RESUMO
OBJECTIVES: The TYK2 gene encodes a tyrosin kinase which is involved in multiple immune functions. A functional variant of this gene has been identified to play a protective role in multiple autoimmune diseases. The goal of this study was to evaluate the involvement of this variant of TYK2 in vasculitides [giant cell arteritis (GCA), ANCA-associated vasculitis (AAV) and IgA vasculitis (IgAV)] and viral infections [hepatitis C virus (HCV) and human immunodeficiency virus type I (HIV-1)]. METHODS: The study sample was composed of 13,745 European individuals. The genotyping was performed by Immunochip and TaqMan 5' allele discrimination assays and the allele frequencies were compared using PLINK. RESULTS: Although the results obtained did not reach the genome-wide level of significance, p-values at nominal significance were observed, suggesting that the TYK2 variant provides protection against two vasculitides: GCA (p=5.94E-3; OR (95%CI) = 0.56 (0.37-0.85) and AAV (p=6.79E-3; OR (95%CI) = 0.65 (0.47-0.89). However, this variant was not found to be associated with IgAV. No evidence was gained that the TYK2 variant confers susceptibility to HCV and HIV-1 infection. CONCLUSIONS: This is the first study to propose the association between the TYK2 and both GCA and AAV. Our findings also suggest that TYK2 does not play a relevant role in IgAV or in susceptibility to HCV and HVI-1.
Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Arterite de Células Gigantes , Infecções , Alelos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/genética , Frequência do Gene , Predisposição Genética para Doença , Arterite de Células Gigantes/genética , Humanos , Polimorfismo de Nucleotídeo Único , TYK2 QuinaseRESUMO
Next-generation sequencing (NGS) at the HLA-A, -B, -C, -DPA1, -DPB1, -DQA1, -DQB1, -DRB1 and -DRB3/4/5 loci was performed on 282 healthy unrelated individuals from different major regions of Spain. High-resolution HLA genotypes defined by full sequencing of class I loci and extended coverage of class II loci were obtained to determine allele frequencies and also to estimate extended haplotype frequencies. HLA alleles were typed at the highest resolution level (4-field level, 4FL); with exception of a minor deviation in HLA-DPA1, no statistically significant deviations from expected Hardy Weinberg Equilibrium (HWE) proportions were observed for all other HLA loci. This study provides new 4FL-allele and -haplotype frequencies estimated for the first time in the Spanish population. Furthermore, our results describe extended haplotypes (including the less frequently typed HLA-DPA1 and HLA-DQA1 loci) and show distinctive haplotype associations found at 4FL-allele definition in this Spanish population study. The distinctive allelic and haplotypic diversity found at the 4FL reveals the high level of heterozygosity and specific haplotypic associations displayed that were not apparent at 2-field level (2FL). Overall, these results may contribute as a useful reference source for future population studies, for HLA-disease association studies as a healthy control group dataset and for improving donor recruitment strategies of bone marrow registries. HLA genotyping data of this Spanish population cohort was also included in the 17th International Histocompatibility and Immunogenetics Workshop (IHIW) as part of the study of HLA diversity in unrelated worldwide populations using NGS.
