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2.
Croat Med J ; 61(3): 230-238, 2020 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-32643339

RESUMO

AIM: To analyze the association of thyroid function and hormone levels with metabolic syndrome (MetS) and its components. METHODS: This cross-sectional population-based study involved 2183 Croatian individuals with no history of thyroid disease, hypertension, diabetes, and hyperlipidemia. MetS was diagnosed according to the National Cholesterol Education Program's Adult Treatment Panel III criteria. RESULTS: We found no association between thyroid function groups and the prevalence of MetS and its components. Clinically hypothyroid participants showed significantly higher triceps skinfold measurements than subclinically hypothyroid and euthyroid participants. Furthermore, clinically hypothyroid participants had higher abdominal skinfold thickness than subclinically hypothyroid participants. Otherwise, suprailiac and abdominal skinfold measurements were higher in the subclinically and clinically hyperthyroid group of participants compared with euthyroid and subclinically hypothyroid participants. A strong positive association of thyroid-stimulating hormone (TSH) and strong negative association of free triiodothyronine (fT3) and free thyroxine (fT4) levels with HOMA-IR and cholesterol levels were found. Furthermore, the fT4 level also showed a strong negative association with HDL and triceps skinfold thickness. CONCLUSIONS: This study supports the standing that TSH, fT3, and fT4 levels are important variables to determine the association of thyroid function with MetS.


Assuntos
Síndrome Metabólica/sangue , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Autoanticorpos/sangue , Autoantígenos/imunologia , Colesterol/sangue , Estudos Transversais , Feminino , Humanos , Iodeto Peroxidase/imunologia , Proteínas de Ligação ao Ferro/imunologia , Medições Luminescentes , Masculino , Pessoa de Meia-Idade , Tireoglobulina/imunologia , Hormônios Tireóideos/sangue , Adulto Jovem
3.
Mol Immunol ; 124: 218-228, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32615275

RESUMO

Autoreactive T cells may contribute to post-viral myocarditis induced with Coxsackievirus B3 (CVB3), but the underlying mechanisms of their generation are unclear. Here, we have comprehensively analyzed the generation of antigen-specific, autoreactive T cells in the mouse model of CVB3 infection for antigens implicated in patients with myocarditis/dilated cardiomyopathy. First, comparative analysis of CVB3 proteome with five autoantigens led us to identify three mimicry epitopes, one each from adenine nucleotide translocator 1 (ANT), sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2a (SERCA2a) and cardiac troponin I. None of these induced cross-reactive T cell responses. Next, we generated major histocompatibility complex (MHC) class II dextramers to enumerate the frequencies of antigen-specific T cells to determine whether T cells with multiple antigen specificities are generated by CVB3 infection. These analyses revealed appearance of CD4 T cells positive for SERCA2a 971-990, and cardiac myosin heavy chain-α (Myhc) 334-352 dextramers, both in the periphery and also in the hearts of CVB3-infected animals. While ANT 21-40 dextramer+ T cells were inconsistently detected, the ß1-adrenergic receptor 181-200/211-230 or branched chain α-ketoacid dehydrogenase kinase 111-130 dextramer+ cells were absent. Interestingly, SERCA2a 971-990, Myhc 334-352 and ANT 21-40 dextramer+ cells were also detected in the liver indicating that they may have a pathogenic role. Finally, we demonstrate that the SERCA2a 971-990-reactive T cells generated in CVB3 infection could transfer disease to naïve mice. The data suggest that CVB3 infection can lead to the generation of autoreactive T cells for multiple antigens indicating a possibility that the autoreactive T cells localized in the liver can potentially circulate and contribute to the development of viral myocarditis.


