RESUMEN
BACKGROUND: Disabling pansclerotic morphea (DPM) is a rare systemic inflammatory disorder, characterized by poor wound healing, fibrosis, cytopenias, hypogammaglobulinemia, and squamous-cell carcinoma. The cause is unknown, and mortality is high. METHODS: We evaluated four patients from three unrelated families with an autosomal dominant pattern of inheritance of DPM. Genomic sequencing independently identified three heterozygous variants in a specific region of the gene that encodes signal transducer and activator of transcription 4 (STAT4). Primary skin fibroblast and cell-line assays were used to define the functional nature of the genetic defect. We also assayed gene expression using single-cell RNA sequencing of peripheral-blood mononuclear cells to identify inflammatory pathways that may be affected in DPM and that may respond to therapy. RESULTS: Genome sequencing revealed three novel heterozygous missense gain-of-function variants in STAT4. In vitro, primary skin fibroblasts showed enhanced interleukin-6 secretion, with impaired wound healing, contraction of the collagen matrix, and matrix secretion. Inhibition of Janus kinase (JAK)-STAT signaling with ruxolitinib led to improvement in the hyperinflammatory fibroblast phenotype in vitro and resolution of inflammatory markers and clinical symptoms in treated patients, without adverse effects. Single-cell RNA sequencing revealed expression patterns consistent with an immunodysregulatory phenotype that were appropriately modified through JAK inhibition. CONCLUSIONS: Gain-of-function variants in STAT4 caused DPM in the families that we studied. The JAK inhibitor ruxolitinib attenuated the dermatologic and inflammatory phenotype in vitro and in the affected family members. (Funded by the American Academy of Allergy, Asthma, and Immunology Foundation and others.).
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Enfermedades Autoinmunes , Fármacos Dermatológicos , Quinasas Janus , Esclerodermia Sistémica , Quinasas Janus/antagonistas & inhibidores , Nitrilos , Pirazoles/uso terapéutico , Pirazoles/farmacología , Pirimidinas , Esclerodermia Sistémica/tratamiento farmacológico , Esclerodermia Sistémica/genética , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/genética , Mutación Missense , Mutación con Ganancia de Función , Fármacos Dermatológicos/uso terapéutico , Antiinflamatorios/uso terapéuticoRESUMEN
OBJECTIVES: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe, delayed hypersensitivity reaction (DHR). We observed DRESS to inhibitors of interleukin 1 (IL-1) or IL-6 in a small group of patients with Still's disease with atypical lung disease. We sought to characterise features of patients with Still's disease with DRESS compared with drug-tolerant Still's controls. We analysed human leucocyte antigen (HLA) alleles for association to inhibitor-related DHR, including in a small Kawasaki disease (KD) cohort. METHODS: In a case/control study, we collected a multicentre series of patients with Still's disease with features of inhibitor-related DRESS (n=66) and drug-tolerant Still's controls (n=65). We retrospectively analysed clinical data from all Still's subjects and typed 94/131 for HLA. European Still's-DRESS cases were ancestry matched to International Childhood Arthritis Genetics Consortium paediatric Still's cases (n=550) and compared for HLA allele frequencies. HLA association also was analysed using Still's-DRESS cases (n=64) compared with drug-tolerant Still's controls (n=30). KD subjects (n=19) were similarly studied. RESULTS: Still's-DRESS features included eosinophilia (89%), AST-ALT elevation (75%) and non-evanescent rash (95%; 88% involving face). Macrophage activation syndrome during treatment was frequent in Still's-DRESS (64%) versus drug-tolerant Still's (3%; p=1.2×10-14). We found striking enrichment for HLA-DRB1*15 haplotypes in Still's-DRESS cases versus INCHARGE Still's controls (p=7.5×10-13) and versus self-identified, ancestry-matched Still's controls (p=6.3×10-10). In the KD cohort, DRB1*15:01 was present only in those with suspected anakinra reactions. CONCLUSIONS: DRESS-type reactions occur among patients treated with IL-1/IL-6 inhibitors and strongly associate with common HLA-DRB1*15 haplotypes. Consideration of preprescription HLA typing and vigilance for serious reactions to these drugs are warranted.