Assuntos
Frequência do Gene/genética , Antígenos HLA/genética , Haplótipos/genética , Estudos de Coortes , Éxons/genética , Loci Gênicos , Variação Genética , Genótipo , Heterozigoto , Sequenciamento de Nucleotídeos em Larga Escala , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe II/genética , Teste de Histocompatibilidade , Homozigoto , Humanos , Desequilíbrio de Ligação/genética , Análise de Sequência de DNA , EspanhaRESUMO
BACKGROUND: Hepatitis C virus (HCV) is associated with a higher prevalence of steatosis compared to the general population. AIM: Our aim was to assess the impact of PNPLA3 rs738409 G-allele on steatosis in HCV patients. MATERIAL AND METHODS: We included 474 HCV patients treated with peginterferon plus ribavirin. PNPLA3 rs738409 was genotyped and patients were classified according to alleles and genotypes. Steatosis was detected in 46.4% (220/474). Fibrosis was assessed by Scheuer score. Gene expression was analyzed in Huh7.5 and Huh7 cells using Real Time-PCR. RESULTS: PNPLA3 allele-G was associated with steatosis [54.1% (126/233) vs. 39% (94/241)] (p = 0.0001). In HCV-1, allele-G was related to steatosis [50.6% (82/162) vs. 32.3% (53/164)] (p = 0.001), but did not in HCV-3 [61.9% (26/42) vs. 62% (31/50)] (p = 0.993). PNPLA3 allele-G was associated with steatosis in patients with IL28B-CT/TT [57.7% (82/142) vs. 37.1% (56/151)] (p = 0.0001), but did not in IL28B-CC [47.8% (43/90) vs. 42% (37/88)] (p = 0.442). Independent variables associated with steatosis were: PNPLA3 G-allele [O.R. 1.84 (CI95%: 1.06-3.21); p = 0.007], age [O.R. 1.04 (CI95%: 1.01-1.07); p = 0.017], HCV-genotype 3 [O.R. 2.46 (CI95%: 1.30-4.65); p = 0.006], HOMA > 4 [O.R. 2.72 (CI95%: 1.27-5.82); p = 0.010]. Since PNPLA3 RNA could not be detected on PBMC from HCV patients, an in vitro analysis was performed. Huh7.5 cells infected with JFH1 had a decreased PNPLA3 gene expression (fold inhibition = 3.2 ± 0.2), while Huh7 cells presented increased PNPLA3 gene expression (fold induction = 1.5 ± 0.2). CONCLUSION: PNPLA3 allele-G modulated the development of steatosis, particularly in patients with HCV-1 and IL28B-CT/TT genotype, but was not associated with SVR. Metabolic but not viral steatosis seems to be PNPLA3 regulated. Gene interaction may result in differential PNPLA3 gene expression levels in HCV infection.
Assuntos
Fígado Gorduroso/genética , Hepacivirus/genética , Hepatite C Crônica/genética , Interleucinas/genética , Lipase/genética , Fígado/patologia , Proteínas de Membrana/genética , RNA Viral/genética , Adulto , Antivirais/uso terapêutico , Células Cultivadas , Estudos de Coortes , Estudos Transversais , Quimioterapia Combinada , Fígado Gorduroso/virologia , Feminino , Perfilação da Expressão Gênica , Genótipo , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Interferons , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico , Ribavirina/uso terapêutico , Fatores de Risco , Carga ViralRESUMO
The ubiquitin associated and Src-homology 3 (SH3) domain containing A (UBASH3a) is a suppressor of T-cell receptor signaling, underscoring antigen presentation to T-cells as a critical shared mechanism of diseases pathogenesis. The aim of the present study was to determine whether the UBASH3a gene influence the susceptibility to systemic lupus erythematosus (SLE) in Caucasian populations. We evaluated five UBASH3a polymorphisms (rs2277798, rs2277800, rs9976767, rs13048049 and rs17114930), using TaqMan® allelic discrimination assays, in a discovery cohort that included 906 SLE patients and 1165 healthy controls from Spain. The SNPs that exhibit statistical significance difference were evaluated in a German replication cohort of 360 SLE patients and 379 healthy controls. The case-control analysis in the Spanish population showed a significant association between the rs9976767 and SLE (Pcâ=â9.9E-03 ORâ=â1.21 95%CIâ=â1.07-1.37) and a trend of association for the rs2277798 analysis (Pâ=â0.09 ORâ=â0.9 95%CIâ=â0.79-1.02). The replication in a German cohort and the meta-analysis confirmed that the rs9976767 (Pcâ=â0.02; Pcâ=â2.4E-04, for German cohort and meta-analysis, respectively) and rs2277798 (Pcâ=â0.013; Pcâ=â4.7E-03, for German cohort and meta-analysis, respectively) UBASH3a variants are susceptibility factors for SLE. Finally, a conditional regression analysis suggested that the most likely genetic variation responsible for the association was the rs9976767 polymorphism. Our results suggest that UBASH3a gene plays a role in the susceptibility to SLE. Moreover, our study indicates that UBASH3a can be considered as a common genetic factor in autoimmune diseases.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Lúpus Eritematoso Sistêmico/genética , Alelos , Predisposição Genética para Doença/genética , Genótipo , Humanos , Desequilíbrio de Ligação/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética , Fatores de RiscoRESUMO
The single-nucleotide polymorphism (SNP) rs12979860 near the IL28B gene has been associated with the spontaneous clearance of hepatitis C virus. We sought to determine whether this SNP could be associated with the spontaneous control of human immunodeficiency virus (HIV) infection. We studied the prevalence of the IL28B CC genotype among 53 white HIV controllers, compared with the prevalence among 389 HIV-infected noncontrollers. We found that the IL28B CC genotype was independently associated with spontaneous HIV control (odds ratio [OR], 2.669; P = .017), as were female sex (OR, 7.077; P ≤ .001) and the presence of HLA-B57 and/or B27 (OR, 3.080; P = .017). This result supports the idea that common host mechanisms are involved in the spontaneous control of these 2 chronic infections.