Assuntos
Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Infecções por Coxsackievirus/imunologia , Miocardite/imunologia , Miocardite/virologia , Animais , Autoimunidade/imunologia , Reações Cruzadas , Modelos Animais de Doenças , Enterovirus Humano B , Feminino , Masculino , Camundongos
4.
Neurology ; 95(10): e1426-e1436, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32641537

RESUMO

OBJECTIVE: To describe disease outcomes of myasthenia gravis (MG) subgroups and which factors influence outcomes by reviewing individual patient records of a representative cohort. METHODS: We performed a retrospective analysis of 199 patients with generalized MG and disease onset after the year 2000 who were treated at 2 tertiary referral centers in Austria. We stratified patients as early- and late-onset acetylcholine receptor antibody-positive, muscle-specific tyrosine kinase (MuSK) antibody-positive, and seronegative patients and patients with thymoma regardless of antibody status. We evaluated patients' symptom severity and treatment regimens and the occurrence of life-threatening events at yearly time points for up to 10 years. RESULTS: Minimal manifestation status or better was eventually achieved and sustained for >1 year by 125 (63%) patients. Forty percent (66 of 165 patients) showed an early response to treatment, which predicted a benign disease course later on. In contrast, 19% of patients, who remained symptomatic for 2 years after disease onset despite immunosuppressive therapy, were more treatment resistant in the following years. The strongest predictor of outcome was the diagnostic subgroup. Patients with MuSK-MG had a much better outcome than previously reported. CONCLUSION: Our data give an update on the disease course of generalized MG in the new century. Diagnostic subgroups and response to treatment within the first 2 years help to predict the long term outcome.


Assuntos
Miastenia Gravis/classificação , Adulto , Idoso , Autoanticorpos/imunologia , Autoantígenos/imunologia , Progressão da Doença , Feminino , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/imunologia , Prognóstico , Estudos Retrospectivos , Resultado do Tratamento
5.
Scand J Immunol ; 92(4): e12945, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32697368

RESUMO

In the past decades, clinical and experimental evidence has demonstrated that psoriasis is an immune-mediated inflammatory disease of the skin that occurs in genetically susceptible individuals. Psoriasis also shows clear autoimmune pathomechanisms, but specific cellular targets for the onset and maintenance of psoriatic lesions were not established until 2014. Since then, four psoriasis autoantigens were discovered, namely cathelicidin LL-37, melanocytic ADAMTSL5, lipid antigen PLA2G4D and keratin 17. Autoreactive T cells against these autoantigens were found in a number of patients with moderate-to-severe plaque psoriasis. Moreover, the discovery of autoantibodies against LL-37 and ADAMTSL5 and their strong association with psoriatic arthritis (PsA) suggest a potential role of these autoantibodies in the pathogenesis of PsA. This review discusses the current studies on psoriatic autoantigens and the associated circulating autoantibodies and their mechanisms involved in the development and maintenance of psoriatic plaques. Recent autoimmune evidence fuelled the discussion on psoriasis as an autoimmune skin disorder and has the potential to develop new treatment strategies with protective and therapeutic antigen-targeted methods.


Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/imunologia , Psoríase/imunologia , Proteínas ADAMTS/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos/imunologia , Autoimunidade/imunologia , Fosfolipases A2 do Grupo IV/imunologia , Humanos , Queratina-17/imunologia
6.
Autoimmun Rev ; 19(9): 102621, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32693029

RESUMO

Candida albicans is a commensal fungus with a potential pathogenicity and celiac disease is an autoimmune condition. Both share multiple pathophysiological junctions, including serological markers against cell-wall proteins of Candida, anti-gliadin antibodies are positive in both entities, gluten and a candidal virulence factor share sequence similarity and the autoantigen of celiac disease, the tissue transglutaminase, is pivotal in Candida albicans commensalism and hostile behavior and its covalently cross linked products are stable and resistant to breakdown in the two entities. Those autoimmune/infectious cross roads are the basis for the hypothesis that Candida albicans is an additional environmental factor for celiac disease autoimmunogenesis.


Assuntos
Candida albicans/patogenicidade , Doença Celíaca/microbiologia , Anticorpos/imunologia , Autoantígenos/química , Autoantígenos/imunologia , Autoimunidade , Candida albicans/imunologia , Doença Celíaca/imunologia , Gliadina/imunologia , Humanos , Transglutaminases/química , Transglutaminases/imunologia , Fatores de Virulência/química , Fatores de Virulência/imunologia
7.
Science ; 369(6501): 320-325, 2020 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-32675374

RESUMO

Restricted V(D)J recombination during fetal development was postulated to limit antibody repertoire breadth and prevent autoimmunity. However, newborn serum contains abundant autoantibodies, suggesting that B cell tolerance during gestation is not yet fully established. To investigate this apparent paradox, we evaluated the reactivities of more than 450 antibodies cloned from single B cells from human fetal liver, bone marrow, and spleen. We found that incomplete B cell tolerance in early human fetal life favored the accumulation of polyreactive B cells that bound both apoptotic cells and commensal bacteria from healthy adults. Thus, the restricted fetal preimmune repertoire contains potentially beneficial self-reactive innate-like B cell specificities that may facilitate the removal of apoptotic cells during development and shape gut microbiota assembly after birth.


