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1.
Nat Commun ; 11(1): 5341, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087723

RESUMO

Autoimmunity can occur when a checkpoint of self-tolerance fails. The study of familial autoimmune diseases can reveal pathophysiological mechanisms involved in more common autoimmune diseases. Here, by whole-exome/genome sequencing we identify heterozygous, autosomal-dominant, germline loss-of-function mutations in the SOCS1 gene in ten patients from five unrelated families with early onset autoimmune manifestations. The intracellular protein SOCS1 is known to downregulate cytokine signaling by inhibiting the JAK-STAT pathway. Accordingly, patient-derived lymphocytes exhibit increased STAT activation in vitro in response to interferon-γ, IL-2 and IL-4 that is reverted by the JAK1/JAK2 inhibitor ruxolitinib. This effect is associated with a series of in vitro and in vivo immune abnormalities consistent with lymphocyte hyperactivity. Hence, SOCS1 haploinsufficiency causes a dominantly inherited predisposition to early onset autoimmune diseases related to cytokine hypersensitivity of immune cells.


Assuntos
Doenças Autoimunes/genética , Doenças Autoimunes/imunologia , Autoimunidade/genética , Proteína 1 Supressora da Sinalização de Citocina/deficiência , Proteína 1 Supressora da Sinalização de Citocina/genética , Adolescente , Adulto , Idade de Início , Doenças Autoimunes/metabolismo , Criança , Pré-Escolar , Citocinas/metabolismo , Feminino , Haploinsuficiência , Humanos , Masculino , Modelos Moleculares , Mutação , Linhagem , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Proteína 1 Supressora da Sinalização de Citocina/química , Linfócitos T/imunologia
2.
Nat Commun ; 11(1): 4859, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978401

RESUMO

Cell death is intrinsically linked with immunity. Disruption of an immune-activated MAPK cascade, consisting of MEKK1, MKK1/2, and MPK4, triggers cell death and autoimmunity through the nucleotide-binding leucine-rich repeat (NLR) protein SUMM2 and the MAPK kinase kinase MEKK2. In this study, we identify a Catharanthus roseus receptor-like kinase 1-like (CrRLK1L), named LETUM2/MEDOS1 (LET2/MDS1), and the glycosylphosphatidylinositol (GPI)-anchored protein LLG1 as regulators of mekk1-mkk1/2-mpk4 cell death. LET2/MDS1 functions additively with LET1, another CrRLK1L, and acts genetically downstream of MEKK2 in regulating SUMM2 activation. LET2/MDS1 complexes with LET1 and promotes LET1 phosphorylation, revealing an intertwined regulation between different CrRLK1Ls. LLG1 interacts with the ectodomain of LET1/2 and mediates LET1/2 transport to the plasma membrane, corroborating its function as a co-receptor of LET1/2 in the mekk1-mkk1/2-mpk4 cell death pathway. Thus, our data suggest that a trimeric complex consisting of two CrRLK1Ls LET1, LET2/MDS1, and a GPI-anchored protein LLG1 that regulates the activation of NLR SUMM2 for initiating cell death and autoimmunity.


Assuntos
Autoimunidade/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas Ligadas por GPI/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Autoimunidade/fisiologia , Proteínas de Transporte/imunologia , Catharanthus/genética , Catharanthus/metabolismo , Morte Celular/genética , Proteínas Ligadas por GPI/genética , Regulação da Expressão Gênica de Plantas , Glicosilfosfatidilinositóis , MAP Quinase Quinase Quinases/genética , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fosforilação , Proteínas de Plantas/imunologia , Plantas Geneticamente Modificadas , Interferência de RNA , Transcriptoma
3.
Clin Immunol ; 220: 108591, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32920210

RESUMO

Most severe cases with COVID-19, especially those with pulmonary failure, are not a consequence of viral burden and/or failure of the 'adaptive' immune response to subdue the pathogen by utilizing an adequate 'adaptive' immune defense. Rather it is a consequence of immunopathology, resulting from imbalanced innate immune response, which may not be linked to pathogen burden at all. In fact, it might be described as an autoinflammatory disease. The Kawasaki-like disease seen in children with SARS-CoV-2 exposure might be another example of similar mechanism.


