RESUMO
Rheumatoid Arthritis (RA) is a multifactorial autoimmune disease. Currently, several genes play an important role in the development of the disease. The objective was to evaluate the association of the STAT4 rs7574865 and rs897200 gene variants with RA susceptibility, DAS28, RF, and anti-CCP in Western and Southern Mexico populations. Genotyping was performed on 476 samples (cases = 240; controls = 236) using the Taqman® system and qPCR probes. Disease activity was assessed using DAS28 and HAQ DI. CRP, ESR, RF, and anti-CCP were determined for clinical assessment. Our study showed there is a statistically significant association with susceptibility to RA for the rs7574865 variant in the Western population for the GT and TT genotypes. The same genotypes also showed a moderate-to-high activity according to DAS28 and positive anti-CCP compared to the control group. This association was not found in the Southern population. This work confirms the association of the rs7574865 variant with RA, as well as a moderate-to-high activity and positive anti-CCP in the Western population but not in the Southern population. No association of the rs897200 variant was found in any of the studied populations.
Assuntos
Anticorpos Antiproteína Citrulinada , Artrite Reumatoide , Humanos , México , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Artrite Reumatoide/genética , Fator de Transcrição STAT4/genéticaRESUMO
STAT4 plays an important role in disease activity in SLE patients. STAT4 particles have the capacity to activate the transcription of genes associated with the production of TH1 and Th17 lymphocytes, with a greater predominance on the production of IFN-γ and IL-17A. The presence of variants in STAT4 genes has a major impact on the generation of autoimmunity. However, there are few studies evaluating the impact of these variants on the production of proinflammatory cytokines such as IFN-γ and IL-17A. Methods-A case-control study was carried out with 206 Mexican mestizo patients residing in Western Mexico with a diagnosis of SLE and a group of 80 patients without autoimmune diseases was captured to determine the cut-off point for high IFN-γ levels. In this study, SLE patients with high IFN-γ levels were considered as cases (cut-off > 15.6 pg/mL), and SLE patients with normal IFN-γ levels were considered as controls (cut-off ≤ 15.6 pg/mL). Disease activity was identified from the systemic lupus erythematosus disease activity index (SLEDAI). For the determination of levels of cytokines IFN-γ, IL-12, and IL17A, commercial ELISA kits were used. Genotyping of STAT4 rs7574865 (G > T) was performed by quantitative polymerase chain reaction (qPCR) using TaqMan probes. Results-The patients with SLE had a median age of 45 years with a range of disease duration from 4 years to 18 years; 45.6% were identified as having disease activity. In this sample, we identified a high IFN-γ prevalence of 35.4%. The levels of IFN-γ were higher in the patients with genotype TT than GG. We found that TT genotype conferred a higher risk of high IFN-γ when compared to the GG and GT genotypes. Conclusions-In this study, we identified that the polymorphic genotype TT of the STAT4 gene rs7574865 polymorphism is associated with increased levels of IFN-γ. However, its strength of association was weak, so complementary studies are needed to evaluate its impact on SLE patients.
Assuntos
Doenças Autoimunes , Interferon gama , Lúpus Eritematoso Sistêmico , Fator de Transcrição STAT4 , Pré-Escolar , Humanos , Alelos , Doenças Autoimunes/genética , Doenças Autoimunes/metabolismo , Estudos de Casos e Controles , Citocinas/genética , Predisposição Genética para Doença , Interferon gama/genética , Interleucina-17/genética , Lúpus Eritematoso Sistêmico/genética , Lúpus Eritematoso Sistêmico/metabolismo , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genéticaRESUMO
OBJECTIVE: Variants in STAT4 are associated with systemic lupus erythematosus (SLE) and other autoimmune diseases. We undertook this study to investigate how disease-associated variants affect STAT4 expression, in particular in CD4+ T cells where STAT4 plays an essential role. METHODS: We compared Th1 differentiation between naive CD4+ T cells from healthy donors homozygous for the risk (R/R) or nonrisk (NR/NR) alleles. We analyzed epigenetic marks in STAT4 and evaluated the relevance of its third intron, assessed the consequences of Stat4 overexpression in vivo in mice, and analyzed the effects of the STAT4 genotype in patients with lupus nephritis. RESULTS: Naive CD4+ T cells from NR/NR healthy donors down-regulated STAT4 in response to interleukin-12 (IL-12). In contrast, cells from R/R healthy donors maintained high levels. R/R cells exhibited a higher abundance of transcriptionally active STAT4 and increased interferon-γ production. Accordingly, R/R healthy donors exhibited a stronger induction of local active enhancer marks. Genetic editing confirmed the presence of a negative regulatory region in the STAT4 third intron, where most of the SLE-associated STAT4 single-nucleotide polymorphisms (SNPs) are located. In vivo forced expression demonstrated that increases in Stat4 levels in T cells enhanced glomerulonephritis in mice. Accordingly, the R/R genotype was associated with suboptimal response to treatment and with worse clinical outcomes in patients with proliferative lupus nephritis. CONCLUSION: The SLE-associated STAT4 haplotype correlates with an abnormal IL-12-mediated STAT4 transcriptional regulation. Carriers of the risk variant exhibit exaggerated CD4+ proinflammatory capacities that, in the context of SLE, contribute to more severe disease. R/R patients may benefit from blockade of the IL-12/STAT4 pathway.