Assuntos
Anticorpos/imunologia , Linfócitos B/imunologia , Feto/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Autoimunidade , Bactérias/imunologia , Feminino , Humanos , Imunidade Inata , Especificidade de Órgãos , Gravidez , Recombinação V(D)J
8.
PLoS One ; 15(6): e0234523, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525903

RESUMO

OBJECTIVE: Surfactant protein D (SP-D) is considered a serum biomarker of various forms of interstitial lung disease (ILD). In this study, we examined the utility of SP-D as a predictive biomarker for mortality in patients with ILD associated with polymyositis/dermatomyositis (PM/DM) using large-scale multicentre cohort data. METHODS: We enrolled 381 patients with incident PM/DM-associated ILD in a multicentre retrospective cohort based on the availability of serum SP-D at the baseline. Demographic and clinical characteristics as well as the presence of autoantibodies to melanoma differentiation-associated gene 5 (MDA5) and aminoacyl tRNA synthetase were measured at the time of diagnosis, and follow-up survival data were collected prospectively. RESULTS: Seventy-eight patients died during the median observation period of 18 months, and the majority of patients died of ILD. The SP-D levels at baseline were significantly lower (P = 0.02) in a non-survivor subset than in a survivor subset among the entire enrolled patients. However, the SP-D levels were higher in the non-survivor subset than in the survivor subset based on the stratification by anti-MDA5-positive, anti-ARS-positive and, double-negativity, although there was an only statistically significant difference (P = 0.01) in the double-negative group. Surprisingly, the SP-D levels were within the upper limit of normal, 110 ng/mL, in 54 (87%) of 62 anti-MDA5-positive patients who died. In the double-negative group, the mortality rates were significantly higher (P = 0.002) in a subset with SP-D ≥127.6 ng/mL, the cut-off value for mortality calculated by the receiver operating characteristic curve, than the other subset. All of patients with SP-D <127.6 ng/mL survived. CONCLUSION: Serum SP-D levels behave differently among patients with stratified by anti-MDA5 antibody, anti-ARS antibody and both negativity in PM/DM-associated ILD. Its use in clinical practice should be applied with caution on the basis of the presence or absence of anti-MDA5 antibody or anti-ARS antibody.


Assuntos
Autoanticorpos/sangue , Dermatomiosite/complicações , Doenças Pulmonares Intersticiais/mortalidade , Proteína D Associada a Surfactante Pulmonar/sangue , Adulto , Idoso , Aminoacil-tRNA Sintetases/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Biomarcadores/sangue , Dermatomiosite/sangue , Dermatomiosite/imunologia , Dermatomiosite/mortalidade , Estudos de Viabilidade , Feminino , Humanos , Helicase IFIH1 Induzida por Interferon/imunologia , Doenças Pulmonares Intersticiais/sangue , Doenças Pulmonares Intersticiais/etiologia , Doenças Pulmonares Intersticiais/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Valores de Referência , Estudos Retrospectivos , Análise de Sobrevida
9.
Nat Commun ; 11(1): 2859, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503973

RESUMO

Mature double negative (DN) T cells are a population of αß T cells that lack CD4 and CD8 coreceptors and contribute to systemic lupus erythematosus (SLE). The splenic marginal zone macrophages (MZMs) are important for establishing immune tolerance, and loss of their number or function contributes to the progression of SLE. Here we show that loss of MZMs impairs the tolerogenic clearance of apoptotic cells and alters the serum cytokine profile, which in turn provokes the generation of DN T cells from self-reactive CD8+ T cells. Increased Ki67 expression, narrowed TCR V-beta repertoire usage and diluted T-cell receptor excision circles confirm that DN T cells from lupus-prone mice and patients with SLE undergo clonal proliferation and expansion in a self-antigen dependent manner, which supports the shared mechanisms for their generation. Collectively, our results provide a link between the loss of MZMs and the expansion of DN T cells, and indicate possible strategies to prevent the development of SLE.