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Antirreumáticos/efectos adversos , Cadenas HLA-DRB1/genética , Hipersensibilidad Tardía/genética , Enfermedad de Still del Adulto/tratamiento farmacológico , Enfermedad de Still del Adulto/genética , Adulto , Alelos , Estudios de Casos y Controles , Síndrome de Hipersensibilidad a Medicamentos/genética , Síndrome de Hipersensibilidad a Medicamentos/inmunología , Tolerancia a Medicamentos/genética , Femenino , Cadenas HLA-DRB1/inmunología , Haplotipos , Humanos , Hipersensibilidad Tardía/inmunología , Interleucina-1/antagonistas & inhibidores , Interleucina-6/antagonistas & inhibidores , Masculino , Síndrome Mucocutáneo Linfonodular/tratamiento farmacológico , Síndrome Mucocutáneo Linfonodular/genética , Estudios Retrospectivos , Enfermedad de Still del Adulto/inmunologíaRESUMEN
OBJECTIVE: Deficiency of adenosine deaminase 2 (DADA2) is a monogenic form of vasculitis that can resemble polyarteritis nodosa (PAN). This study was undertaken to identify potential disease-causing sequence variants in ADA2 in patients with idiopathic PAN, granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA). METHODS: Patients with idiopathic PAN (n = 118) and patients with GPA or MPA (n = 1,107) were screened for rare nonsynonymous variants in ADA2 using DNA sequencing methods. ADA-2 enzyme activity was assessed in selected serum samples. RESULTS: Nine of 118 patients with PAN (7.6%) were identified as having rare nonsynonymous variants in ADA2. Four patients (3.4%) were biallelic for pathogenic or likely pathogenic variants, and 5 patients (4.2%) were monoallelic carriers for 3 variants of uncertain significance and 2 likely pathogenic variants. Serum samples from 2 patients with PAN with biallelic variants were available and showed markedly reduced ADA-2 enzyme activity. ADA-2 enzyme testing of 86 additional patients revealed 1 individual with strongly reduced ADA-2 activity without detectable pathogenic variants. Patients with PAN and biallelic variants in ADA2 were younger at diagnosis than patients with 1 or no variant in ADA2, with no other clinical differences noted. None of the patients with GPA or MPA carried biallelic variants in ADA2. CONCLUSION: A subset of patients with idiopathic PAN meet genetic criteria for DADA2. Given that tumor necrosis factor inhibition is efficacious in DADA2 but is not conventional therapy for PAN, these findings suggest that ADA-2 testing should strongly be considered in patients with hepatitis B virus-negative idiopathic PAN.
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Adenosina Desaminasa/genética , Granulomatosis con Poliangitis/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Poliangitis Microscópica/genética , Poliarteritis Nudosa/genética , Adenosina Desaminasa/deficiencia , Adenosina Desaminasa/metabolismo , Adolescente , Adulto , Anciano , Estudios de Cohortes , Femenino , Pruebas Genéticas , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Péptidos y Proteínas de Señalización Intercelular/deficiencia , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Masculino , Persona de Mediana Edad , Poliarteritis Nudosa/metabolismo , Análisis de Secuencia de ADN , Adulto JovenRESUMEN
Sarcoidosis is a genetically complex systemic inflammatory disease that affects multiple organs. We present a GWAS of a Japanese cohort (700 sarcoidosis cases and 886 controls) with replication in independent samples from Japan (931 cases and 1,042 controls) and the Czech Republic (265 cases and 264 controls). We identified three loci outside the HLA complex, CCL24, STYXL1-SRRM3, and C1orf141-IL23R, which showed genome-wide significant associations (P < 5.0 × 10-8) with sarcoidosis; CCL24 and STYXL1-SRRM3 were novel. The disease-risk alleles in CCL24 and IL23R were associated with reduced CCL24 and IL23R expression, respectively. The disease-risk allele in STYXL1-SRRM3 was associated with elevated POR expression. These results suggest that genetic control of CCL24, POR, and IL23R expression contribute to the pathogenesis of sarcoidosis. We speculate that the CCL24 risk allele might be involved in a polarized Th1 response in sarcoidosis, and that POR and IL23R risk alleles may lead to diminished host defense against sarcoidosis pathogens.
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Quimiocina CCL24/genética , Sistema Enzimático del Citocromo P-450/genética , Predisposición Genética a la Enfermedad , Receptores de Interleucina/genética , Sarcoidosis/etiología , Alelos , Quimiocina CCL24/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Femenino , Estudios de Asociación Genética , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Japón , Masculino , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Receptores de Interleucina/metabolismo , Sarcoidosis/diagnóstico , Sarcoidosis/metabolismoRESUMEN
Familial Mediterranean fever (FMF) is an autoinflammatory disease caused by homozygous or compound heterozygous gain-of-function mutations in MEFV, which encodes pyrin, an inflammasome protein. Heterozygous carrier frequencies for multiple MEFV mutations are high in several Mediterranean populations, suggesting that they confer selective advantage. Among 2,313 Turkish people, we found extended haplotype homozygosity flanking FMF-associated mutations, indicating evolutionarily recent positive selection of FMF-associated mutations. Two pathogenic pyrin variants independently arose >1,800 years ago. Mutant pyrin interacts less avidly with Yersinia pestis virulence factor YopM than with wild-type human pyrin, thereby attenuating YopM-induced interleukin (IL)-1ß suppression. Relative to healthy controls, leukocytes from patients with FMF harboring homozygous or compound heterozygous mutations and from asymptomatic heterozygous carriers released heightened IL-1ß specifically in response to Y. pestis. Y. pestis-infected MefvM680I/M680I FMF knock-in mice exhibited IL-1-dependent increased survival relative to wild-type knock-in mice. Thus, FMF mutations that were positively selected in Mediterranean populations confer heightened resistance to Y. pestis.