Assuntos
Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Animais , Camundongos , Linfócitos T CD4-Positivos/metabolismo , Regulação para Baixo , Haplótipos , Interferon gama/genética , Interleucina-12 , Lúpus Eritematoso Sistêmico/genética , Nefrite Lúpica/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , HumanosRESUMO
BACKGROUND: Takayasu arteritis (TAK) is considered a rare disease characterized by nonspecific inflammation of the large arteries, especially the aorta and its major branches. Because TAK is an autoimmune disease (AD), it could share susceptibility loci with other pathologies such as systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA), among others. Widely explored polymorphisms in non-HLA genes, including TNFAIP3, STAT4, TNFSF4, BANK1, and BLK have been consistently associated with both SLE and RA, but they have not been evaluated in TAK. OBJECTIVE: The aim of our study was to investigate whether TNFAIP3, STAT4, BANK1, BLK, and TNFSF4 polymorphisms are associated with susceptibility to TAK. METHODS: The TNFAIP3 rs2230926T/G and rs5029924C/T, STAT4 rs7574865G/T, BANK1 10516487G/A, BLK rs2736340T/C, rs13277113A/G, and TNFS4 rs2205960G/T polymorphisms were genotyped in 101 cases and 276 controls by using a TaqMan SNP genotyping assay. An association analysis was performed. RESULTS: The TNFAIP3 rs2230926T/G and rs5029924C/T polymorphisms were in complete linkage disequilibrium and turned out to be risk factors for TAK (OR = 4.88, p = 0.0001). The STAT4, BANK1, BLK, and TNFSF4 polymorphisms were not associated with the disease. CONCLUSIONS: This is the first study documenting an association of TNFAIP3 rs2230926T/G and rs5029924C/T with TAK. Our results provide new information on the genetic bases of TAK.
Assuntos
Genótipo , Arterite de Takayasu/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Ligante OX40/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Quinases da Família src/genéticaRESUMO
The STAT4 gene is vital to signaling pathways in the immune response. Immunological alterations are involved in the pathogenesis of endometriosis, and STAT4 polymorphisms may be linked to disease development. This study's aim is to evaluate the possible association between four STAT4 polymorphisms (rs7601754/G > A, rs11889341/C > T, rs7574865/T > G, and rs7582694/C > G) and the pathogenesis of endometriosis in Brazilian women. This case-control study's sample comprised 238 women with endometriosis and 201 healthy, fertile women without endometriosis (which was surgically confirmed). Genotyping was performed using the TaqMan system with a real-time polymerase chain reaction; the genotype, allele, and haplotype frequencies were then compared between groups. A single-polymorphism analysis revealed that the TT genotype of the rs7574865/T > G polymorphism was significantly more frequent in women with minimal or mild endometriosis than in the controls (10% vs. 5%, p = 0.047). The CGAC, GTAT, and GTAC haplotypes were significantly more frequent in the women with endometriosis-related infertility (5.8%, 4.1%, and 2.9%, respectively) than in the controls (2.4%, 1.1%, and 0.8%, respectively; p = 0.020, p = 0.011, and p = 0.032, respectively), but the GGGC and CTAT haplotypes were significantly more prevalent in the control group (34.7% and 13.9%, respectively) than among the infertile group (26.2% and 9.1%, respectively). In addition, the CGAC haplotype was more frequently found in those with minimal or mild endometriosis (6.8%) than in the controls (2.4%, p = 0.009), and the GTAT haplotype was more commonly found in those with moderate or severe disease (3.6%) than in the controls (1.1%, p = 0.028). These findings suggest that STAT4 polymorphisms can influence the pathogenesis of endometriosis.