Assuntos
Autoantígenos/imunologia , Interleucina-17/metabolismo , Lúpus Eritematoso Sistêmico/imunologia , Subpopulações de Linfócitos T/imunologia , Transferência Adotiva , Animais , Autoantígenos/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Humanos , Tolerância Imunológica , Antígeno Ki-67/imunologia , Antígeno Ki-67/metabolismo , Lúpus Eritematoso Sistêmico/sangue , Macrófagos/imunologia , Camundongos , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Subpopulações de Linfócitos T/metabolismo
10.
PLoS One ; 15(6): e0233957, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32555697

RESUMO

INTRODUCTION: Autoantibodies (autoAbs) against desmoglein-1 (DSG1) and desmoglein-3 (DSG3) have conventionally been studied and well accepted in the pathogenesis of pemphigus vulgaris (PV) and foliaceus (PF). Recent studies have suggested that non-DSG autoAbs may contribute to the pathogenesis of pemphigus, including autoAbs directed at acetylcholine receptors (AChR) and thyroid peroxidase (TPO). The purpose of this study is to retrospectively analyze PV and PF patient sera to better understand the relationship between anti-AChR and -TPO Abs to disease activity and DSG reactivity between patients treated with prednisone and steroid sparing agents (SSA; n = 22) or prednisone and rituximab (n = 21). METHODS: Patients were evaluated at 2 time points, T1 and T2, for disease activity using the Pemphigus Disease Area Index (PDAI), and sera were tested for the presence of TPO, DSG1, DSG3, muscarinic (M3) and nicotinic (n) AChR IgG autoAbs, as well as antibodies against Varicella Zoster Virus (VZV) by ELISA. RESULTS: Disease activity significantly decreased in patients from T1 to T2 (p < .0001). A significant difference was seen in IgG anti-DSG1 (p < .0001) and anti-DSG3 (p = .0049) levels when T1 was compared to T2 in both treatment groups. A significant increase was found between pemphigus patients and normal subjects with nAChR (p < .0001) at T1 but not with m3AChR, TPO or VZV Abs. No significant difference was seen between T1 and T2 values in patients with pemphigus for the non-desmoglein Abs TPO (p = .7559), M3AChR (p = .9003), nAChR (p = .5143) or VZV (p = .2454). These findings demonstrate that although an increase in IgG anti-nAChR autoAbs was found in PV and PF subjects, these Abs did not decrease with treatment. No other non-DSG Abs were increased or significantly changed over time in patients with pemphigus. This suggests that anti -AChR and -TPO Abs may not play a direct role in the pathogenesis of most patients with pemphigus, but does not rule out a role for non-DSG auto antibodies in distinct subsets of pemphigus patient.


Assuntos
Autoanticorpos/sangue , Desmogleína 1/imunologia , Desmogleína 3/imunologia , Imunoglobulina G/sangue , Pênfigo/imunologia , Receptor Muscarínico M3/imunologia , Receptores Nicotínicos/imunologia , Adulto , Idoso , Autoantígenos/imunologia , Feminino , Humanos , Iodeto Peroxidase/imunologia , Proteínas de Ligação ao Ferro/imunologia , Masculino , Pessoa de Meia-Idade , Pênfigo/tratamento farmacológico , Prednisona/uso terapêutico , Estudos Retrospectivos , Rituximab/uso terapêutico , Adulto Jovem
11.
Neurology ; 95(1): e70-e78, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32487712

