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1.
Nucleic Acids Res ; 48(19): 10890-10908, 2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-33021676

RESUMO

Although endogenous retroviruses (ERVs) are known to harbor cis-regulatory elements, their role in modulating cellular immune responses remains poorly understood. Using an RNA-seq approach, we show that several members of the ERV9 lineage, particularly LTR12C elements, are activated upon HIV-1 infection of primary CD4+ T cells. Intriguingly, HIV-1-induced ERVs harboring transcription start sites are primarily found in the vicinity of immunity genes. For example, HIV-1 infection activates LTR12C elements upstream of the interferon-inducible genes GBP2 and GBP5 that encode for broad-spectrum antiviral factors. Reporter assays demonstrated that these LTR12C elements drive gene expression in primary CD4+ T cells. In line with this, HIV-1 infection triggered the expression of a unique GBP2 transcript variant by activating a cryptic transcription start site within LTR12C. Furthermore, stimulation with HIV-1-induced cytokines increased GBP2 and GBP5 expression in human cells, but not in macaque cells that naturally lack the GBP5 gene and the LTR12C element upstream of GBP2. Finally, our findings suggest that GBP2 and GBP5 have already been active against ancient viral pathogens as they suppress the maturation of the extinct retrovirus HERV-K (HML-2). In summary, our findings uncover how human cells can exploit remnants of once-infectious retroviruses to regulate antiviral gene expression.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Retrovirus Endógenos/genética , Regulação da Expressão Gênica/imunologia , Infecções por HIV/genética , Regiões Promotoras Genéticas , Subpopulações de Linfócitos T/imunologia , Animais , Linfócitos T CD4-Positivos/citologia , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/imunologia , Células HEK293 , Infecções por HIV/imunologia , HIV-1 , Humanos , Macaca mulatta , Subpopulações de Linfócitos T/citologia
2.
Am J Gastroenterol ; 115(10): 1681-1688, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32558687

RESUMO

INTRODUCTION: Diagnosed celiac disease (CD) is associated with lymphoproliferative malignancy and gastrointestinal cancer, but little is known about the long-term consequences of undiagnosed CD. We aimed to investigate long-term consequences of undiagnosed CD for mortality and incidence of cancer and other chronic diseases. METHODS: We screened biobank serum samples for immunoglobulin (Ig) A and IgG tissue transglutaminase (TTG) and IgG deamidated gliadin peptide in a study of 8 population-based cohort studies comprising 16,776 participants examined during 1976-2012 and followed with >99% complete follow-up in Danish nationwide registries until December 31, 2017, regarding vital status and incidence of diseases. Undiagnosed CD was defined as antibody positivity (IgA-TTG or IgG-TTG ≥ 7 U/mL and/or IgG deamidated gliadin peptide ≥ 10 U/mL) in individuals without a diagnosis of CD recorded in the National Patient Register. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated by Cox regression analyses with age as the underlying time scale. RESULTS: The prevalence of undiagnosed CD was 1.0% with no statistically significant increase over time. Undiagnosed CD was associated with increased risk of cancer overall (HR, 1.57; 95% CI, 1.16-2.11), gastrointestinal cancer (HR, 2.33; 95% CI, 1.35-4.04), cancer of the uterus (HR, 3.95; 95% CI, 1.46-10.69), breast cancer (HR, 1.98; 95% CI, 1.02-3.82), head and neck cancer (HR, 3.12; 95% CI, 1.15-8.43), and cardiovascular disease (HR, 1.37; 95% CI, 1.01-1.85). We found no statistically significant association between undiagnosed CD and mortality (HR, 1.19; 95% CI, 0.87-1.61). DISCUSSION: Undiagnosed CD was associated with increased risk of cardiovascular disease and cancer suggesting that untreated CD has serious long-term health consequences not only affecting the gastrointestinal tract (see Visual Abstract, Supplementary Digital Content, http://links.lww.com/AJG/B566).


Assuntos
Doenças Cardiovasculares/epidemiologia , Doença Celíaca/epidemiologia , Mortalidade , Neoplasias/epidemiologia , Doenças não Diagnosticadas/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos/imunologia , Autoanticorpos/imunologia , Bancos de Espécimes Biológicos , Neoplasias da Mama/epidemiologia , Doença Celíaca/imunologia , Dinamarca/epidemiologia , Feminino , Proteínas de Ligação ao GTP/imunologia , Neoplasias Gastrointestinais/epidemiologia , Gliadina/imunologia , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Modelos de Riscos Proporcionais , Fatores de Risco , Transglutaminases/imunologia , Neoplasias Uterinas/epidemiologia , Adulto Jovem
3.
Nat Immunol ; 21(8): 880-891, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32541830