Assuntos
Infecções por HIV/genética , Infecções por HIV/imunologia , Interleucinas/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Adulto , Feminino , Genótipo , Infecções por HIV/virologia , Antígenos HLA-B/genética , Hepatite C Crônica/genética , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Humanos , Interferons , Masculino , Pessoa de Meia-Idade , Carga ViralRESUMO
BACKGROUND: The number of copies of the HLA-DRB1 shared epitope, and the minor alleles of the STAT4 rs7574865 and the PTPN22 rs2476601 polymorphisms have all been linked with an increased risk of developing rheumatoid arthritis. In the present study, we investigated the effects of these genetic variants on disease activity and disability in patients with early arthritis. METHODOLOGY AND RESULTS: We studied 640 patients with early arthritis (76% women; median age, 52 years), recording disease-related variables every 6 months during a 2-year follow-up. HLA-DRB1 alleles were determined by PCR-SSO, while rs7574865 and rs2476601 were genotyped with the Taqman 5' allelic discrimination assay. Multivariate analysis was performed using generalized estimating equations for repeated measures. After adjusting for confounding variables such as gender, age and ACPA, the TT genotype of rs7574865 in STAT4 was associated with increased disease activity (DAS28) as compared with the GG genotype (ß coefficient [95% confidence interval] = 0.42 [0.01-0.83], p = 0.044). Conversely, the presence of the T allele of rs2476601 in PTPN22 was associated with diminished disease activity during follow-up in a dose-dependent manner (CT genotype = -0.27 [-0.56- -0.01], p = 0.042; TT genotype = -0.68 [-1.64- -0.27], p = 0.162). After adjustment for gender, age and disease activity, homozygosity for the T allele of rs7574865 in STAT4 was associated with greater disability as compared with the GG genotype. CONCLUSIONS: Our data suggest that patients with early arthritis who are homozygous for the T allele of rs7574865 in STAT4 may develop a more severe form of the disease with increased disease activity and disability.
Assuntos
Artrite/genética , Genótipo , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT4/genética , Adulto , Idoso , Alelos , Artrite/imunologia , Avaliação da Deficiência , Feminino , Predisposição Genética para Doença , Cadeias HLA-DRB1/genética , Humanos , Masculino , Pessoa de Meia-Idade , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Índice de Gravidade de DoençaRESUMO
OBJECTIVES: To perform fine mapping of the autoimmunity susceptibility gene BLK and identify functional variants involved in systemic lupus erythematosus (SLE). METHODS: Genotyping of 1163 European SLE patients and 1482 controls and imputation were performed covering the BLK gene with 158 single-nucleotide polymorphisms. Logistic regression analysis was done using PLINK and conditional analyses using GENABEL's test score. Transfections of BLK constructs on HEK293 cells containing the novel mutation or the wild type form were analysed for their effect on protein half-life using a protein stability assay, cycloheximide and western blot. CHiP-qPCR for detection of nuclear factor κ B (NFkB) binding. RESULTS: Fine mapping of BLK identified two independent genetic effects with functional consequences: one represented by two tightly linked associated haplotype blocks significantly enriched for NFκB-binding sites and numerous putative regulatory variants whose risk alleles correlated with low BLK mRNA levels. Binding of NFkBp50 and p65 to an associated 1.2 Kb haplotype segment was confirmed. A second independent genetic effect was represented by an Ala71Thr, low-frequency missense substitution with an OR=2.31 (95% CI 1.38 to 3.86). The 71Thr decreased BLK protein half-life. CONCLUSIONS: These results show that rare and common regulatory variants in BLK are involved in disease susceptibility and both, albeit independently, lead to reduced levels of BLK protein.