RESUMO

OBJECTIVES: The predominance of extramuscular manifestations (e.g., skin rash, arthralgia, interstitial lung disease [ILD]) as well as the low frequency of muscle signs in anti-melanoma differentiation-associated gene 5 antibody-positive (anti-MDA5+) dermatomyositis caused us to question the term myositis-specific antibody for the anti-MDA5 antibody, as well as the homogeneity of the disease. METHODS: To characterize the anti-MDA5+ phenotype, an unsupervised analysis was performed on anti-MDA5+ patients (n = 83/121) and compared to a group of patients with myositis without anti-MDA5 antibody (anti-MDA5-; n = 190/201) based on selected variables, collected retrospectively, without any missing data. RESULTS: Within anti-MDA5+ patients (n = 83), 3 subgroups were identified. One group (18.1%) corresponded to patients with a rapidly progressive ILD (93.3%; p < 0.0001 across all) and a very high mortality rate. The second subgroup (55.4%) corresponded to patients with pure dermato-rheumatologic symptoms (arthralgia; 82.6%; p < 0.01) and a good prognosis. The third corresponded to patients, mainly male (72.7%; p < 0.0001), with severe skin vasculopathy, frequent signs of myositis (proximal weakness: 68.2%; p < 0.0001), and an intermediate prognosis. Raynaud phenomenon, arthralgia/arthritis, and sex permit the cluster appurtenance (83.3% correct estimation). Nevertheless, an unsupervised analysis confirmed that anti-MDA5 antibody delineates an independent group of patients (e.g., dermatomyositis skin rash, skin ulcers, calcinosis, mechanic's hands, ILD, arthralgia/arthritis, and high mortality rate) distinct from anti-MDA5- patients with myositis. CONCLUSION: Anti-MDA5+ patients have a systemic syndrome distinct from other patients with myositis. Three subgroups with different prognosis exist.


Assuntos
Variação Biológica da População , Dermatomiosite/classificação , Dermatomiosite/imunologia , Helicase IFIH1 Induzida por Interferon/imunologia , Adulto , Autoanticorpos/imunologia , Autoantígenos/imunologia , Dermatomiosite/complicações , Feminino , Humanos , Pneumopatias/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Doenças Reumáticas/etiologia , Doenças Vasculares/etiologia
12.
Nat Commun ; 11(1): 2361, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398640

RESUMO

The development of thymic regulatory T cells (Treg) is mediated by Aire-regulated self-antigen presentation on medullary thymic epithelial cells (mTECs) and dendritic cells (DCs), but the cooperation between these cells is still poorly understood. Here we show that signaling through Toll-like receptors (TLR) expressed on mTECs regulates the production of specific chemokines and other genes associated with post-Aire mTEC development. Using single-cell RNA-sequencing, we identify a new thymic CD14+Sirpα+ population of monocyte-derived dendritic cells (CD14+moDC) that are enriched in the thymic medulla and effectively acquire mTEC-derived antigens in response to the above chemokines. Consistently, the cellularity of CD14+moDC is diminished in mice with MyD88-deficient TECs, in which the frequency and functionality of thymic CD25+Foxp3+ Tregs are decreased, leading to aggravated mouse experimental colitis. Thus, our findings describe a TLR-dependent function of mTECs for the recruitment of CD14+moDC, the generation of Tregs, and thereby the establishment of central tolerance.


Assuntos
Colite/imunologia , Células Dendríticas/imunologia , Células Epiteliais/imunologia , Linfócitos T Reguladores/imunologia , Timo/imunologia , Transferência Adotiva , Animais , Apresentação do Antígeno , Autoantígenos/imunologia , Separação Celular , Quimiocinas/imunologia , Quimiocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Citometria de Fluxo , Receptores de Lipopolissacarídeos/metabolismo , Camundongos , Receptores Imunológicos/metabolismo , Tolerância a Antígenos Próprios , Análise de Sequência de RNA , Transdução de Sinais/imunologia , Análise de Célula Única , Linfócitos T Reguladores/transplante , Timo/citologia , Receptores Toll-Like/metabolismo , Regulação para Cima
13.
Nat Commun ; 11(1): 2465, 2020 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32424289

RESUMO

Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare lymphoma of B-cell origin with frequent expression of functional B-cell receptors (BCRs). Here we report that expression cloning followed by antigen screening identifies DNA-directed RNA polymerase beta' (RpoC) from Moraxella catarrhalis as frequent antigen of BCRs of IgD+ LP cells. Patients show predominance of HLA-DRB1*04/07 and the IgVH genes encode extraordinarily long CDR3s. High-titer, light-chain-restricted anti-RpoC IgG1/κ-type serum-antibodies are additionally found in these patients. RpoC and MID/hag, a superantigen co-expressed by Moraxella catarrhalis that is known to activate IgD+ B cells by binding to the Fc domain of IgD, have additive activation effects on the BCR, the NF-κB pathway and the proliferation of IgD+ DEV cells expressing RpoC-specific BCRs. This suggests an additive antigenic and superantigenic stimulation of B cells with RpoC-specific IgD+ BCRs under conditions of a permissive MHC-II haplotype as a model of NLPHL lymphomagenesis, implying future treatment strategies.