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Resistencia a la Enfermedad/genética , Fiebre Mediterránea Familiar/genética , Peste , Pirina/genética , Selección Genética/genética , Animales , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/metabolismo , Resistencia a la Enfermedad/inmunología , Haplotipos , Humanos , Inflamasomas/inmunología , Inflamasomas/metabolismo , Ratones , Ratones Endogámicos C57BL , Mutación , Peste/inmunología , Peste/metabolismo , Pirina/inmunología , Pirina/metabolismo , Turquía , Factores de Virulencia/inmunología , Factores de Virulencia/metabolismo , Yersinia pestisRESUMEN
Periodic fever, aphthous stomatitis, pharyngitis, and cervical adenitis (PFAPA) syndrome is the most common periodic fever syndrome in children. The disease appears to cluster in families, but the pathogenesis is unknown. We queried two European-American cohorts and one Turkish cohort (total n = 231) of individuals with PFAPA for common variants previously associated with two other oropharyngeal ulcerative disorders, Behçet's disease and recurrent aphthous stomatitis. In a metaanalysis, we found that a variant upstream of IL12A (rs17753641) is strongly associated with PFAPA (OR 2.13, P = 6 × 10-9). We demonstrated that monocytes from individuals who are heterozygous or homozygous for this risk allele produce significantly higher levels of IL-12p70 upon IFN-γ and LPS stimulation than those from individuals without the risk allele. We also found that variants near STAT4, IL10, and CCR1-CCR3 were significant susceptibility loci for PFAPA, suggesting that the pathogenesis of PFAPA involves abnormal antigen-presenting cell function and T cell activity and polarization, thereby implicating both innate and adaptive immune responses at the oropharyngeal mucosa. Our results illustrate genetic similarities among recurrent aphthous stomatitis, PFAPA, and Behçet's disease, placing these disorders on a common spectrum, with recurrent aphthous stomatitis on the mild end, Behçet's disease on the severe end, and PFAPA intermediate. We propose naming these disorders Behçet's spectrum disorders to highlight their relationship. HLA alleles may be factors that influence phenotypes along this spectrum as we found new class I and II HLA associations for PFAPA distinct from Behçet's disease and recurrent aphthous stomatitis.
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Síndrome de Behçet/genética , Fiebre/genética , Predisposición Genética a la Enfermedad , Linfadenitis/genética , Faringitis/genética , Estomatitis Aftosa/genética , Alelos , Síndrome de Behçet/inmunología , Niño , Estudios de Cohortes , Fiebre/inmunología , Genes MHC Clase I/genética , Genes MHC Clase I/inmunología , Genes MHC Clase II/genética , Genes MHC Clase II/inmunología , Sitios Genéticos/inmunología , Humanos , Linfadenitis/inmunología , Faringitis/inmunología , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Estomatitis Aftosa/inmunología , SíndromeRESUMEN
Systemic sclerosis (SSc) is a clinically heterogeneous autoimmune disease characterized by mutually exclusive autoantibodies directed against distinct nuclear antigens. We examined HLA associations in SSc and its autoantibody subsets in a large, newly recruited African American (AA) cohort and among European Americans (EA). In the AA population, the African ancestry-predominant HLA-DRB1*08:04 and HLA-DRB1*11:02 alleles were associated with overall SSc risk, and the HLA-DRB1*08:04 allele was strongly associated with the severe antifibrillarin (AFA) antibody subset of SSc (odds ratio = 7.4). These African ancestry-predominant alleles may help explain the increased frequency and severity of SSc among the AA population. In the EA population, the HLA-DPB1*13:01 and HLA-DRB1*07:01 alleles were more strongly associated with antitopoisomerase (ATA) and anticentromere antibody-positive subsets of SSc, respectively, than with overall SSc risk, emphasizing the importance of HLA in defining autoantibody subtypes. The association of the HLA-DPB1*13:01 allele with the ATA+ subset of SSc in both AA and EA patients demonstrated a transancestry effect. A direct correlation between SSc prevalence and HLA-DPB1*13:01 allele frequency in multiple populations was observed (r = 0.98, P = 3 × 10-6). Conditional analysis in the autoantibody subsets of SSc revealed several associated amino acid residues, mostly in the peptide-binding groove of the class II HLA molecules. Using HLA α/ß allelic heterodimers, we bioinformatically predicted immunodominant peptides of topoisomerase 1, fibrillarin, and centromere protein A and discovered that they are homologous to viral protein sequences from the Mimiviridae and Phycodnaviridae families. Taken together, these data suggest a possible link between HLA alleles, autoantibodies, and environmental triggers in the pathogenesis of SSc.