Assuntos
Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Mutação , Polimorfismo de Nucleotídeo Único , Quinases da Família src/genética , Biomarcadores/metabolismo , Mapeamento Cromossômico , Regulação Enzimológica da Expressão Gênica , Marcadores Genéticos/genética , Genótipo , Células HEK293 , Meia-Vida , Humanos , NF-kappa B/metabolismo , Ligação Proteica , Estabilidade Proteica , Transfecção , Quinases da Família src/metabolismoRESUMO
BACKGROUND: Data on which to base definitive recommendations on the doses and duration of therapy for genotype 3 HCV/HIV-coinfected patients are scarce. We evaluated the efficacy of a lower peginterferon-α 2a dose and a shorter duration of therapy than the current standard of care in genotype 3 HCV/HIV-coinfected patients. METHODS AND FINDINGS: Pilot, open-label, single arm clinical trial which involved 58 Caucasian HCV/HIV-coinfected patients who received weekly 135 µg peginterferon-α 2a plus ribavirin 400 mg twice daily during 20 weeks after attaining undetectable viremia. The relationships between baseline patient-related variables, including IL28B genotype, plasma HCV-RNA, ribavirin dose/kg, peginterferon-α 2a and ribavirin levels with virological responses were analyzed. Only 4 patients showed lack of response and 5 patients dropped out due to adverse events related to the study medication. Overall, sustained virologic response (SVR) rates were 58.3% by intention-to-treat and 71.4% by per protocol analysis, respectively. Among patients with rapid virologic response (RVR), SVR and relapses rates were 92.6% and 7.4%, respectively. No relationships were observed between viral responses and ribavirin dose/kg, peginterferon-α 2a concentrations, ribavirin levels or rs129679860 genotype. CONCLUSIONS: Weekly 135 µg pegIFN-α 2a could be as effective as the standard 180 µg dose, with a very low incidence of severe adverse events. A 24-week treatment duration appears to be appropriate in patients achieving RVR, but extending treatment up to just 20 weeks beyond negativization of viremia is associated with a high relapse rate in those patients not achieving RVR. There was no influence of IL28B genotype on the virological responses. TRIAL REGISTRATION: ClinicalTrials.gov NCT00553930.
Assuntos
Genótipo , Infecções por HIV/complicações , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Interferon-alfa/uso terapêutico , Interleucinas/genética , Polietilenoglicóis/uso terapêutico , Polimorfismo de Nucleotídeo Único , Adulto , Relação Dose-Resposta a Droga , Feminino , Hepatite C Crônica/complicações , Hepatite C Crônica/metabolismo , Humanos , Interferon-alfa/efeitos adversos , Interferon-alfa/farmacocinética , Interferons , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , Polietilenoglicóis/farmacocinética , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapêutico , Ribavirina/farmacocinética , Ribavirina/uso terapêutico , Segurança , Resultado do TratamentoRESUMO
OBJECTIVE: To determine the role of Class II HLAs in SSc patients from Italy and Spain and in SSc patients of Caucasian ancestry. METHODS: Nine hundred and forty-four SSc patients (Italy 392 patients; Spain 452 patients) and 1320 ethnically matched healthy controls (Italy 398 patients; Spain 922 patients) were genotyped up to the fourth digit by PCR with sequence-specific oligonucleotides for HLA-DRB1, DQA1 and DQB1 loci. Patients included 390 ACA-positive and 254 anti-topo I-positive subjects. Associations between SSc or SSc-specific antibodies and HLA alleles or HLA haplotypes were sought via the chi-square test after 10 000-fold permutation testing. A meta-analysis including this study cohort and other Caucasoids samples was also conducted. RESULTS: In both the cohorts, the strongest association was observed between the HLA-DRB1*1104 allele and SSc or anti-topo I antibodies. The HLA-DRB1*1104 -DQA1*0501 -DQB1*0301 haplotype was overrepresented in Italian [odds ratio (OR) = 2.069, 95% asymptotic CIs (CI(95)) 1.486, 2.881; P < 0.001] and in Spanish patients (OR = 6.707, CI(95) 3.974, 11.319; P < 0.001) as well as in anti-topo-positive patients: Italy (OR = 2.642, CI(95) 1.78, 3.924; P < 0.001) and Spain (OR = 20.625, CI(95) 11.536, 36.876; P < 0.001). In both the populations we also identified an additional risk allele (HLA-DQB1*03) and a protective allele (HLA-DQB1*0501) in anti-topo-positive patients. The meta-analysis showed different statistically significant associations, the most interesting being the differential association between HLA-DRB1*01 alleles and ACAs (OR = 1.724, CI(95) 1.482, 2.005; P < 0.001) or topo I antibodies (OR = 0.5, CI(95) 0.384, 0.651; P < 0.001). CONCLUSIONS: We describe multiple robust associations between SSc and HLA Class II antigens in Caucasoids that may help to understand the genetic architecture of SSc.