RESUMO

Bacterial lipopolysaccharide triggers human caspase-4 (murine caspase-11) to cleave gasdermin-D and induce pyroptotic cell death. How lipopolysaccharide sequestered in the membranes of cytosol-invading bacteria activates caspases remains unknown. Here we show that in interferon-γ-stimulated cells guanylate-binding proteins (GBPs) assemble on the surface of Gram-negative bacteria into polyvalent signaling platforms required for activation of caspase-4. Caspase-4 activation is hierarchically controlled by GBPs; GBP1 initiates platform assembly, GBP2 and GBP4 control caspase-4 recruitment, and GBP3 governs caspase-4 activation. In response to cytosol-invading bacteria, activation of caspase-4 through the GBP platform is essential to induce gasdermin-D-dependent pyroptosis and processing of interleukin-18, thereby destroying the replicative niche for intracellular bacteria and alerting neighboring cells, respectively. Caspase-11 and GBPs epistatically protect mice against lethal bacterial challenge. Multiple antagonists of the pathway encoded by Shigella flexneri, a cytosol-adapted bacterium, provide compelling evolutionary evidence for the importance of the GBP-caspase-4 pathway in antibacterial defense.


Assuntos
Caspases Iniciadoras/imunologia , Proteínas de Ligação ao GTP/imunologia , Infecções por Bactérias Gram-Negativas/imunologia , Inflamassomos/imunologia , Transdução de Sinais/imunologia , Animais , Bactérias Gram-Negativas/imunologia , Células HeLa , Humanos , Lipopolissacarídeos/imunologia , Camundongos , Piroptose/imunologia
5.
PLoS Pathog ; 16(5): e1008553, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453761

RESUMO

IRGM and its mouse orthologue Irgm1 are dynamin-like proteins that regulate vesicular remodeling, intracellular microbial killing, and pathogen immunity. IRGM dysfunction is linked to inflammatory bowel disease (IBD), and while it is thought that defective intracellular killing of microbes underscores IBD susceptibility, studies have yet to address how IRGM/Irgm1 regulates immunity to microbes relevant to intestinal inflammation. Here we find that loss of Irgm1 confers marked susceptibility to Citrobacter rodentium, a noninvasive intestinal pathogen that models inflammatory responses to intestinal bacteria. Irgm1-deficient mice fail to control C. rodentium outgrowth in the intestine, leading to systemic pathogen spread and host mortality. Surprisingly, susceptibility due to loss of Irgm1 function was not linked to defective intracellular killing of C. rodentium or exaggerated inflammation, but was instead linked to failure to remodel specific colon lamina propria (C-LP) myeloid cells that expand in response to C. rodentium infection and are essential for C. rodentium immunity. Defective immune remodeling was most striking in C-LP monocytes, which were successfully recruited to the infected C-LP, but subsequently underwent apoptosis. Apoptotic susceptibility was induced by C. rodentium infection and was specific to this setting of pathogen infection, and was not apparent in other settings of intestinal inflammation. These studies reveal a novel role for Irgm1 in host defense and suggest that deficiencies in survival and remodeling of C-LP myeloid cells that control inflammatory intestinal bacteria may underpin IBD pathogenesis linked to IRGM dysfunction.


Assuntos
Citrobacter rodentium/imunologia , Colo/imunologia , Infecções por Enterobacteriaceae/imunologia , Proteínas de Ligação ao GTP/deficiência , Doenças Inflamatórias Intestinais/imunologia , Monócitos/imunologia , Animais , Colo/microbiologia , Colo/patologia , Infecções por Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/patologia , Proteínas de Ligação ao GTP/imunologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Knockout , Monócitos/microbiologia , Monócitos/patologia , Membrana Mucosa/imunologia , Membrana Mucosa/microbiologia , Membrana Mucosa/patologia
6.
Mol Immunol ; 121: 1-6, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32135400

RESUMO

The transglutaminase 2 (TG2) is one of the enigmatic enzymes with important functional diversity. It plays an important role in several pathologies such as celiac disease (CD). In patients with active CD, the abnormal retrotranscytosis of IgA/gliadin complexes is mediated by Transferrin Receptor 1 (TfR1). This triad association takes also place in IgA nephropathy (IgA-N). IgA-N is characterized by the formation of nephrotoxic complexes of IgA1 and soluble CD89 (sCD89). These complexes are abnormally deposited in the kidney. Using a humanized mouse model of IgA-N (α1KI-CD89Tg), we showed that IgA1-sCD89 complexes engender mesangial cell activation and proliferation with TfR1 and TG2 up-regulation, associated with IgA-N features. This TG2-TfR1 interaction enhances mesangial IgA1 deposition promoting inflammation. Humanized α1KI-CD89Tg mice deficient for TG2 show a decrease in TfR1 expression in kidney leading to reduced IgA1-sCD89 deposits and an improvement in IgA-N features. Moreover, TG2 is active and overexpressed in the intestine of IgA-N mice and gliadin participates to this renal pathology. In kidney as in intestine, the TG2 has a crucial role in the cooperation between TfR1-IgA and a central role in the pathogenic amplification.


