared with controls (P=0.0005; P=0.002). In Japanese subjects, the frequency of AC heterozygotes at -2763 was higher, and that of CC homozygotes lower, in patients with diffuse SSc as compared to controls (P=0.04). Particular IL-10 genotypes were associated with SSc-related autoantibodies. These results suggest that IL-10 genotypes contribute to the etiology of scleroderma.     

Fas ligand gene polymorphisms are not associated with Hashimoto's thyroiditis and Graves' disease

Hashimoto's thyroiditis and Graves' disease represent the two most common autoimmune thyroid disorders. Whereas in Hashimoto's thyroiditis FasL expression causes thyrocytes to undergo apoptosis, additional anti-apoptotic molecules appear to protect these cells in Graves' disease. Mutations of the FasL gene were observed in systemic lupus erythematosus. Given its functional relevance for the pathogenesis of thyroid autoimmunity we wondered whether variants of the FasL gene play a role in Hashimoto's thyroiditis and Graves' disease. We genotyped families with at least one offspring affected by Hashimoto's thyroiditis (n = 86) and Graves' disease (n = 90) for two FasL gene polymorphisms (C -843 T in the promoter, A IVS2nt-124 G in intron 2). Extended transmission disequilibrium (ETDT) and chi(2) testing were performed. Neither polymorphism alone nor the promoter/intron 2 haplotypes (p = 0.91) were associated with Hashimoto's thyroiditis. No association with Graves' disease was observed for the promoter polymorphism (p = 0.91) and the intron 2 "A" allele (57.1%; p = 0.36) or the promoter/intron 2 haplotypes (p = 0.31). Moreover, intron 2 genotyping revealed no difference between an additional 251 patients with Graves' disease and 197 healthy controls (p = 0.37). Italian and German families did not differ for the studied polymorphisms. In conclusion, our data do not suggest common genetic FasL variants to significantly contribute to the pathogenesis of either Hashimoto's thyroiditis or Graves' disease.     

Malignancies associated with systemic sclerosis

The outcome of systemic sclerosis (SSc) has become more favorable during the past years. Respiratory failure or renal crisis became less frequent, therefore more attention should be paid to long-term comorbidities, such as malignancies secondary to scleroderma. The incidence of malignant lymphoproliferative diseases, as well as that of solid tumors are higher in a number of rheumatic diseases including SSc. Some cytotoxic agents, primarily cyclophosphamide used in the treatment of SSc, as well as exposure to chemicals or smoking may further increase cancer risk. We also present malignancies in 218 scleroderma patients undergoing follow-up in our department were assessed for secondary malignancies. Although the number of SSc patients with tumor is relatively small, we compared our cohort to the Health for All Hungarian database and calculated standard incidence ratios (SIR). We identified 11 cases of malignancy in 10 SSc patients (4.6%). One patient had two types of tumor: breast cancer before the onset of SSc and later malignant lymphoma. Half of SSc patients with cancer belonged to the diffuse cutaneous (dcSSc) subtype. The mean age at onset of SSc was 54.6years, while that at the diagnosis of malignancy was 61.5years. The mean disease duration of scleroderma at the time of cancer diagnosis was 6.6years. Five patients died, 4 due to the underlying malignancy. Among the five surviving patients, the mean survival time was 4.9years. Altogether 3 patients had non-Hodgkin's lymphoma, 2 had bronchial cancer, 2 had breast cancer, one had leiomyosarcoma of the leg, one had esophageal cancer, one had cervix cancer and one had skin cancer. In comparison to the Health for All database, the overall SIR of all malignancies in SSc was 1.07 (CI: 0.82-1.38) varying between 5.8 and 52.4 in different tumor types. Only one cancer patient received cyclophosphamide therapy. In conclusion, secondary tumors including lung, skin and breast cancer, as well as lymphomas are more common in SSc than in the general population. The adequate treatment and follow-up of scleroderma patients may help us to lower the risk of malignancies secondary to SSc.     