Assuntos
Antígenos HLA-D/genética , Escleroderma Sistêmico/genética , Autoanticorpos/análise , Estudos de Casos e Controles , Predisposição Genética para Doença , Cadeias alfa de HLA-DQ/genética , Cadeias beta de HLA-DQ/genética , Cadeias HLA-DRB1/genética , Teste de Histocompatibilidade/métodos , Humanos , Itália/epidemiologia , Escleroderma Sistêmico/epidemiologia , Escleroderma Sistêmico/imunologia , Espanha/epidemiologiaRESUMO
OBJECTIVE: The PTPN22 rs2476601 genetic variant has been associated with rheumatoid arthritis (RA) and other autoimmune diseases. Some reports suggest that this single-nucleotide polymorphism (SNP) may not be the only causal variant in the region of PTPN22. Our aim was to identify new independent RA-associated common gene variants in the PTPN22 region. METHODS: We analyzed Wellcome Trust Case-Control Consortium genome-wide association study data for associations in the 397.2 kb PTPN22 region and selected 9 associated SNP (with p < 5 × 10(-3)) for replication and dependence analysis. The replication cohorts comprised 2857 patients with RA and 2994 controls from Spain, Netherlands, and Norway. RESULTS: We found that 6 of the 9 selected SNP were associated in the Spanish cohort. Of these, 4 were also associated in the Dutch and Norwegian cohorts, and all 6 were associated with RA in the combined analysis. Conditional analyses showed that none of these associations was independent of rs2476601. CONCLUSION: The SNP rs2476601 located in the PTPN22 gene is the sole common genetic variant associated with RA in the 1p13.2 region, suggesting that neighbor genes of PTPN22 do not have a major influence in RA.
Assuntos
Artrite Reumatoide/genética , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Artrite Reumatoide/etnologia , Estudos de Casos e Controles , Estudo de Associação Genômica Ampla , Humanos , Países Baixos , Noruega , Fatores de Risco , EspanhaRESUMO
The aim of this study was to determine, through a genome-wide association study (GWAS), the genetic components contributing to different clinical sub-phenotypes of systemic sclerosis (SSc). We considered limited (lcSSc) and diffuse (dcSSc) cutaneous involvement, and the relationships with presence of the SSc-specific auto-antibodies, anti-centromere (ACA), and anti-topoisomerase I (ATA). Four GWAS cohorts, comprising 2,296 SSc patients and 5,171 healthy controls, were meta-analyzed looking for associations in the selected subgroups. Eighteen polymorphisms were further tested in nine independent cohorts comprising an additional 3,175 SSc patients and 4,971 controls. Conditional analysis for associated SNPs in the HLA region was performed to explore their independent association in antibody subgroups. Overall analysis showed that non-HLA polymorphism rs11642873 in IRF8 gene to be associated at GWAS level with lcSSc (Pâ=â2.32×10(-12), ORâ=â0.75). Also, rs12540874 in GRB10 gene (Pâ=â1.27 × 10(-6), ORâ=â1.15) and rs11047102 in SOX5 gene (Pâ=â1.39×10(-7), ORâ=â1.36) showed a suggestive association with lcSSc and ACA subgroups respectively. In the HLA region, we observed highly associated allelic combinations in the HLA-DQB1 locus with ACA (Pâ=â1.79×10(-61), ORâ=â2.48), in the HLA-DPA1/B1 loci with ATA (Pâ=â4.57×10(-76), ORâ=â8.84), and in NOTCH4 with ACA Pâ=â8.84×10(-21), ORâ=â0.55) and ATA (Pâ=â1.14×10(-8), ORâ=â0.54). We have identified three new non-HLA genes (IRF8, GRB10, and SOX5) associated with SSc clinical and auto-antibody subgroups. Within the HLA region, HLA-DQB1, HLA-DPA1/B1, and NOTCH4 associations with SSc are likely confined to specific auto-antibodies. These data emphasize the differential genetic components of subphenotypes of SSc.
Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Escleroderma Sistêmico/genética , Alelos , Autoanticorpos/imunologia , Feminino , Loci Gênicos/genética , Marcadores Genéticos , Antígenos HLA/genética , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único/genética , Escleroderma Sistêmico/classificação , Escleroderma Sistêmico/imunologiaRESUMO
OBJECTIVE: Recently, a functional PTPN22 variant (R263Q; rs33996649) was found to be associated with systemic lupus erythematosus (SLE). This study was undertaken to analyze the influence of this polymorphism on the risk of rheumatoid arthritis (RA). METHODS: RA patients (n = 5,579) were recruited from outpatient clinics from 6 different countries (Spain, New Zealand, the UK, Norway, The Netherlands, and Germany). Healthy controls (n = 5,392) were recruited from the same areas. There was 100% power to detect an effect equivalent to that observed in SLE. Samples were genotyped for the PTPN22 R263Q (rs33996649) and PTPN22 R620W (rs2476601) polymorphisms using a TaqMan 5'-allele discrimination assay. The effect of the R263Q variant was analyzed in isolation and in combination with the effect of R620W, using Unphased and Stata 10 software. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were determined. RESULTS: The minor allele A of PTPN22 R263Q was significantly associated with a lower risk of RA in the pooled analysis of the 6 populations (P = 0.016, Mantel-Haenszel pooled OR 0.80 [95% CI 0.67-0.96]), independent of the effect of the R620W polymorphism. Both polymorphisms had an additive effect. The more RA risk alleles carried (R263Q G allele, R620W T allele), the higher the RA risk (for 2 versus 1 risk allele P = 0.014, OR 1.28 [95% CI 1.05-1.55], for 3 versus 1 risk allele P = 6.67 × 10(-11) , OR 2.01 [1.63-2.48], and for 4 versus 1 risk allele P = 6.50 × 10(-11) , OR 3.55 [2.42-5.20]). CONCLUSION: Our findings indicate that the minor allele of the PTPN22 R263Q polymorphism is associated with a lower risk of RA. This association is independent of the well-established association between PTPN22 R620W and RA. Both polymorphisms have an additive effect on the risk of RA.
Assuntos
Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , População Branca/genética , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , MasculinoRESUMO
We assessed the contribution of four baseline markers-HLA-DRB1 shared epitope (SE), -308 tumor necrosis factor α gene promoter polymorphism, rheumatoid factor, and anticitrullinated peptide antibodies-for predicting persistent activity (DAS28 score ≥2.6) after one year of followup in a cohort of 201 patients with recent-onset rheumatoid arthritis (RA) or undifferentiated arthritis (UA) aged 16 years or older who had a 4-week to 12-month history of swelling of at least two joints. Patients had not been previously treated with corticosteroids or disease-modifying antirheumatic drugs (DMARD). In the best logistic regression model, only two variables were retained: SE positivity and number of DMARD administered (area under the curve = 76.4%; 95% CI: 69.2%, 84.4%; P < 0.001). The best linear regression model also included these two variables, explaining only 22.5% of the variability of DAS28 score. In this study, given an equal number of DMARD administered, the probability of persistent activity in patients with recent-onset RA or UA was significantly influenced by SE presence.