Assuntos
Autoimunidade/genética , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Interações Hospedeiro-Patógeno/imunologia , Pneumonia Viral/imunologia , Insuficiência Respiratória/imunologia , Doença Aguda , Imunidade Adaptativa , Betacoronavirus/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/patologia , Linfócitos T CD8-Positivos/virologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/fisiopatologia , Síndrome da Liberação de Citocina/genética , Síndrome da Liberação de Citocina/fisiopatologia , Interações Hospedeiro-Patógeno/genética , Humanos , Imunidade Inata , Ativação Linfocitária , Síndrome de Linfonodos Mucocutâneos/genética , Síndrome de Linfonodos Mucocutâneos/imunologia , Síndrome de Linfonodos Mucocutâneos/fisiopatologia , Pandemias , Pneumonia Viral/genética , Pneumonia Viral/fisiopatologia , Insuficiência Respiratória/genética , Insuficiência Respiratória/fisiopatologia , Índice de Gravidade de Doença
4.
Nat Med ; 26(8): 1247-1255, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32770166

RESUMO

Type 1 diabetes (T1D)-an autoimmune disease that destroys the pancreatic islets, resulting in insulin deficiency-often begins early in life when islet autoantibody appearance signals high risk1. However, clinical diabetes can follow in weeks or only after decades, and is very difficult to predict. Ketoacidosis at onset remains common2,3 and is most severe in the very young4,5, in whom it can be life threatening and difficult to treat6-9. Autoantibody surveillance programs effectively prevent most ketoacidosis10-12 but require frequent evaluations whose expense limits public health adoption13. Prevention therapies applied before onset, when greater islet mass remains, have rarely been feasible14 because individuals at greatest risk of impending T1D are difficult to identify. To remedy this, we sought accurate, cost-effective estimation of future T1D risk by developing a combined risk score incorporating both fixed and variable factors (genetic, clinical and immunological) in 7,798 high-risk children followed closely from birth for 9.3 years. Compared with autoantibodies alone, the combined model dramatically improves T1D prediction at ≥2 years of age over horizons up to 8 years of age (area under the receiver operating characteristic curve ≥ 0.9), doubles the estimated efficiency of population-based newborn screening to prevent ketoacidosis, and enables individualized risk estimates for better prevention trial selection.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Cetose/sangue , Medição de Risco , Autoanticorpos/imunologia , Autoimunidade/genética , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/imunologia , Feminino , Predisposição Genética para Doença , Humanos , Lactente , Recém-Nascido , Insulina/deficiência , Insulina/imunologia , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/patologia , Cetose/imunologia , Masculino , Triagem Neonatal , Fatores de Risco
5.
Eur J Endocrinol ; 183(1): 73-81, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32487775

RESUMO

Objective: Autoimmune conditions tend to cluster in subjects with Addison's disease (AD) and probably also among their relatives. The aim of the study was to estimate the frequency of the endocrine gland-specific autoantibodies in first-degree relatives of patients with AD. Methods: Autoantibodies were investigated in 113 family members using RIA and ELISA assays. The control group comprised 143 age-matched volunteers. Results: Autoimmune diseases were diagnosed in 38.1% relatives. Hashimoto's thyroiditis was found in 20.3%, Graves' disease in 8.0%, vitiligo and type 1 diabetes in 3.5%, whereas AD, rheumatoid arthritis and atrophic gastritis with pernicious anaemia in 2.7% each. All studied antibodies except for islet antigen-2 (P = 0.085) were significantly more frequent in AD relatives than in controls (P < 0.05). Antibodies to 21-hydroxylase were detected in 6.2% relatives, thyroid peroxidase in 28.3%, thyroglobulin in 19.5%, glutamic acid decarboxylase in 8.0%, and zinc transporter-8 in 7.1%. Two and more autoantibodies were detected in 18.6% subjects. Significant gender difference was revealed only for aTPO, more common in female relatives (P = 0.014; OR: 3.16; 95% CI: 1.23-8.12). Circulating autoantibodies were found more frequently in the relatives of affected males (P = 0.008; OR: 3.31; 95% CI: 1.33-8.23), and in family members of patients with polyendocrine autoimmunity (P = 0.009; OR: 3.55; 95% CI: 1.31-9.57). Conclusions: This study provides evidence of increased susceptibility for the endocrine autoimmunity, especially thyroid disease, in close relatives of patients with AD. Relatives of the male AD patients and of those with autoimmune polyendocrine syndrome are at particular risk and should undergo periodic screening for autoimmune endocrine disorders.