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Autoanticuerpos/inmunología , Autoantígenos/genética , Antígenos HLA/genética , Imitación Molecular/inmunología , Esclerodermia Sistémica/genética , Negro o Afroamericano/genética , Alelos , Secuencia de Aminoácidos/genética , Antígenos Virales/genética , Antígenos Virales/inmunología , Autoantígenos/inmunología , Biología Computacional , Conjuntos de Datos como Asunto , Femenino , Predisposición Genética a la Enfermedad , Antígenos HLA/inmunología , Humanos , Masculino , Mimiviridae/inmunología , Phycodnaviridae/inmunología , Estructura Secundaria de Proteína/genética , Medición de Riesgo , Esclerodermia Sistémica/epidemiología , Esclerodermia Sistémica/inmunología , Homología de Secuencia de Aminoácido , Población Blanca/genéticaRESUMEN
OBJECTIVES: We investigated a Turkish family with multiple patients presenting with familial Mediterranean fever (FMF) and Behçet's disease (BD)-like manifestations. The index case and the two daughters with Behçet-like disease, were previously found to have a TNFAIP3 frameshift mutation. The high number of affected cases in this expanded family could be consistent with a dominantly inherited inflammatory disease, although some individuals had clinical features more consistent with recessively inherited FMF. We sequenced DNA from members of this family to determine whether the TNFAIP3 frameshift mutation and/or MEFV variants could explain this autoinflammatory disease pedigree. METHODS: Patients were clinically diagnosed to have FMF or BD. Sanger sequence targeting TNFAIP3 exon 5 and MEFV exon 10 was carried out. RESULTS: The symptomatic mother of the index case and her affected maternal uncle had compound heterozygous FMF-associated MEFV mutations, p.Met680Ile and p.Arg761His. Two affected daughters of the maternal uncle also had compound heterozygous FMF-associated mutations, p.Met680Ile and p.Val726Ala. The index case and her two affected daughters had a TNFAIP3 frameshift mutation (c.799delG; p.Pro268Leufs*19), which is consistent with their HA20 diagnosis, and also carried a heterozygous MEFV p.Arg761His mutation. CONCLUSIONS: Autoinflammatory disease manifestations in a Turkish family with multiple affected cases could be explained by co-inheritance of pathogenic MEFV variants and a heterozygous HA20-associated mutation. FMF-associated p.Arg761His allele carried with the loss of function TNFAIP3 mutation by all three HA20 patients may contribute to their autoinflammatory phenotype and could also be responsible for their favourable response to colchicine.
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Síndrome de Behçet , Fiebre Mediterránea Familiar , Mutación/genética , Síndrome de Behçet/genética , Fiebre Mediterránea Familiar/genética , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Haploinsuficiencia , Heterocigoto , Humanos , Pirina , TurquíaRESUMEN
OBJECTIVE: Whole-exome sequencing (WES) studies in systemic sclerosis (SSc) patients of European American (EA) ancestry have identified variants in the ATP8B4 gene and enrichment of variants in genes in the extracellular matrix (ECM)-related pathway that increase SSc susceptibility. This study was undertaken to evaluate the association of the ATP8B4 gene and the ECM-related pathway with SSc in a cohort of African American (AA) patients. METHODS: SSc patients of AA ancestry were enrolled from 23 academic centers across the US under the Genome Research in African American Scleroderma Patients consortium. Unrelated AA individuals without serologic evidence of autoimmunity who were enrolled in the Howard University Family Study were used as unaffected controls. Functional variants in genes reported in the 2 WES studies in EA patients with SSc were selected for gene association testing using the optimized sequence kernel association test (SKAT-O) and pathway analysis by Ingenuity Pathway Analysis in 379 patients and 411 controls. RESULTS: Principal components analysis demonstrated that the patients and controls had similar ancestral backgrounds, with roughly equal proportions of mean European admixture. Using SKAT-O, we examined the association of individual genes that were previously reported in EA patients and none remained significant, including ATP8B4 (P = 0.98). However, we confirmed the previously reported association of the ECM-related pathway with enrichment of variants within the COL13A1, COL18A1, COL22A1, COL4A3, COL4A4, COL5A2, PROK1, and SERPINE1 genes (corrected P = 1.95 × 10-4 ). CONCLUSION: In the largest genetic study in AA patients with SSc to date, our findings corroborate the role of functional variants that aggregate in a fibrotic pathway and increase SSc susceptibility.