RESUMO
OBJECTIVES: The aim of this study was to confirm the influence of TNFSF4 polymorphisms on systemic sclerosis (SSc) susceptibility and phenotypic features. METHODS: A total of 8 European populations of Caucasian ancestry were included, comprising 3014 patients with SSc and 3125 healthy controls. Four genetic variants of TNFSF4 gene promoter (rs1234314, rs844644, rs844648 and rs12039904) were selected as genetic markers. RESULTS: A pooled analysis revealed the association of rs1234314 and rs12039904 polymorphisms with SSc (OR 1.15, 95% CI 1.02 to 1.31; OR 1.18, 95% CI 1.08 to 1.29, respectively). Significant association of the four tested variants with patients with limited cutaneous SSc (lcSSc) was revealed (rs1234314 OR 1.22, 95% CI 1.07 to 1.38; rs844644 OR 0.91, 95% CI 0.83 to 0.99; rs844648 OR 1.10, 95% CI 1.01 to 1.20 and rs12039904 OR 1.20, 95% CI 1.09 to 1.33). Association of rs1234314, rs844648 and rs12039904 minor alleles with patients positive for anti-centromere antibodies (ACA) remained significant (OR 1.23, 95% CI 1.10 to 1.37; OR 1.12, 95% CI 1.01 to 1.25; OR 1.22, 95% CI 1.07 to 1.38, respectively). Haplotype analysis confirmed a protective haplotype associated with SSc, lcSSc and ACA positive subgroups (OR 0.88, 95% CI 0.82 to 0.96; OR 0.88, 95% CI 0.80 to 0.96; OR 0.86, 95% CI 0.77 to 0.97, respectively) and revealed a new risk haplotype associated with the same groups of patients (OR 1.14, 95% CI 1.03 to 1.26; OR 1.20, 95% CI 1.08 to 1.35; OR 1.23, 95% CI 1.07 to 1.42, respectively). CONCLUSIONS: The data confirm the influence of TNFSF4 polymorphisms in SSc genetic susceptibility, especially in subsets of patients positive for lcSSc and ACA.
Assuntos
Ligante OX40/genética , Polimorfismo de Nucleotídeo Único , Escleroderma Sistêmico/genética , Estudos de Casos e Controles , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Regiões Promotoras Genéticas/genéticaRESUMO
OBJECTIVE: Costimulatory receptor CD226 plays an important role in T cell activation, differentiation, and cytotoxicity. This study was undertaken to investigate the genetic association of CD226 with susceptibility to systemic lupus erythematosus (SLE) and to assess the functional implications of this association. METHODS: Twelve tag single-nucleotide polymorphisms (SNPs) in CD226 were typed in 1,163 SLE patients and 1,482 healthy control subjects from Europe or of European ancestry. Analyses of association were performed by single-marker Cochran-Mantel-Haenszel meta-analysis, followed by haplotype analysis. Gene expression was analyzed by quantitative real-time polymerase chain reaction analyses of RNA from peripheral blood mononuclear cells, and by fluorescence-activated cell sorter analysis. To study the functional impact of the associated variants, luciferase reporter constructs containing different portions of the 3'-untranslated region (3'-UTR) of the gene were prepared and used in transfection experiments. RESULTS: A 3-variant haplotype, rs763361;rs34794968;rs727088 (ATC), in the last exon of CD226 was associated with SLE (P = 1.3 × 10(-4) , odds ratio 1.24, 95% confidence interval 1.11-1.38). This risk haplotype correlated with low CD226 transcript expression and low CD226 protein levels on the surface of CD4+ and CD8+ T cells and natural killer T (NKT) cells. NK cells expressed high levels of CD226, but this expression was independent of the haplotype. Reporter assays with deletion constructs indicated that only the presence of rs727088 could account for the differences in the levels of luciferase transcripts. CONCLUSION: This study identified an association of CD226 with SLE in individuals of European ancestry. These data support the importance of the 3'-UTR SNP rs727088 in the regulation of CD226 transcription both in T cells and in NKT cells.