Assuntos
Doença de Addison/genética , Doença de Addison/imunologia , Autoimunidade/genética , Glândulas Endócrinas/imunologia , Doença de Addison/sangue , Adulto , Autoanticorpos/sangue , Estudos Transversais , Família , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
6.
Ann Rheum Dis ; 79(9): 1218-1226, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32561607

RESUMO

OBJECTIVES: The analysis of annotated transcripts from genome-wide expression studies may help to understand the pathogenesis of complex diseases, such as systemic sclerosis (SSc). We performed a whole blood (WB) transcriptome analysis on RNA collected in the context of the European PRECISESADS project, aiming at characterising the pathways that differentiate SSc from controls and that are reproducible in geographically diverse populations. METHODS: Samples from 162 patients and 252 controls were collected in RNA stabilisers. Cases and controls were divided into a discovery (n=79+163; Southern Europe) and validation cohort (n=83+89; Central-Western Europe). RNA sequencing was performed by an Illumina assay. Functional annotations of Reactome pathways were performed with the Functional Analysis of Individual Microarray Expression (FAIME) algorithm. In parallel, immunophenotyping of 28 circulating cell populations was performed. We tested the presence of differentially expressed genes/pathways and the correlation between absolute cell counts and RNA transcripts/FAIME scores in regression models. Results significant in both populations were considered as replicated. RESULTS: Overall, 15 224 genes and 1277 functional pathways were available; of these, 99 and 225 were significant in both sets. Among replicated pathways, we found a deregulation in type-I interferon, Toll-like receptor cascade, tumour suppressor p53 protein function, platelet degranulation and activation. RNA transcripts or FAIME scores were jointly correlated with cell subtypes with strong geographical differences; neutrophils were the major determinant of gene expression in SSc-WB samples. CONCLUSIONS: We discovered a set of differentially expressed genes/pathways validated in two independent sets of patients with SSc, highlighting a number of deregulated processes that have relevance for the pathogenesis of autoimmunity and SSc.


Assuntos
Autoimunidade/genética , Escleroderma Sistêmico/genética , Transdução de Sinais/genética , Transcriptoma/genética , Adulto , Idoso , Estudos de Coortes , Europa (Continente) , Feminino , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Imunofenotipagem , Interferon Tipo I/sangue , Masculino , Análise em Microsséries , Pessoa de Meia-Idade , Análise de Sequência de RNA , Receptores Toll-Like/sangue
7.
Nature ; 582(7810): 89-94, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32483373

RESUMO

A hexanucleotide-repeat expansion in C9ORF72 is the most common genetic variant that contributes to amyotrophic lateral sclerosis and frontotemporal dementia1,2. The C9ORF72 mutation acts through gain- and loss-of-function mechanisms to induce pathways that are implicated in neural degeneration3-9. The expansion is transcribed into a long repetitive RNA, which negatively sequesters RNA-binding proteins5 before its non-canonical translation into neural-toxic dipeptide proteins3,4. The failure of RNA polymerase to read through the mutation also reduces the abundance of the endogenous C9ORF72 gene product, which functions in endolysosomal pathways and suppresses systemic and neural inflammation6-9. Notably, the effects of the repeat expansion act with incomplete penetrance in families with a high prevalence of amyotrophic lateral sclerosis or frontotemporal dementia, indicating that either genetic or environmental factors modify the risk of disease for each individual. Identifying disease modifiers is of considerable translational interest, as it could suggest strategies to diminish the risk of developing amyotrophic lateral sclerosis or frontotemporal dementia, or to slow progression. Here we report that an environment with reduced abundance of immune-stimulating bacteria10,11 protects C9orf72-mutant mice from premature mortality and significantly ameliorates their underlying systemic inflammation and autoimmunity. Consistent with C9orf72 functioning to prevent microbiota from inducing a pathological inflammatory response, we found that reducing the microbial burden in mutant mice with broad spectrum antibiotics-as well as transplanting gut microflora from a protective environment-attenuated inflammatory phenotypes, even after their onset. Our studies provide further evidence that the microbial composition of our gut has an important role in brain health and can interact in surprising ways with well-known genetic risk factors for disorders of the nervous system.