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Negro o Afroamericano/genética , Redes Reguladoras de Genes/genética , Predisposición Genética a la Enfermedad/etnología , Esclerodermia Sistémica/etnología , Esclerodermia Sistémica/genética , Adenosina Trifosfatasas/genética , Adulto , Proteínas de la Matriz Extracelular/genética , Femenino , Variación Genética , Humanos , Masculino , Persona de Mediana Edad , Análisis de Componente Principal , Población Blanca/genética , Secuenciación del ExomaRESUMEN
OBJECTIVE: To determine whether systemic juvenile idiopathic arthritis (JIA) susceptibility loci that were identified by candidate gene studies demonstrate association with systemic JIA in the largest study population assembled to date. METHODS: Single-nucleotide polymorphisms (SNPs) from 11 previously reported systemic JIA risk loci were examined for association in 9 populations, including 770 patients with systemic JIA and 6,947 controls. The effect of systemic JIA-associated SNPs on gene expression was evaluated in silico in paired whole genome and RNA sequencing data from the lymphoblastoid cell lines (LCLs) of 373 European subjects from the 1000 Genomes Project. Responses of systemic JIA-associated SNPs to anakinra treatment were evaluated in 38 US patients for whom treatment response data were available. RESULTS: We found no association between the previously reported 26 SNPs and systemic JIA. Expanded analysis of the regions containing the 26 SNPs revealed only 1 significant association: the promoter region of IL1RN (P < 1 × 10-4 ). Systemic JIA-associated SNPs correlated with IL1RN expression in LCLs, with an inverse correlation between systemic JIA risk and IL1RN expression. The presence of homozygous IL1RN high expression alleles correlated strongly with a lack of response to anakinra therapy (odds ratio 28.7 [95% confidence interval 3.2-255.8]). CONCLUSION: In our study, IL1RN was the only candidate locus associated with systemic JIA. The implicated SNPs are among the strongest known determinants of IL1RN and interleukin-1 receptor antagonist levels, linking low expression with increased systemic JIA risk. Homozygous high expression alleles predicted nonresponsiveness to anakinra therapy, making them ideal candidate biomarkers to guide systemic JIA treatment. This study is an important first step toward the personalized treatment of systemic JIA.
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Antirreumáticos/farmacología , Artritis Juvenil/genética , Predisposición Genética a la Enfermedad/genética , Proteína Antagonista del Receptor de Interleucina 1/farmacología , Alelos , Artritis Juvenil/tratamiento farmacológico , Estudios de Casos y Controles , Niño , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Proteína Antagonista del Receptor de Interleucina 1/efectos de los fármacos , Proteína Antagonista del Receptor de Interleucina 1/genética , Masculino , Oportunidad Relativa , Variantes Farmacogenómicas/efectos de los fármacos , Variantes Farmacogenómicas/genética , Polimorfismo de Nucleótido Simple/efectos de los fármacos , Polimorfismo de Nucleótido Simple/genética , Regiones Promotoras Genéticas/genéticaRESUMEN
OBJECTIVES: To characterise the clinical features, immune manifestations and molecular mechanisms in a recently described autoinflammatory disease caused by mutations in TRNT1, a tRNA processing enzyme, and to explore the use of cytokine inhibitors in suppressing the inflammatory phenotype. METHODS: We studied nine patients with biallelic mutations in TRNT1 and the syndrome of congenital sideroblastic anaemia with immunodeficiency, fevers and developmental delay (SIFD). Genetic studies included whole exome sequencing (WES) and candidate gene screening. Patients' primary cells were used for deep RNA and tRNA sequencing, cytokine profiling, immunophenotyping, immunoblotting and electron microscopy (EM). RESULTS: We identified eight mutations in these nine patients, three of which have not been previously associated with SIFD. Three patients died in early childhood. Inflammatory cytokines, mainly interleukin (IL)-6, interferon gamma (IFN-γ) and IFN-induced cytokines were elevated in the serum, whereas tumour necrosis factor (TNF) and IL-1ß were present in tissue biopsies of patients with active inflammatory disease. Deep tRNA sequencing of patients' fibroblasts showed significant deficiency of mature cytosolic tRNAs. EM of bone marrow and skin biopsy samples revealed striking abnormalities across all cell types and a mix of necrotic and normal-appearing cells. By immunoprecipitation, we found evidence for dysregulation in protein clearance pathways. In 4/4 patients, treatment with a TNF inhibitor suppressed inflammation, reduced the need for blood transfusions and improved growth. CONCLUSIONS: Mutations of TRNT1 lead to a severe and often fatal syndrome, linking protein homeostasis and autoinflammation. Molecular diagnosis in early life will be crucial for initiating anti-TNF therapy, which might prevent some of the severe disease consequences.