Assuntos
Regiões 3' não Traduzidas/genética , Antígenos de Diferenciação de Linfócitos T/genética , Lúpus Eritematoso Sistêmico/genética , Linfócitos T/imunologia , Regiões 3' não Traduzidas/imunologia , Alelos , Antígenos de Diferenciação de Linfócitos T/imunologia , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Haplótipos , Humanos , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Polimorfismo de Nucleotídeo Único , População Branca/genéticaRESUMO
Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of the skin and internal organs that leads to profound disability and premature death. To identify new SSc susceptibility loci, we conducted the first genome-wide association study in a population of European ancestry including a total of 2,296 individuals with SSc and 5,171 controls. Analysis of 279,621 autosomal SNPs followed by replication testing in an independent case-control set of European ancestry (2,753 individuals with SSc (cases) and 4,569 controls) identified a new susceptibility locus for systemic sclerosis at CD247 (1q22-23, rs2056626, P = 2.09 x 10(-7) in the discovery samples, P = 3.39 x 10(-9) in the combined analysis). Additionally, we confirm and firmly establish the role of the MHC (P = 2.31 x 10(-18)), IRF5 (P = 1.86 x 10(-13)) and STAT4 (P = 3.37 x 10(-9)) gene regions as SSc genetic risk factors.
Assuntos
Complexo CD3/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Escleroderma Sistêmico/genética , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de RiscoRESUMO
OBJECTIVE: To study the value of HLA-DRB1 shared epitope (SE), -308 tumor necrosis factor-alpha (TNF-alpha) gene promoter polymorphism, rheumatoid factor (RF), anti-citrullinated peptide antibodies (anti-CCP), and baseline erosions for predicting radiological outcome at 1 year in patients with recent-onset rheumatoid arthritis (RA). METHODS: Radiological damage was assessed by radiographs at baseline and at 1 year in an inception cohort of 134 RA patients with disease durationAssuntos
Artrite Reumatoide/diagnóstico por imagem
, Autoanticorpos/sangue
, Antígenos HLA-DR/imunologia
, Peptídeos Cíclicos/imunologia
, Polimorfismo de Nucleotídeo Único
, Fator Reumatoide/imunologia
, Fator de Necrose Tumoral alfa/genética
, Antirreumáticos/uso terapêutico
, Artrite Reumatoide/genética
, Artrite Reumatoide/imunologia
, Artrografia
, Biomarcadores/sangue
, Ensaio de Imunoadsorção Enzimática
, Epitopos/imunologia
, Feminino
, Predisposição Genética para Doença
, Cadeias HLA-DRB1
, Humanos
, Masculino
, Pessoa de Meia-Idade
, Valor Preditivo dos Testes
, Prognóstico
, Regiões Promotoras Genéticas
, Estudos Prospectivos
RESUMO
BACKGROUND: Production of antibodies against donor-specific antigens is one of the central mechanisms of allograft rejection. This antibody-mediated rejection (AMR) is evidenced by the presence of circulating donor-specific antibodies and deposition of complement component C4d on renal endothelium. Although anti-human leukocyte antigen (HLA) antibodies account for a high proportion of AMR, in many cases anti-HLA antibodies cannot be demonstrated. In liver transplant, antibodies against glutathione-S-transferase T1 (GSTT1) expressed on the graft may induce an antibody response leading to a severe graft dysfunction. In addition, presence of antibodies against major-histocompatibility-complex class I chain-related gene A (MICA) has been associated with a poor graft survival in kidney transplantation. METHODS: Pre- and posttransplantation sera from 19 patients fulfilling the criteria for AMR including C4d deposition in renal biopsies were included. Donor-specific antibodies against HLA-I and -II and MICA were studied using Luminex. Anti-GSTT1 antibodies were analyzed by indirect immunofluorescence and by an ELISA method. A control group of 39 patients with graft dysfunction negative for C4d was also included. RESULTS: At the time of the biopsy, 4 (21%) patients had only anti-HLA class I antibodies; 3 (15.8%) had anti-GSTT1, 2 (10.5%) had anti-HLA-class II, and 2 (10.5%) had anti-MICA; four patients had combination of antibodies: HLA-I + MICA (n=1), HLA-I + GSTT1 (n=2), and GSTT1+MICA (n=1). No antibodies were found in 4 (21%) patients. In total, 6 (31.6%) C4d+ patients had anti-GSTT1 antibodies, whereas, among the 39 C4d-negative patients, only 3 (7.7%) had anti-GSTT1 antibodies (P=0.027). CONCLUSION: Besides anti-HLA antibodies, donor-specific antibodies against MICA and GSTT1 antigens could be responsible for the occurrence of antibody-mediated kidney graft rejection.