Assuntos
Proteína C9orf72/genética , Microbioma Gastrointestinal/fisiologia , Gliose/microbiologia , Gliose/patologia , Inflamação/genética , Inflamação/microbiologia , Medula Espinal/patologia , Esclerose Amiotrófica Lateral/genética , Esclerose Amiotrófica Lateral/patologia , Animais , Antibacterianos/farmacologia , Autoimunidade/efeitos dos fármacos , Autoimunidade/genética , Autoimunidade/imunologia , Movimento Celular/efeitos dos fármacos , Citocinas/imunologia , Transplante de Microbiota Fecal , Feminino , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Gliose/genética , Gliose/prevenção & controle , Inflamação/patologia , Inflamação/prevenção & controle , Mutação com Perda de Função/genética , Masculino , Camundongos , Microglia/imunologia , Microglia/microbiologia , Microglia/patologia , Medula Espinal/imunologia , Medula Espinal/microbiologia , Taxa de Sobrevida
8.
PLoS Genet ; 16(6): e1008861, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32525870

RESUMO

In metazoan germlines, the piRNA pathway acts as a genomic immune system, employing small RNA-mediated silencing to defend host DNA from the harmful effects of transposable elements (TEs). Expression of genomic TEs is proposed to initiate self regulation by increasing the production of repressive piRNAs, thereby "adapting" piRNA-mediated control to the most active TE families. Surprisingly, however, piRNA pathway proteins, which execute piRNA biogenesis and enforce silencing of targeted sequences, evolve rapidly and adaptively in animals. If TE silencing is ensured through piRNA biogenesis, what necessitates changes in piRNA pathway proteins? Here we used interspecific complementation to test for functional differences between Drosophila melanogaster and D. simulans alleles of three adaptively evolving piRNA pathway proteins: Armitage, Aubergine and Spindle-E. In contrast to piRNA-mediated transcriptional regulators examined in previous studies, these three proteins have cytoplasmic functions in piRNA maturation and post-transcriptional silencing. Across all three proteins we observed interspecific divergence in the regulation of only a handful of TE families, which were more robustly silenced by the heterospecific piRNA pathway protein. This unexpected result suggests that unlike transcriptional regulators, positive selection has not acted on cytoplasmic piRNA effector proteins to enhance their function in TE repression. Rather, TEs may evolve to "escape" silencing by host proteins. We further discovered that D. simulans alleles of aub and armi exhibit enhanced off-target effects on host transcripts in a D. melanogaster background, as well as modest reductions in the efficiency of piRNA biogenesis, suggesting that promiscuous binding of D. simulans Aub and Armi proteins to host transcripts reduces their participation in piRNA production. Avoidance of genomic auto-immunity may therefore be a critical target of selection. Our observations suggest that piRNA effector proteins are subject to an evolutionary trade-off between defending the host genome from the harmful effect of TEs while also minimizing collateral damage to host genes.


Assuntos
Autoimunidade/genética , Elementos de DNA Transponíveis/imunologia , Drosophila simulans/genética , Evolução Molecular , Genoma de Inseto/imunologia , RNA Interferente Pequeno/biossíntese , Alelos , Animais , Animais Geneticamente Modificados , Citoplasma/genética , Citoplasma/metabolismo , Elementos de DNA Transponíveis/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/imunologia , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/imunologia , Drosophila melanogaster/metabolismo , Drosophila simulans/metabolismo , Feminino , Regulação da Expressão Gênica/imunologia , Genoma de Inseto/genética , Masculino , Mutação , Interferência de RNA/imunologia
9.
Best Pract Res Clin Endocrinol Metab ; 34(1): 101412, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32265102