Assuntos
Antígenos de Bactérias/imunologia , Linfócitos B/imunologia , Doença de Hodgkin/imunologia , Doença de Hodgkin/microbiologia , Moraxella catarrhalis/imunologia , Adolescente , Adulto , Idoso , Autoantígenos/imunologia , Linhagem Celular Tumoral , Proliferação de Células , Criança , RNA Polimerases Dirigidas por DNA/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Doença de Hodgkin/sangue , Humanos , Imunoglobulina D/metabolismo , Fragmentos Fab das Imunoglobulinas/imunologia , Região Variável de Imunoglobulina/genética , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Receptores de Antígenos de Linfócitos B/metabolismo
14.
Clin Immunol ; 217: 108480, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32461193

Assuntos
Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/epidemiologia , Betacoronavirus/imunologia , Infecções por Coronavirus/epidemiologia , Proteínas do Nucleocapsídeo/imunologia , Pandemias , Pneumonia Viral/epidemiologia , Glicoproteína da Espícula de Coronavírus/imunologia , Anticorpos Antivirais/química , Anticorpos Antivirais/genética , Autoanticorpos/química , Autoanticorpos/genética , Autoantígenos/química , Autoantígenos/genética , Doenças Autoimunes/etiologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/virologia , Autoimunidade , Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/virologia , Reações Cruzadas , Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Proteínas do Nucleocapsídeo/química , Proteínas do Nucleocapsídeo/genética , Pandemias/prevenção & controle , Pneumonia Viral/imunologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/virologia , Proteínas Associadas a Surfactantes Pulmonares/antagonistas & inibidores , Proteínas Associadas a Surfactantes Pulmonares/genética , Proteínas Associadas a Surfactantes Pulmonares/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Virais/efeitos adversos , Vacinas Virais/biossíntese
15.
Nat Immunol ; 21(5): 578-587, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32231298

RESUMO

The pool of beta cell-specific CD8+ T cells in type 1 diabetes (T1D) sustains an autoreactive potential despite having access to a constant source of antigen. To investigate the long-lived nature of these cells, we established a DNA methylation-based T cell 'multipotency index' and found that beta cell-specific CD8+ T cells retained a stem-like epigenetic multipotency score. Single-cell assay for transposase-accessible chromatin using sequencing confirmed the coexistence of naive and effector-associated epigenetic programs in individual beta cell-specific CD8+ T cells. Assessment of beta cell-specific CD8+ T cell anatomical distribution and the establishment of stem-associated epigenetic programs revealed that self-reactive CD8+ T cells isolated from murine lymphoid tissue retained developmentally plastic phenotypic and epigenetic profiles relative to the same cells isolated from the pancreas. Collectively, these data provide new insight into the longevity of beta cell-specific CD8+ T cell responses and document the use of this methylation-based multipotency index for investigating human and mouse CD8+ T cell differentiation.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Células-Tronco Pluripotentes/fisiologia , Adolescente , Adulto , Animais , Autoantígenos/imunologia , Plasticidade Celular , Células Cultivadas , Metilação de DNA , Epigênese Genética , Feminino , Citometria de Fluxo , Humanos , Memória Imunológica , Masculino , Camundongos , Análise de Célula Única , Adulto Jovem
16.
Eur J Paediatr Neurol ; 26: 89-91, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32340854

RESUMO

Autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy is a rare recently defined antibody-mediated encephalitis. Meningo-encephalomyelitis presentation is frequent with lymphocytic pleiocytosis in the cerebro-spinal fluid and brain MRI classically demonstrates in 50% of cases, a linear perivascular enhancement extending radially from the ventricles. Here, we describe 2 cases of pediatric autoimmune GFAP astrocytopathy with limbic encephalitis presentation and peculiar MRI characteristics: one with normal MRI and the second suggestive of Mild Encephalitis/Encephalopathy with reversible splenial lesion syndrome (MERS). These two cases illustrate that anti-GFAP antibodies should be sought in children presenting limbic encephalitis with a normal and/or MERS suggestive MRI, as treatment strategies may differ.