Assuntos
Antígenos CD/metabolismo , Proteínas de Ligação ao GTP/metabolismo , Gliadina/imunologia , Glomerulonefrite por IGA/imunologia , Imunoglobulina A/metabolismo , Receptores da Transferrina/metabolismo , Transglutaminases/metabolismo , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Doença Celíaca/imunologia , Doença Celíaca/patologia , Modelos Animais de Doenças , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/imunologia , Gliadina/metabolismo , Humanos , Imunoglobulina A/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Células Mesangiais/imunologia , Células Mesangiais/patologia , Camundongos , Camundongos Transgênicos , Receptores Fc/genética , Receptores Fc/imunologia , Receptores Fc/metabolismo , Receptores da Transferrina/imunologia , Transglutaminases/genética , Transglutaminases/imunologia , Regulação para Cima/imunologia
7.
PLoS Pathog ; 16(3): e1008364, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32150572

RESUMO

Innate immunity responds to pathogens by producing alarm signals and activating pathways that make host cells inhospitable for pathogen replication. The intracellular bacterium Burkholderia thailandensis invades the cytosol, hijacks host actin, and induces cell fusion to spread to adjacent cells, forming multinucleated giant cells (MNGCs) which promote bacterial replication. We show that type I interferon (IFN) restricts macrophage MNGC formation during B. thailandensis infection. Guanylate-binding proteins (GBPs) expressed downstream of type I IFN were required to restrict MNGC formation through inhibition of bacterial Arp2/3-dependent actin motility during infection. GTPase activity and the CAAX prenylation domain were required for GBP2 recruitment to B. thailandensis, which restricted bacterial actin polymerization required for MNGC formation. Consistent with the effects in in vitro macrophages, Gbp2-/-, Gbp5-/-, GbpChr3-KO mice were more susceptible to intranasal infection with B. thailandensis than wildtype mice. Our findings reveal that IFN and GBPs play a critical role in restricting cell-cell fusion and bacteria-induced pathology during infection.


Assuntos
Infecções por Burkholderia/imunologia , Burkholderia/imunologia , Proteínas de Ligação ao GTP/imunologia , Células Gigantes/imunologia , Macrófagos/imunologia , Doenças Nasais/imunologia , Prenilação de Proteína/imunologia , Animais , Infecções por Burkholderia/genética , Infecções por Burkholderia/patologia , Fusão Celular , Proteínas de Ligação ao GTP/genética , Células Gigantes/microbiologia , Células Gigantes/patologia , Interferon Tipo I/genética , Interferon Tipo I/imunologia , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Camundongos Knockout , Doenças Nasais/genética , Doenças Nasais/microbiologia , Doenças Nasais/patologia
8.
Clin Lab ; 66(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32013344

RESUMO

BACKGROUND: This study aimed to assess the declared benefits of the new test using antibodies against tissue transglutaminase in complex with gliadin representing a neo-epitope in the IgA and IgG class of immunoglobulins compared with currently used tissue transglutaminase antibodies in the IgA class of immunoglobulins among children. METHODS: In the cross-sectional study (P1 study, n = 406) and two small-size prospective observational studies (P2 study, n = 59 and P3 study, n = 12), serum samples from all children were simultaneously tested for endomysial antibodies, IgA tissue transglutaminase antibodies, and antibodies against tissue transglutaminase in complex with gliadin in the IgA and IgG class of immunoglobulins. The exact McNemar test, Wilcoxon test, and Spearman's correlation coefficient were used to analyze the data. RESULTS: We found a significant asymmetry of the tissue transglutaminase antibodies test compared with the antibodies against tissue transglutaminase neo-epitope test (P1). More patients (1.5%) had tissue transglutaminase an¬tibodies positive and antibodies against tissue transglutaminase neo-epitope negative results, whereas no patients had tissue transglutaminase antibodies negative and antibodies against tissue transglutaminase neo-epitope positive results. Of 59 children with tissue transglutaminase antibodies and/or endomysial antibodies positive results (P2), one (1.7%) did not have celiac disease. In agreement with the P1 study, four patients (6.8%) with confirmed celiac disease were tissue transglutaminase antibodies positive and antibodies against tissue transglutaminase neo-epitope negative. In this group, the sensitivity of the antibodies against tissue transglutaminase neo-epitope test for diagnosis of celiac disease was 91.4% (95% confidence interval, 81.0 - 97.1%). Among children diagnosed with functional gastrointestinal disorder (P3), all had negative serological test results, and none was diagnosed with celiac disease. CONCLUSIONS: The results do not indicate that antibodies against tissue transglutaminase neo-epitope test would be an unambiguously better test than the currently used tissue transglutaminase antibodies.