RESUMO

An adjuvant is an immunological or pharmacological substance or group of substances that can be added to a given agent to enhance its effect in terms of efficacy, effectiveness and potency. Different mechanisms have been hypothesized underlying the action of the adjuvant, including boosting immune (innate and adaptive) response: this generally results in sparing the necessary amount of the agent and can potentially reduce the frequency of the needed number of therapeutic interventions. Adjuvants can be commonly found in vaccines, immunization products, mineral oils, cosmetics, silicone breast implants and other therapeutic/medical devices, being usually safe and effective. However, in a fraction of genetically susceptible and predisposed subjects, the administration of adjuvants may lead to the insurgence of serious side-effects, called "autoimmune/inflammatory syndrome by adjuvants" (ASIA) or Shoenfeld's syndrome. The present review is aimed at focusing on the "endocrine pebbles" of the mosaic of autoimmunity and of the ASIA syndrome, collecting together 54 cases of sub-acute thyroiditis, 2 cases of Hashimoto's thyroiditis, 11 cases of primary ovarian failure/primary ovarian insufficiency, 13 cases of autoimmune diabetes type 1, and 1 case of autoimmune adrenal gland insufficiency occurred after exposure to adjuvants.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Doenças Autoimunes/induzido quimicamente , Autoimunidade/efeitos dos fármacos , Doenças do Sistema Endócrino/induzido quimicamente , Doenças Autoimunes/genética , Autoimunidade/genética , Diabetes Mellitus Tipo 1/induzido quimicamente , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/imunologia , Doenças do Sistema Endócrino/genética , Doenças do Sistema Endócrino/imunologia , Predisposição Genética para Doença , Humanos , Fatores de Risco , Síndrome
10.
Eur J Endocrinol ; 182(5): 473-480, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32229696

RESUMO

Objective: Co-aggregation of autoimmune diseases is common, suggesting partly shared etiologies. Genetic factors are believed to be important, but objective measures of environmental vs heritable influences on co-aggregation are absent. With a novel approach to twin studies, we aimed at estimating heritability and genetic overlap in seven organ-specific autoimmune diseases. Design: Prospective twin cohort study. Methods: We used a cohort of 110 814 twins to examine co-aggregation and heritability of Hashimoto's thyroiditis, atrophic gastritis, celiac disease, Graves' disease, type 1 diabetes, vitiligo and Addison's disease. Hazard ratios (HR) were calculated for twins developing the same or different disease as compared to their co-twin. The differences between monozygotic and dizygotic twin pairs were used to estimate the genetic influence on co-aggregation. Heritability for individual disorders was calculated using structural equational modeling adjusting for censoring and truncation of data. Results: Co-aggregation was more pronounced in monozygotic twins (median HR: 3.2, range: 2.2-9.2) than in dizygotic twins (median HR: 2.4, range: 1.1-10.0). Heritability was moderate for atrophic gastritis (0.38, 95% CI: 0.23-0.53) but high for all other diseases, ranging from 0.60 (95% CI: 0.49-0.71) for Graves' disease to 0.97 (95% CI: 0.91-1.00) for Addison's disease. Conclusions: Overall, co-aggregation was more pronounced in monozygotic than in dizygotic twins, suggesting that disease overlap is largely attributable to genetic factors. Co-aggregation was common, and twins faced up to a ten-fold risk of developing diseases not present in their co-twin. Our results validate and refine previous heritability estimates based on smaller twin cohorts.


Assuntos
Autoimunidade/fisiologia , Doença de Addison/genética , Autoimunidade/genética , Doença Celíaca/genética , Estudos de Coortes , Feminino , Gastrite Atrófica/genética , Predisposição Genética para Doença/genética , Doença de Graves/genética , Humanos , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética
12.
Mol Immunol ; 121: 28-37, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32151906