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Anemia Sideroblástica/genética , Antiinflamatorios/uso terapéutico , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Síndromes de Inmunodeficiencia/genética , Mutación , Nucleotidiltransferasas/genética , ARN de Transferencia/genética , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adulto , Anemia Sideroblástica/sangre , Niño , Preescolar , Citocinas/sangre , Citocinas/genética , Discapacidades del Desarrollo/genética , Femenino , Enfermedades Genéticas Ligadas al Cromosoma X/sangre , Humanos , Inmunofenotipificación , Masculino , Linaje , Fenotipo , Factor de Necrosis Tumoral alfa/análisis , Secuenciación del ExomaRESUMEN
OBJECTIVE: To identify a genetic cause of early-onset systemic lupus erythematosus (SLE) in a large consanguineous family from Turkey and to study the mechanisms of the disease. METHODS: We performed whole-exome sequencing and single-nucleotide polymorphism array genotyping in family members with and without SLE. Protein and gene expression, cytokine profile, neutrophil extracellular trap (NET) formation, and presence of low-density granulocytes were evaluated in patient primary cells and serum samples. RESULTS: We identified a novel, homozygous, loss-of-function mutation (p.Pro445Leufs*11) in the C1R gene. Using the Sanger method of DNA sequencing in 14 family members, we confirmed the presence of the mutation in 4 patients with SLE and in an asymptomatic 9-year-old girl. Complement levels were low in sera from patients with truncated C1r protein. Two siblings with SLE who were available for detailed evaluation exhibited strong type I interferon (IFN) inflammatory signatures despite their disease being clinically inactive at the time of sampling. The type I IFN transcriptional signature in the patients' blood correlated with disease expressivity, whereas the neutrophil signature in peripheral blood mononuclear cells was likely associated with disease severity. The female patient with SLE with the most severe phenotype presented with a stronger neutrophil signature, defined by enhanced NET formation and the presence of low-density granulocytes. Analysis of exome data for modifying alleles suggested enrichment of common SLE-associated variants in the more severely affected patients. Lupus-associated HLA alleles or HLA haplotypes were not shared among the 4 affected subjects. CONCLUSION: Our findings revealed a novel high-penetrance mutation in C1R as the cause of monogenic SLE. Disease expressivity in this family appears to be influenced by additional common and rare genetic variants.
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Alelos , Complemento C1r/deficiencia , Predisposición Genética a la Enfermedad , Lupus Eritematoso Sistémico/genética , Adolescente , Adulto , Edad de Inicio , Niño , Preescolar , Complemento C1r/genética , Consanguinidad , Exoma , Femenino , Genotipo , Humanos , Interferón Tipo I/sangre , Leucocitos Mononucleares/citología , Lupus Eritematoso Sistémico/sangre , Masculino , Neutrófilos/metabolismo , Fenotipo , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN/métodos , Índice de Severidad de la Enfermedad , TurquíaRESUMEN
We analyzed 1,900 Turkish Behçet's disease cases and 1,779 controls genotyped with the Immunochip. The most significantly associated SNP was rs1050502, a tag SNP for HLA-B*51. In the Turkish discovery set, we identified three new risk loci, IL1A-IL1B, IRF8, and CEBPB-PTPN1, with genome-wide significance (P < 5 × 10-8) by direct genotyping and ADO-EGR2 by imputation. We replicated the ADO-EGR2, IRF8, and CEBPB-PTPN1 loci by genotyping 969 Iranian cases and 826 controls. Imputed data in 608 Japanese cases and 737 controls further replicated ADO-EGR2 and IRF8, and meta-analysis additionally identified RIPK2 and LACC1. The disease-associated allele of rs4402765, the lead marker at IL1A-IL1B, was associated with both decreased IL-1α and increased IL-1ß production. ABO non-secretor genotypes for two ancestry-specific FUT2 SNPs showed strong disease association (P = 5.89 × 10-15). Our findings extend the list of susceptibility genes shared with Crohn's disease and leprosy and implicate mucosal factors and the innate immune response to microbial exposure in Behçet's disease susceptibility.
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Síndrome de Behçet/genética , Sitios Genéticos/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Alelos , Estudios de Casos y Controles , Femenino , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Irán , Masculino , TurquíaRESUMEN
Approximately 71 million people are chronically infected with the hepatitis C virus (HCV), a potentially lethal pathogen. HCV generates oxidative stress correlating with disease severity. HCV proteins increase reactive oxygen species production by stimulating nicotinamide adenine dinucleotide phosphate oxidase (NOX) activity. Reactive oxygen species are necessary for host defense and cell signaling; however, elevated NOX activity contributes to cancer, and NOX overexpression is associated with hepatic fibrosis. Our aim was to investigate whether single nucleotide polymorphisms (SNPs) in NOX family members are associated with HCV-related liver damage. Three hundred and thirty-one individuals of European ancestry and 90 individuals of African ancestry, all diagnosed with HCV, were genotyped for 243 tagSNPs in NOX enzymes and their regulatory factors. Pathology scores were available for 288 Caucasians and 71 Africans, and mortality status was determined for all subjects. SNPs were tested for association with pathology scores and as predictors of mortality. In Africans, homozygosity for the A allele of rs12753665 (neutrophil cytosolic factor 2) and homozygosity for the T allele of rs760519 (neutrophil cytosolic factor 4) were associated with and predictive of higher rates of advanced fibrosis and cirrhosis compared to other genotypes after controlling for age and sex. In Caucasians, homozygosity for the T allele of rs2292464 (dual oxidase 1) was associated with and predictive of decreased periportal inflammation after controlling for age and sex. No SNPs were significant predictors of mortality. Conclusion: In this exploratory study, three NOX-related polymorphisms in two ethnic groups were significantly associated with hepatic inflammation and fibrosis. Future studies investigating these SNPs in larger cohorts of patients with HCV are warranted. (Hepatology Communications 2017;1:973-982).