Interleukin-1 gene complex polymorphisms in systemic sclerosis patients with severe restrictive lung physiology

Increased concentrations of interleukin-1 (IL-1) were observed in bronchoalveolar lavage fluids from patients with systemic sclerosis (SSc), and their levels were correlated with the patients' forced vital capacity (FVC). Because IL-1 production is regulated at the genetic level, we hypothesized that IL-1 gene complex single nucleotide polymorphisms (SNPs) might be relevant to the progression of ventilatory restriction in SSc. Two-hundred four Italian SSc patients were genotyped for the following IL-1 gene complex SNPs: IL-1alpha C-889T, IL-1beta C+3962T, IL-1beta C-511T, IL-1R Cpst1970T, and IL-1Ra Cmspal11100T, as well as for the following SNPs of cytokines with regulatory functions on IL-1 production: IFNgamma AUTR5644T, TNFalpha A-308G, and IL-10 A-1082G. The SNPs were inserted in a Cox regression model with disease subset, gender, autoantibodies, age at onset of disease, and prior use of immunosoppresants as covariates and the presence of FVC<55% of predicted values as outcome measure; p values were corrected for the number of pairwise comparisons. Twenty-five patients (12.3%) developed a severe ventilatory restriction after 6.8+/-6.6 years (mean+/-standard deviation) from diagnosis. In our model, the relative risk to develop a severe ventilatory restriction was increased by the antitopoisomerase I antibody (p=0.01; HR=14.67, CI95=1.87-114.92), the dcSSc subset (p=0.007; HR=3.14, CI95=1.36-7.21) and the IL-1beta C+3962T SNP (p=0.003 TT vs CC; HR=6.61, CI95=2.28-19.15). The IL-1beta C+3962T SNP is associated with the presence of severe restrictive lung physiology in Italian SSc patients.     

MYO9B gene polymorphisms are associated with autoimmune diseases in Spanish population

The aim of the study was to test MYO9B gene polymorphisms for association with three autoimmune diseases, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and celiac disease (CD), in a Spanish population. We analyzed three SNPs (rs2305767, rs1457092, and rs2305764) in a case-control cohort composed of 349 SLE patients, 356 RA patients, 90 CD patients, and 345 healthy controls. All three SNPs showed a consistent increased frequency of the A allele in SLE, RA, and CD patients compared with healthy controls. An association was observed between CD and rs2305764 (p=0.01, OR=2.3), between SLE and rs1457092 (p=0.002, OR=1.4), and between RA and rs1457092 (p=0.02, OR=1.3). The three autoimmune diseases combined showed significant association with rs1457092 and rs2305764 and with the AAA haplotype (p haplotype=0.005, OR=1.3). Our data demonstrate consistent association with the A allele and AAA haplotype of three SNPs in the MYO9B gene, which were previously reported to be associated with CD in the Dutch population. This suggests that genetic variation in MYO9B is associated with CD, SLE, and RA and that MYO9B is a general risk factor for autoimmunity.     

Association of osteopontin regulatory polymorphisms with systemic sclerosis

To test the involvement of osteopontin gene (OPN) in systemic sclerosis (SSc) susceptibility, two OPN single nucleotide polymorphisms previously reported to be associated with systemic lupus erythematosus, namely −156G/GG (proximal promoter) and +1239A/C (3′ untranslated region (UTR)), were tested in 357 Italian patients and 864 matched control subjects. OPN serum levels were determined by enzyme-linked immunosorbent assay in 32 patients and 116 controls. Compared with the controls, in SSc patients there was a significantly increased frequency of the alleles −156G (p = 0.0086), and +1239C (p = 0.00064), paralleling the association reported for systemic lupus erythematosus. According to logistic regression analysis, this association is primarily due to the effect of +1239 single nucleotide polymorphism. OPN serum levels were significantly higher in SSc patients than in controls (p = 0.00025). These data suggest that OPN genetic variations have a role in SSc susceptibility, reporting for the first time an involvement of this molecule in SSc pathogenesis and emphasizing that SSc shares pathogenetic mechanisms with other autoimmune diseases.     