Assuntos
Astrócitos/patologia , Doenças Autoimunes/imunologia , Proteína Glial Fibrilar Ácida/imunologia , Encefalite Límbica/imunologia , Adolescente , Astrócitos/imunologia , Autoanticorpos/imunologia , Autoantígenos/imunologia , Doenças Autoimunes/patologia , Criança , Feminino , Humanos , Encefalite Límbica/patologia , Imagem por Ressonância Magnética , Masculino
17.
Nat Immunol ; 21(5): 567-577, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32284593

RESUMO

Unprimed mice harbor a substantial population of 'memory-phenotype' CD8+ T cells (CD8-MP cells) that exhibit hallmarks of activation and innate-like functional properties. Due to the lack of faithful markers to distinguish CD8-MP cells from bona fide CD8+ memory T cells, the developmental origins and antigen specificities of CD8-MP cells remain incompletely defined. Using deep T cell antigen receptor (TCR) sequencing, we found that the TCRs expressed by CD8-MP cells are highly recurrent and distinct from the TCRs expressed by naive-phenotype CD8+ T cells. CD8-MP clones exhibited reactivity to widely expressed self-ligands. T cell precursors expressing CD8-MP TCRs showed upregulation of the transcription factor Eomes during maturation in the thymus, prior to induction of the full memory phenotype, which is suggestive of a unique program triggered by recognition of self-ligands. Moreover, CD8-MP cells infiltrate oncogene-driven prostate tumors and express high densities of PD-1, which suggests potential roles in antitumor immunity and the response to immunotherapy.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Neoplasias da Próstata/imunologia , Receptores de Antígenos de Linfócitos T/genética , Proteínas com Domínio T/metabolismo , Timo/fisiologia , Animais , Autoantígenos/imunologia , Diferenciação Celular , Seleção Clonal Mediada por Antígeno , Células Clonais , Memória Imunológica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Receptor de Morte Celular Programada 1/metabolismo , Proteínas com Domínio T/genética , Regulação para Cima
18.
Rinsho Shinkeigaku ; 60(4): 264-267, 2020 Apr 24.
Artigo em Japonês | MEDLINE | ID: mdl-32238743

RESUMO

A 71-year-old man presented with progressive muscle weakness of the four limbs in November 2014. His symptoms had started from the left leg in 2008, resulting in frequent falls. In 2011, he became unable to stand up without a handrail due to weakness of the both legs. Physical examination showed almost symmetric muscle weakness of the arms and legs; MMT4. The CK level was slightly elevated of 304 IU/l. The patient was diagnosed as having inclusion body myositis based on the muscle biopsy findings showing many fibers with rimmed vacuoles in addition to mononuclear cell infiltrating into the endomysium, surrounding and sometimes invading into non-necrotic muscle fibers. Anti-PM/Scl-75 antibodies were positive. Muscle strength improved after intravenous immunoglobulin therapy, although the effect was only temporary. This rare case suggests the autoimmunological etiology in inclusion body myositis.


Assuntos
Autoanticorpos , Autoantígenos/imunologia , Imunoglobulinas Intravenosas/uso terapêutico , Miosite de Corpos de Inclusão/imunologia , Miosite de Corpos de Inclusão/terapia , Idoso , Humanos , Masculino , Debilidade Muscular/etiologia , Miosite de Corpos de Inclusão/complicações , Miosite de Corpos de Inclusão/diagnóstico
19.
Nat Rev Rheumatol ; 16(6): 301-315, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32341463