RESUMO

INTRODUCTION: H Syndrome is an autosomal recessive (AR) disease caused by defects in SLCA29A3 gene. This gene encodes the equilibrative nucleoside transporter, the protein which is highly expressed in spleen, lymph node and bone marrow. Autoinflammation and autoimmunity accompanies H Syndrome (HS). AIM: The aim was to further elucidate the mechanisms of disease by molecular studies in a patient with SLC29A3 gene defect. PATIENT AND METHODS: Mitochondrial dysfunction, lysosomal integrity, cytokine response in response to stimulation with different pattern recognition receptor ligands, and circulating cell-free mitochondrial-DNA(ccf-mtDNA) level in plasma were analyzed compared to controls to understand the cellular triggers of autoinflammation. RNA sequencing (RS) analyses were also performed in monocytes before/after culture with lipopolysaccharide. RESULTS: Patient had progressive destructive arthropathy in addition to clinical findings due to combined immunodeficiency. Pure red cell aplasia (PRCA), vitiligo, diabetes, multiple autoantibody positivity, lymphopenia, increased acute phase reactants were present. Recent thymic emigrants (RTE), naïve T cells were decreased, effector memory CD4 + T cells, nonclassical inflammatory monocytes were increased. Patient's peripheral blood mononuclear cells secreted more IL-1ß and IL-6, showed lysosomal disruption and significant mitochondrial dysfunction compared to healthy controls. Plasma ccf-mtDNA level was significantly elevated compared to age-matched controls (p < 0.05). RNA sequencing studies revealed decreased expression of NLR Family Caspase Recrument-Domain Containing 4(NLRC4), 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 4(PFKFB4), serine dehydratase(SDS), heparan sulfate(Glucosamine) 3-O-sulfotransferase 1(HS3ST1), neutral cholesterol ester hydrolase 1 (NCEH1), and interleukin-8 (IL-8) in patient's monocytes compared to controls. Longstanding PRCA, which is possibly autoimmune, resolved after initiating monthly intravenous immunoglobulins (IVIG) and low dose steroids to the patient. CONCLUSION: Although autoinflammation and autoimmunity are reported in HS, by functional analyses we here show in the present patient that over-active inflammasome pathway in HS might be related with mitochondrial and lysosomal dysfunction. Increased plasma ccf-mtDNA may be used as a biomarker of inflammasomopathy in HS. HS should be included in the classification of primary immunodeficiency diseases.


Assuntos
Autoimunidade/genética , Contratura/genética , Perda Auditiva Neurossensorial/genética , Histiocitose/genética , Síndromes de Imunodeficiência/genética , Proteínas de Transporte de Nucleosídeos/genética , Adolescente , Contratura/tratamento farmacológico , Contratura/imunologia , Contratura/patologia , Glucocorticoides/uso terapêutico , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/imunologia , Perda Auditiva Neurossensorial/patologia , Histiocitose/tratamento farmacológico , Histiocitose/imunologia , Histiocitose/patologia , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Síndromes de Imunodeficiência/tratamento farmacológico , Síndromes de Imunodeficiência/imunologia , Síndromes de Imunodeficiência/patologia , Inflamassomos/imunologia , Lisossomos/imunologia , Lisossomos/patologia , Masculino , Mitocôndrias/imunologia , Mitocôndrias/patologia , Resultado do Tratamento
14.
Nat Genet ; 52(3): 247-253, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32066938

RESUMO

Genetic studies have revealed that autoimmune susceptibility variants are over-represented in memory CD4+ T cell regulatory elements1-3. Understanding how genetic variation affects gene expression in different T cell physiological states is essential for deciphering genetic mechanisms of autoimmunity4,5. Here, we characterized the dynamics of genetic regulatory effects at eight time points during memory CD4+ T cell activation with high-depth RNA-seq in healthy individuals. We discovered widespread, dynamic allele-specific expression across the genome, where the balance of alleles changes over time. These genes were enriched fourfold within autoimmune loci. We found pervasive dynamic regulatory effects within six HLA genes. HLA-DQB1 alleles had one of three distinct transcriptional regulatory programs. Using CRISPR-Cas9 genomic editing we demonstrated that a promoter variant is causal for T cell-specific control of HLA-DQB1 expression. Our study shows that genetic variation in cis-regulatory elements affects gene expression in a manner dependent on lymphocyte activation status, contributing to the interindividual complexity of immune responses.


Assuntos
Autoimunidade/genética , Variação Genética , Antígenos HLA/genética , Cadeias beta de HLA-DQ/genética , Ativação Linfocitária/genética , Regiões Promotoras Genéticas/genética , Alelos , Linfócitos T CD4-Positivos , Sistemas CRISPR-Cas , Linhagem Celular , Regulação da Expressão Gênica , Loci Gênicos , Técnicas de Genotipagem , Antígenos HLA/metabolismo , Cadeias beta de HLA-DQ/metabolismo , Humanos , Imunidade Celular , Linfócitos T Reguladores
15.
PLoS Biol ; 18(2): e3000590, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32069316