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OBJECTIVES: Juvenile idiopathic arthritis (JIA) is a heterogeneous group of conditions unified by the presence of chronic childhood arthritis without an identifiable cause. Systemic JIA (sJIA) is a rare form of JIA characterised by systemic inflammation. sJIA is distinguished from other forms of JIA by unique clinical features and treatment responses that are similar to autoinflammatory diseases. However, approximately half of children with sJIA develop destructive, long-standing arthritis that appears similar to other forms of JIA. Using genomic approaches, we sought to gain novel insights into the pathophysiology of sJIA and its relationship with other forms of JIA. METHODS: We performed a genome-wide association study of 770 children with sJIA collected in nine countries by the International Childhood Arthritis Genetics Consortium. Single nucleotide polymorphisms were tested for association with sJIA. Weighted genetic risk scores were used to compare the genetic architecture of sJIA with other JIA subtypes. RESULTS: The major histocompatibility complex locus and a locus on chromosome 1 each showed association with sJIA exceeding the threshold for genome-wide significance, while 23 other novel loci were suggestive of association with sJIA. Using a combination of genetic and statistical approaches, we found no evidence of shared genetic architecture between sJIA and other common JIA subtypes. CONCLUSIONS: The lack of shared genetic risk factors between sJIA and other JIA subtypes supports the hypothesis that sJIA is a unique disease process and argues for a different classification framework. Research to improve sJIA therapy should target its unique genetics and specific pathophysiological pathways.
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Artritis Juvenil/genética , Cromosomas Humanos Par 1/genética , Complejo Mayor de Histocompatibilidad/genética , Artritis Juvenil/tratamiento farmacológico , Estudios de Casos y Controles , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Polimorfismo de Nucleótido Simple , Factores de RiesgoRESUMEN
Racial differences exist in the severity of systemic sclerosis (SSc). To enhance our knowledge about SSc in African Americans, we established a comprehensive clinical database from the largest multicenter cohort of African American SSc patients assembled to date (the Genome Research in African American Scleroderma Patients (GRASP) cohort).African American SSc patients were enrolled retrospectively and prospectively over a 30-year period (1987-2016), from 18 academic centers throughout the United States. The cross-sectional prevalence of sociodemographic, clinical, and serological features was evaluated. Factors associated with clinically significant manifestations of SSc were assessed using multivariate logistic regression analyses.The study population included a total of 1009 African American SSc patients, comprised of 84% women. In total, 945 (94%) patients met the 2013 American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) classification criteria for SSc, with the remaining 64 (6%) meeting the 1980 ACR or CREST (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasia) criteria. While 43% were actively employed, 33% required disability support. The majority (57%) had the more severe diffuse subtype and a young age at symptom onset (39.1â±â13.7 years), in marked contrast to that reported in cohorts of predominantly European ancestry. Also, 1 in 10 patients had a severe Medsger cardiac score of 4. Pulmonary fibrosis evident on computed tomography (CT) chest was present in 43% of patients and was significantly associated with anti-topoisomerase I positivity. 38% of patients with CT evidence of pulmonary fibrosis had a severe restrictive ventilator defect, forced vital capacity (FVC) ≤50% predicted. A significant association was noted between longer disease duration and higher odds of pulmonary hypertension, telangiectasia, and calcinosis. The prevalence of potentially fatal scleroderma renal crisis was 7%, 3.5 times higher than the 2% prevalence reported in the European League Against Rheumatism Scleroderma Trials and Research (EUSTAR) cohort.Our study emphasizes the unique and severe disease burden of SSc in African Americans compared to those of European ancestry.