Association of TAP1 and TAP2 gene polymorphisms with systemic sclerosis in Korean patients

We sought to determine whether transporter associated with antigen processing (TAP) gene polymorphism is associated with susceptibility to systemic sclerosis (SSc). TAP1 and TAP2 gene polymorphisms were analyzed in 61 Korean patients with SSc and 100 ethnically matched healthy Koreans by polymerase chain reaction-restriction fragment length polymorphism. Human leukocyte antigen (HLA)-DRB1 genotyping data of the patients from our previous study was used for the assessment of independent role of TAP genes to SSc susceptibility. Patients were stratified according to anti-topoisomerase I (anti-topo I) antibody status and clinical subsets of diffuse and limited cutaneous SSc (dcSSc and lcSSc). TAP1 and TAP2 gene polymorphisms were associated with different subsets of SSc: TAP1*A/A genotype with anti-topo I-positive dcSSc (p = 0.01, p corrected = 0.04), TAP2*A1/C genotype with anti-topo I-positive lcSSc (p < 0.05), TAP2*Bky2 and *C alleles with anti-topo I-negative dcSSc (both p < 0.05), and TAP2*B/E genotype with anti-topo I-negative lcSSc (p = 0.004). Although TAP gene associations were generally weak, some associations (TAP2*A1/C, TAP2*C, and TAP2*B/E) with different subsets of SSc were independent of HLA-DR associations, revealing even stronger associations (TAP2*A1/C and TAP2*C) among individuals not possessing the risk HLA-DR alleles. These results suggest the possible role of TAP gene polymorphisms in the genetic susceptibility to SSc.     

Indoleamine 2,3 dioxygenase gene polymorphisms correlate with CD8+ Treg impairment in systemic sclerosis

Systemic sclerosis (SSc) is characterized by tissue fibrosis, vasculopathy and autoimmunity. Indoleamine 2,3 dioxygenase (IDO) plays a pivotal role in immunological tolerance modulating regulatory T cell (Treg) generation and function. Single nucleotide polymorphisms (SNPs) of IDO gene could impact on Treg function and predispose to autoimmunity. Here, the existence of an association between specific IDO SNPs and SSc was analyzed.     

Prolactin and prolactin receptor gene polymorphisms in multiple sclerosis and systemic lupus erythematosus

Genes encoding for prolactin (PRL) and its receptor (PRLR) are possible candidates for multiple sclerosis (MS) and systemic lupus erythematosus (SLE) susceptibility. In fact: (1) a prolactin secretion dysfunction has been described in several autoimmune diseases including SLE and MS and their animal models; (2) both PRL and PRLR are structurally related to members of the cytokine/hematopoietin family and have a role in the regulation of the immune response; and (3) both PRL and PRLR genes map in genomic regions that showed linkage with autoimmunity. Prolactin maps on chromosome 6p, about 11-kb telomeric to HLA-DRB1 and PRLR in 5p12-13, which revealed evidence of linkage with MS in different populations. To evaluate a possible role of these two genes in SLE and MS we performed an association study of 19 PRL and PRLR single nucleotide polymorphisms (SNPs). These were directly searched by DHPLC in a panel of SLE and MS patients and selected from databases and the literature. The SNP allele frequencies were determined on patient and control DNA pools by primer-extension genotyping and HPLC analysis. Moreover a panel of HLA typed SLE and control individuals were individually genotyped for the PRL G-1149T polymorphism previously described to be associated with SLE. No statistically significant difference in the allele distribution was observed for any of the tested variations.     

Transforming growth factor-beta1 polymorphisms in Korean patients with systemic sclerosis

Transforming growth factor-beta1 (TGF-beta1) plays an important role in the pathogenesis of systemic sclerosis (SSc). To investigate the role of TGF-beta1 gene polymorphisms in SSc, we genotyped six biallelic polymorphic positions (position -988, -800, and -509; and codons 10, 25, and 263) in 61 Korean SSc patients and in 148 healthy controls, using polymerase chain reaction-sequence-specific primers. Genetic polymorphisms were found at position -509 and codon 10 in Koreans. The allele frequencies of C/T at position -509 were 0.59/0.41 in patients and 0.56/0.44 in controls. The allele frequencies of C/T at codon 10 were 0.40/0.60 in patients and 0.50/0.50 in controls. In conclusion, no skewed distribution of TGF-beta1 gene polymorphisms was found in Korean patients with SSc.