RESUMO

DO (HLA-DO, in human; murine H2-O) is a highly conserved nonclassical major histocompatibility complex class II (MHC II) accessory molecule mainly expressed in the thymic medulla and B cells. Previous reports have suggested possible links between DO and autoimmunity, Hepatitis C (HCV) infection, and cancer, but the mechanism of how DO contributes to these diseases remains unclear. Here, using a combination of various in vivo approaches, including peptide elution, mixed lymphocyte reaction, T-cell receptor (TCR) deep sequencing, tetramer-guided naïve CD4 T-cell precursor enumeration, and whole-body imaging, we report that DO affects the repertoire of presented self-peptides by B cells and thymic epithelium. DO induces differential effects on epitope presentation and thymic selection, thereby altering CD4 T-cell precursor frequencies. Our findings were validated in two autoimmune disease models by demonstrating that lack of DO increases autoreactivity and susceptibility to autoimmune disease development.


Assuntos
Doenças Autoimunes/genética , Predisposição Genética para Doença/genética , Antígenos de Histocompatibilidade Classe II/genética , Animais , Células Apresentadoras de Antígenos/imunologia , Doenças Autoimunes/imunologia , Autoimunidade/genética , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Colágeno/administração & dosagem , Colágeno/imunologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Glicoproteína Mielina-Oligodendrócito/imunologia , Peptídeos/imunologia , Células Precursoras de Linfócitos T/imunologia , Timo/imunologia
16.
Immunity ; 52(2): 342-356.e6, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32023490

RESUMO

Interleukin-17A (IL-17A) is a major mediator of tissue inflammation in many autoimmune diseases. Anti-IL-17A is an effective treatment for psoriasis and is showing promise in clinical trials in multiple sclerosis. In this study, we find that IL-17A-defective mice or mice treated with anti-IL-17A at induction of experimental autoimmune encephalomyelitis (EAE) are resistant to disease and have defective priming of IL-17-secreting γδ T (γδT17) cells and Th17 cells. However, T cells from Il17a-/- mice induce EAE in wild-type mice following in vitro culture with autoantigen, IL-1ß, and IL-23. Furthermore, treatment with IL-1ß or IL-17A at induction of EAE restores disease in Il17a-/- mice. Importantly, mobilization of IL-1ß-producing neutrophils and inflammatory monocytes and activation of γδT17 cells is reduced in Il17a-/- mice. Our findings demonstrate that a key function of IL-17A in central nervous system (CNS) autoimmunity is to recruit IL-1ß-secreting myeloid cells that prime pathogenic γδT17 and Th17 cells.


Assuntos
Autoimunidade/imunologia , Interleucina-17/imunologia , Interleucina-1beta/metabolismo , Linfócitos Intraepiteliais/imunologia , Células Mieloides/imunologia , Células Th17/imunologia , Animais , Autoantígenos/imunologia , Autoimunidade/genética , Sistema Nervoso Central/imunologia , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Interleucina-17/antagonistas & inibidores , Interleucina-17/deficiência , Interleucina-17/metabolismo , Interleucina-1beta/imunologia , Interleucina-23/imunologia , Interleucina-23/metabolismo , Linfócitos Intraepiteliais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Monócitos/metabolismo , Células Mieloides/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Células Th17/metabolismo
17.
J Leukoc Biol ; 107(6): 893-905, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32083339

RESUMO

TNF is a key proinflammatory and immunoregulatory cytokine whose deregulation is associated with the development of autoimmune diseases and other pathologies. Recent studies suggest that distinct functions of TNF may be associated with differential engagement of its two receptors: TNFR1 or TNFR2. In this review, we discuss the relative contributions of these receptors to pathogenesis of several diseases, with the focus on autoimmunity and neuroinflammation. In particular, we discuss the role of TNFRs in the development of regulatory T cells during neuroinflammation and recent findings concerning targeting TNFR2 with agonistic and antagonistic reagents in various murine models of autoimmune and neuroinflammatory disorders and cancer.