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Esclerodermia Sistémica/epidemiología , Adulto , Negro o Afroamericano , Mapeo Cromosómico , Estudios de Cohortes , Estudios Transversales , Bases de Datos Factuales , Femenino , Humanos , Masculino , Prevalencia , Estudios Prospectivos , Estudios Retrospectivos , Esclerodermia Sistémica/sangre , Esclerodermia Sistémica/etnología , Esclerodermia Sistémica/fisiopatología , Índice de Severidad de la Enfermedad , Factores Socioeconómicos , Estados Unidos/epidemiologíaRESUMEN
Cell-to-cell expression variation (CEV) is a prevalent feature of even well-defined cell populations, but its functions, particularly at the organismal level, are not well understood. Using single-cell data obtained via high-dimensional flow cytometry of T cells as a model, we introduce an analysis framework for quantifying CEV in primary cell populations and studying its functional associations in human cohorts. Analyses of 840 CEV phenotypes spanning multiple baseline measurements of 14 proteins in 28 T cell subpopulations suggest that the quantitative extent of CEV can exhibit substantial subject-to-subject differences and yet remain stable within healthy individuals over months. We linked CEV to age and disease-associated genetic polymorphisms, thus implicating CEV as a biomarker of aging and disease susceptibility and suggesting that it might play an important role in health and disease. Our dataset, interactive figures, and software for computing CEV with flow cytometry data provide a resource for exploring CEV functions.
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Envejecimiento/inmunología , Linfocitos T/inmunología , Estudios de Cohortes , Femenino , Citometría de Flujo , Predisposición Genética a la Enfermedad , Humanos , Masculino , Fenotipo , Polimorfismo de Nucleótido SimpleRESUMEN
Systemic autoinflammatory diseases are caused by mutations in genes that function in innate immunity. Here, we report an autoinflammatory disease caused by loss-of-function mutations in OTULIN (FAM105B), encoding a deubiquitinase with linear linkage specificity. We identified two missense and one frameshift mutations in one Pakistani and two Turkish families with four affected patients. Patients presented with neonatal-onset fever, neutrophilic dermatitis/panniculitis, and failure to thrive, but without obvious primary immunodeficiency. HEK293 cells transfected with mutated OTULIN had decreased enzyme activity relative to cells transfected with WT OTULIN, and showed a substantial defect in the linear deubiquitination of target molecules. Stimulated patients' fibroblasts and peripheral blood mononuclear cells showed evidence for increased signaling in the canonical NF-κB pathway and accumulated linear ubiquitin aggregates. Levels of proinflammatory cytokines were significantly increased in the supernatants of stimulated primary cells and serum samples. This discovery adds to the emerging spectrum of human diseases caused by defects in the ubiquitin pathway and suggests a role for targeted cytokine therapies.
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Alelos , Endopeptidasas/genética , Fibroblastos/patología , Enfermedades Autoinflamatorias Hereditarias/genética , Leucocitos Mononucleares/patología , Mutación , Edad de Inicio , Niño , Preescolar , Consanguinidad , Citocinas/genética , Citocinas/inmunología , Dermatitis/fisiopatología , Endopeptidasas/deficiencia , Endopeptidasas/inmunología , Insuficiencia de Crecimiento/fisiopatología , Femenino , Fiebre/fisiopatología , Fibroblastos/enzimología , Fibroblastos/inmunología , Regulación de la Expresión Génica , Células HEK293 , Enfermedades Autoinflamatorias Hereditarias/diagnóstico , Enfermedades Autoinflamatorias Hereditarias/enzimología , Enfermedades Autoinflamatorias Hereditarias/patología , Humanos , Leucocitos Mononucleares/enzimología , Leucocitos Mononucleares/inmunología , Masculino , FN-kappa B/genética , FN-kappa B/inmunología , Paniculitis/fisiopatología , Linaje , Transducción de Señal , Ubiquitina/genética , Ubiquitina/inmunologíaRESUMEN
BACKGROUND: Case reports have linked adult hypophosphatasia as a possible cause of atypical femur fractures (AFF) associated with bisphosphonate use. Adult hypophosphatasia is an asymptomatic genetic condition which results in low alkaline phosphatase and elevated pyridoxal phosphate. We conducted a case-control study to assess the role of hypophosphatasia and atypical femur fracture. METHODS: We recruited 13 control patients who took long term bisphosphonates without complication and 10 patients who sustained atypical femur fractures (mean bisphosphonate use, 9 years both cohorts). Patients underwent clinical exam and measurement of alkaline phosphatase and pyridoxal phosphate (PLP) levels. In addition, DNA was extracted and the ALPL gene was sequenced in both cohorts. RESULTS: Low alkaline phosphatase levels (<55 U/L) were seen in 5/10 AFF patients and 5/13 control patients. Two control patients demonstrated low alkaline phosphatase levels and elevated PLP. The alkaline phosphatase (ALPL) gene exons and intron splice sites were sequenced in the atypical femur fracture and control cohorts and no coding mutations were identified in any subjects. Atypical femur fracture patients demonstrated more varus hip alignment (p < 0.048) with no significant difference in mechanical axis. CONCLUSIONS: We found no evidence of hypophosphatasia as a risk factor for atypical femur fractures. Laboratory findings of mildly low alkaline phosphatase activity were equally common in atypical and control cohorts and may be due to long term bisphosphonate use. TRIAL REGISTRATION: Clinicaltrials.gov number NCT01360099 . Prospectively registered May 20, 2011. First patient enrolled June 14, 2011.