Assuntos
Endometriose/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Adulto , Alelos , Estudos de Casos e Controles , Endometriose/metabolismo , Endometriose/patologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Haplótipos , Humanos , FenótipoRESUMO
Type 2 reaction (T2R) or erythema nodosum leprosum (ENL), a sudden episode of acute inflammation predominantly affecting lepromatous leprosy patients (LL), characterized by a reduced cellular immune response. This possibly indicates a close relationship between the onset of T2R and the altered frequency, and functional activity of T lymphocytes, particularly of memory subsets. This study performed ex vivo and in vitro characterizations of T cell blood subpopulations from LL patients with or without T2R. In addition, the evaluation of activity of these subpopulations was performed by analyzing the frequency of these cells producing IFN-γ, TNF, and IL-10 by flow cytometry. Furthermore, the expression of transcription factors, for the differentiation of T cells, were analyzed by quantitative real-time polymerase chain reaction. Our results showed an increased frequency of CD8+/TNF+ effector memory T cells (TEM) among T2Rs. Moreover, there was evidence of a reduced frequency of CD4 and CD8+ IFN-γ-producing cells in T2R, and a reduced expression of STAT4 and TBX21. Finally, a significant and positive correlation between bacteriological index (BI) of T2R patients and CD4+/TNF+ and CD4+/IFN-γ+ T cells was observed. Thus, negative correlation between BI and the frequency of CD4+/IL-10+ T cells was noted. These results suggest that CD8+/TNF+ TEM are primarily responsible for the transient alteration in the immune response to Mycobacterium leprae in ENL patients. Thus, our study improves our understanding of pathogenic mechanisms and might suggest new therapeutic approaches for leprosy.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Eritema Nodoso/imunologia , Hanseníase Virchowiana/imunologia , Mycobacterium leprae/patogenicidade , Fator de Necrose Tumoral alfa/imunologia , Adolescente , Adulto , Idoso , Linfócitos T CD4-Positivos/microbiologia , Linfócitos T CD8-Positivos/microbiologia , Estudos de Casos e Controles , Eritema Nodoso/genética , Eritema Nodoso/patologia , Feminino , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Memória Imunológica , Imunofenotipagem , Interferon gama/genética , Interferon gama/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Hanseníase Virchowiana/genética , Hanseníase Virchowiana/patologia , Masculino , Pessoa de Meia-Idade , Mycobacterium leprae/crescimento & desenvolvimento , Mycobacterium leprae/imunologia , Cultura Primária de Células , Fator de Transcrição STAT4/genética , Fator de Transcrição STAT4/imunologia , Transdução de Sinais , Proteínas com Domínio T/genética , Proteínas com Domínio T/imunologia , Fator de Necrose Tumoral alfa/genéticaRESUMO
Background: Mutations in genes affecting interferon-γ (IFN-γ) immunity have contributed to understand the role of IFN-γ in protection against intracellular pathogens. However, inborn errors in STAT4, which controls interleukin-12 (IL-12) responses, have not yet been reported. Our objective was to determine the genetic defect in a family with a history of paracoccidioidomycosis. Methods: Genetic analysis was performed by whole-exome sequencing and Sanger sequencing. STAT4 phosphorylation (pSTAT4) and translocation to the nucleus, IFN-γ release by patient lymphocytes, and microbicidal activity of patient monocytes/macrophages were assessed. The effect on STAT4 function was evaluated by site-directed mutagenesis using a lymphoblastoid B cell line (B-LCL) and U3A cells. Results: A heterozygous missense mutation, c.1952 A>T (p.E651V) in STAT4 was identified in the index patient and her father. Patient's and father's lymphocytes showed reduced pSTAT4, nuclear translocation, and impaired IFN-γ production. Mutant B-LCL and U3A cells also displayed reduced pSTAT4. Patient's and father's peripheral blood mononuclear cells and macrophages demonstrated impaired fungicidal activity compared with those from healthy controls that improved in the presence of recombinant human IFN-γ, but not rhIL-12. Conclusion: Our data suggest autosomal dominant STAT4 deficiency as a novel inborn error of IL-12-dependent IFN-γ immunity associated with susceptibility to paracoccidioidomycosis.