RESUMO

Peptidylarginine deiminases (PADs) have an important role in the pathogenesis of rheumatoid arthritis (RA) owing to their ability to generate citrullinated proteins - the hallmark autoantigens of RA. Of the five PAD enzyme isoforms, PAD2 and PAD4 are the most strongly implicated in RA at both genetic and cellular levels, and PAD inhibitors have shown therapeutic efficacy in mouse models of inflammatory arthritis. PAD2 and PAD4 are additionally targeted by autoantibodies in distinct clinical subsets of patients with RA, suggesting anti-PAD antibodies as possible biomarkers for RA diagnosis and prognosis. This Review weighs the evidence that supports a pathogenic role for PAD enzymes in RA as both promoters and targets of the autoimmune response, as well as discussing the mechanistic and therapeutic implications of these findings in the wider context of RA pathogenesis. Understanding the origin and consequences of dysregulated PAD enzyme activity and immune responses against PAD enzymes will be important to fully comprehend the pathogenic mechanisms involved in this disease and for the development of novel strategies to treat and prevent RA.


Assuntos
Anticorpos Anti-Proteína Citrulinada/imunologia , Artrite Reumatoide/imunologia , Proteína-Arginina Desiminase do Tipo 2/metabolismo , Proteína-Arginina Desiminase do Tipo 4/metabolismo , Artrite Reumatoide/enzimologia , Artrite Reumatoide/genética , Autoanticorpos/imunologia , Autoantígenos/imunologia , Autoantígenos/metabolismo , Citrulinação , Reações Cruzadas , Predisposição Genética para Doença , Humanos , Doenças Pulmonares Intersticiais/imunologia , Proteína-Arginina Desiminase do Tipo 2/genética , Proteína-Arginina Desiminase do Tipo 2/imunologia , Proteína-Arginina Desiminase do Tipo 3/imunologia , Proteína-Arginina Desiminase do Tipo 4/genética , Proteína-Arginina Desiminase do Tipo 4/imunologia , Desiminases de Arginina em Proteínas/genética , Desiminases de Arginina em Proteínas/imunologia , Desiminases de Arginina em Proteínas/metabolismo , Índice de Gravidade de Doença
20.
Transplant Proc ; 52(5): 1370-1375, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32245621

RESUMO

BACKGROUND: In simultaneous pancreas-kidney transplantation (SPKT), persistence or recurrence of pancreatic autoantibodies (PAs) has been associated with pancreas graft (PG) autoimmune-driven injury. Our aim was to analyze the impact of PAs on PG survival. METHODS: Between January 1, 2000, and December 31, 2017, we studied 139 patients with post-SPKT anti-glutamic acid decarboxylase (GAD) autoantibody. Alloimmune (ALI) events were defined as PG rejection and/or de novo donor-specific antibodies (DSA). Hence, 3 groups were defined: patients without ALI events or anti-GAD (n = 42), those with ALI events (n = 14), or those only with autoimmune events (positive for anti-GAD and no ALI events; n = 83). RESULTS: Male sex was predominant (n = 72, 52%). Median age was 35 years (interquartile range: 31-39) and median follow-up was 6-7 years (interquartile range: 4.1-9.2). Regarding anti-GAD positivity post-SPKT (n = 90, 65%), no differences were observed concerning age, sex, anti-HLA antibodies, HLA mismatch number and de novo DSA. ALI events were present in 10% (n = 14). PG survival 15 years post-SPKT was better in patients without immune events (96%) followed by those with ALI (69%) and autoimmune events (63%) (P = .025). Anti-GAD was associated to higher annualized mean Hb1AC (P = .006) and lower mean C-peptide (P = .013). According to pre- and post-SPKT anti-GAD status, conversion from negative to positive was associated to worse (63%) 10-year PG survival (P = .044), compared to persistence of negative (100%) or positive anti-GAD (88%). Anti-islet cell and anti-insulin autoantibodies had no impact. CONCLUSION: Anti-GAD presence post-SPKT was associated to higher pancreas disfunction and lower PG survival. De novo anti-GAD seems to offer a particular risk of PG failure.


Assuntos
Autoanticorpos/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Rim , Transplante de Pâncreas , Adulto , Autoantígenos/imunologia , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/imunologia , Feminino , Glutamato Descarboxilase/imunologia , Rejeição de Enxerto/imunologia , Humanos , Masculino , Pessoa de Meia-Idade
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