Assuntos
Encefalomielite Autoimune Experimental/genética , Esclerose Múltipla/genética , Neuroimunomodulação/genética , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/genética , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Autoimunidade/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Regulação da Expressão Gênica , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Camundongos , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Neoplasias/genética , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Psoríase/genética , Psoríase/imunologia , Psoríase/metabolismo , Psoríase/patologia , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/imunologia , Transdução de Sinais/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Fator de Necrose Tumoral alfa/imunologia
18.
Blood ; 135(9): 610-619, 2020 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-31942628

RESUMO

Traditionally, primary immune deficiencies have been defined based on increased susceptibility to recurrent and/or severe infections. However, immune dysregulation, manifesting with autoimmunity or hyperinflammatory disease, has emerged as a common feature. This is especially true in patients affected by combined immune deficiency (CID), a group of disorders caused by genetic defects that impair, but do not completely abolish, T-cell function. Hypomorphic mutations in the recombination activating genes RAG1 and RAG2 represent the prototype of the broad spectrum of clinical and immunological phenotypes associated with CID. The study of patients with RAG deficiency and with other forms of CID has revealed distinct abnormalities in central and peripheral T- and B-cell tolerance as the key mechanisms involved in immune dysregulation. Understanding the pathophysiology of autoimmunity and hyperinflammation in these disorders may also permit more targeted therapeutic interventions.


Assuntos
Imunodeficiência Combinada Severa/imunologia , Autoimunidade/genética , Autoimunidade/imunologia , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/imunologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/imunologia , Humanos , Proteínas Nucleares/deficiência , Proteínas Nucleares/imunologia , Imunodeficiência Combinada Severa/genética
19.
Annu Rev Pathol ; 15: 51-70, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31977294

RESUMO

Our genome is a historic record of successive invasions of mobile genetic elements. Like other eukaryotes, we have evolved mechanisms to limit their propagation and minimize the functional impact of new insertions. Although these mechanisms are vitally important, they are imperfect, and a handful of retroelement families remain active in modern humans. This review introduces the intrinsic functions of transposons, the tactics employed in their restraint, and the relevance of this conflict to human pathology. The most straightforward examples of disease-causing transposable elements are germline insertions that disrupt a gene and result in a monogenic disease allele. More enigmatic are the abnormal patterns of transposable element expression in disease states. Changes in transposon regulation and cellular responses to their expression have implicated these sequences in diseases as diverse as cancer, autoimmunity, and neurodegeneration. Distinguishing their epiphenomenal from their pathogenic effects may provide wholly new perspectives on our understanding of disease.


Assuntos
Elementos de DNA Transponíveis/fisiologia , Doença/genética , Alelos , Animais , Autoimunidade/genética , Genoma Humano/fisiologia , Mutação em Linhagem Germinativa/fisiologia , Humanos , Mutagênese Insercional/fisiologia , Neoplasias/genética , Neoplasias/patologia , Degeneração Neural/genética , Degeneração Neural/patologia , Retroelementos/fisiologia
20.
J Exp Med ; 217(2)2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31841125

RESUMO

Antibody-mediated autoimmune diseases are a major health burden. However, our understanding of how self-reactive B cells escape self-tolerance checkpoints to secrete pathogenic autoantibodies remains incomplete. Here, we demonstrate that patients with monogenic immune dysregulation caused by gain-of-function mutations in PIK3CD, encoding the p110δ catalytic subunit of phosphoinositide 3-kinase (PI3K), have highly penetrant secretion of autoreactive IgM antibodies. In mice with the corresponding heterozygous Pik3cd activating mutation, self-reactive B cells exhibit a cell-autonomous subversion of their response to self-antigen: instead of becoming tolerized and repressed from secreting autoantibody, Pik3cd gain-of-function B cells are activated by self-antigen to form plasmablasts that secrete high titers of germline-encoded IgM autoantibody and hypermutating germinal center B cells. However, within the germinal center, peripheral tolerance was still enforced, and there was selection against B cells with high affinity for self-antigen. These data show that the strength of PI3K signaling is a key regulator of pregerminal center B cell self-tolerance and thus represents a druggable pathway to treat antibody-mediated autoimmunity.


Assuntos
Formação de Anticorpos/genética , Autoanticorpos/imunologia , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação com Ganho de Função , Tolerância Imunológica/imunologia , Plasmócitos/imunologia , Animais , Autoanticorpos/sangue , Autoantígenos/imunologia , Autoimunidade/genética , Classe I de Fosfatidilinositol 3-Quinases/sangue , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Feminino , Centro Germinativo/imunologia , Humanos , Imunoglobulina M/sangue , Imunoglobulina M/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Transdução de Sinais/genética
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