Assuntos
Predisposição Genética para Doença , Interferon gama/deficiência , Subunidade p35 da Interleucina-12/metabolismo , Mutação de Sentido Incorreto , Paracoccidioidomicose/genética , Fator de Transcrição STAT4/genética , Adulto , Idoso , Linhagem Celular , Saúde da Família , Feminino , Genótipo , Heterozigoto , Humanos , Linfócitos/imunologia , Macrófagos/imunologia , Masculino , Análise de Sequência de DNARESUMO
Rheumatoid arthritis (RA) is a systemic autoimmune disease in whose etiology genetic factors are known to play an important role. Among the genes associated with RA, STAT4 could be an important factor in conducting helper T cells toward the pro-inflammatory Th1 and Th17 lineages. The aim of this study is to determine the association of the STAT4 polymorphism rs7574865 with RA, disease activity, and anti-cyclic citrullinated peptide (CCP) antibody levels in a Mexican population. Genotyping was carried out using the Taqman® system from Applied Biosystems in 140 patients with RA and 150 healthy subjects. Disease activity was evaluated by a rheumatologist using the DAS28 and Spanish-HAQ-DI instruments. Anti-CCP levels were determined by ELISA. Associations of the genotypes of rs7574865 with DAS28, HAQ, and anti-CCP antibody levels with RA were determined. Findings showed that the GT and TT genotypes and the T allele from rs7574865 were all associated as risk factors for RA, independently of their anti-CCP status. An association with moderate-to-high disease activity (DAS28 ≥ 3.2) was also found. Additionally, patients with the GT or TT genotypes showed lower HAQ values than those who carried the GG genotype. No differences in anti-CCP antibody levels or DAS28 and genotypes were found. This work supports the association of the STAT4 rs7574865 polymorphism with RA and disease activity, but not with anti-CCP antibody levels in a Mexican population.
Assuntos
Anticorpos/sangue , Artrite Reumatoide/genética , Peptídeos Cíclicos/imunologia , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Adulto , Idoso , Alelos , Artrite Reumatoide/etnologia , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Imunoglobulina G/sangue , Masculino , México , Pessoa de Meia-Idade , Fatores de Risco , Células Th1/citologia , Células Th17/citologiaRESUMO
STAT4 has been consistently associated with several autoimmune diseases, including rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The aim of this study was to determine whether the STAT4 rs7574865G/T polymorphism confers susceptibility for RA and SLE in a sample of Mexican patients. This study included 869 individuals: 415 patients with RA, 128 patients with SLE, and 326 controls. Genotyping using TaqMan probes showed an association between the STAT4 rs7574865G/T polymorphism and RA (GG vs. TT: OR 1.99, p=0.0009; G vs. T: OR 1.42, p=0.0009) and SLE (GG vs. TT: OR 2.98, 0.0003; G vs. T: OR 1.74, p=0.0002). Gender stratification showed an association with RA (GG vs. TT: OR 1.99, 95% CI 1.3-3.1, p=0.002; G vs. T: OR 1.42, 95% CI 1.1-1.8, p=0.002) and SLE (GG vs. TT: OR 3.3, 95% CI 1.7-6.2, p=0.0002; G vs. T: OR 1.8, 95% CI 1.3-2.4, p=0.0002) in women. Thus, the STAT4 rs7574865G/T polymorphism confers risk for RA and SLE in the Mexican population.
Assuntos
Artrite Reumatoide/genética , Lúpus Eritematoso Sistêmico/genética , Fator de Transcrição STAT4/genética , Adulto , Artrite Reumatoide/epidemiologia , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Risco , Fatores SexuaisRESUMO
OBJECTIVE: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a strong genetic component. We undertook the present work to perform the first genome-wide association study on individuals from the Americas who are enriched for Native American heritage. METHODS: We analyzed 3,710 individuals from the US and 4 countries of Latin America who were diagnosed as having SLE, and healthy controls. Samples were genotyped with HumanOmni1 BeadChip. Data on out-of-study controls genotyped with HumanOmni2.5 were also included. Statistical analyses were performed using SNPtest and SNPGWA. Data were adjusted for genomic control and false discovery rate. Imputation was performed using Impute2 and, for classic HLA alleles, HiBag. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: The IRF5-TNPO3 region showed the strongest association and largest OR for SLE (rs10488631: genomic control-adjusted P [Pgcadj ] = 2.61 × 10(-29), OR 2.12 [95% CI 1.88-2.39]), followed by HLA class II on the DQA2-DQB1 loci (rs9275572: Pgcadj = 1.11 × 10(-16), OR 1.62 [95% CI 1.46-1.80] and rs9271366: Pgcadj = 6.46 × 10(-12), OR 2.06 [95% CI 1.71-2.50]). Other known SLE loci found to be associated in this population were ITGAM, STAT4, TNIP1, NCF2, and IRAK1. We identified a novel locus on 10q24.33 (rs4917385: Pgcadj = 1.39 × 10(-8)) with an expression quantitative trait locus (eQTL) effect (Peqtl = 8.0 × 10(-37) at USMG5/miR1307), and several new suggestive loci. SLE risk loci previously identified in Europeans and Asians were corroborated. Local ancestry estimation showed that the HLA allele risk contribution is of European ancestral origin. Imputation of HLA alleles suggested that autochthonous Native American haplotypes provide protection against development of SLE. CONCLUSION: Our results demonstrate that studying admixed populations provides new insights in the delineation of the genetic architecture that underlies autoimmune and complex diseases.