Assuntos
Autoanticorpos/sangue , Doença Celíaca/diagnóstico , Proteínas de Ligação ao GTP/imunologia , Transglutaminases/imunologia , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Masculino , Estudos Prospectivos
9.
Nutrients ; 12(2)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069794

RESUMO

Dermatitis herpetiformis (DH), a cutaneous manifestation of coeliac disease, is characterized by transglutaminase (TG) 3-targeted dermal immunoglobulin A (IgA) deposits. The treatment for DH is the same as for coeliac disease, namely a life-long gluten-free diet. DH patients typically have gluten-dependent circulating autoantibodies targeting TG3 and TG2, and plasma cells secreting such autoantibodies have been detected in the small intestinal mucosa. This study investigates the gluten-responsiveness of intestinal TG3 and TG2 antibody-secreting plasma cells in 16 treated DH patients undergoing a gluten challenge. The frequency of both plasma cell populations increased significantly during the challenge, and their frequency correlated with the corresponding serum autoantibody levels at post-challenge. TG3-specific plasma cells were absent in all 18 untreated coeliac disease patients and seven non-coeliac control subjects on gluten-containing diets. These findings indicate that, in DH, both intestinal TG3- and TG2-antibody secreting plasma cells are gluten-dependent, and that TG3-antibody secreting plasma cells are DH-specific.


Assuntos
Autoanticorpos/sangue , Dermatite Herpetiforme/imunologia , Proteínas de Ligação ao GTP/imunologia , Glutens/efeitos adversos , Plasmócitos/imunologia , Transglutaminases/imunologia , Adulto , Idoso , Doença Celíaca/complicações , Doença Celíaca/imunologia , Dieta Livre de Glúten , Feminino , Glutens/imunologia , Humanos , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Masculino , Pessoa de Meia-Idade
10.
Clin Transl Gastroenterol ; 11(1): e00121, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31977451

RESUMO

INTRODUCTION: Celiac disease (CD) is common, affecting approximately 1% of the population. The cornerstone of management is a gluten-free diet, with dietetic advice being the key to aiding implementation. The aim of the study was to assess group clinics in comparison with traditional individual appointments. METHODS: Patients with a new diagnosis of CD, confirmed histologically, were prospectively recruited over 18 months in Sheffield, United Kingdom. Patients received either a group clinic or traditional one-to-one appointment, led by a dietitian. Quality-of-life questionnaires were completed at baseline, as well as biochemical parameters being recorded. Patients were followed up at 3 months, where adherence scores were assessed as well as biochemical parameters and quality of life questionnaires being completed. RESULTS: Sixty patients with CD were prospectively recruited and received either an individual (n = 30) or group clinic (n = 30). A statistically significant reduction in tissue transglutaminase was noted following group clinics (mean 58.5, SD 43.4 U/mL vs mean 13.2, SD 5.7 U/mL, P < 0.01). No significant differences in baseline and follow-up biochemical parameters between one-to-one and group clinics were noted. At follow-up, there was no statistically significant difference between mean gluten-free diet adherence scores (mean 3.1, SD 0.4 vs mean 3.1, SD 0.7, P = 0.66) between one-to-one and group clinics. DISCUSSION: This first study assessing group clinics in CD demonstrates they are as effective as traditional one-to-one clinics, with the added benefits of peer support and greater efficiency, with an estimated 54% reduction of dietetic resources.


Assuntos
Doença Celíaca/dietoterapia , Nutricionistas , Grupo Associado , Consultas Médicas Compartilhadas , Apoio Social , Cooperação e Adesão ao Tratamento/estatística & dados numéricos , Adulto , Idoso , Ansiedade/psicologia , Doença Celíaca/imunologia , Doença Celíaca/fisiopatologia , Doença Celíaca/psicologia , Depressão/psicologia , Feminino , Proteínas de Ligação ao GTP/imunologia , Humanos , Imunoglobulina A/imunologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Transglutaminases/imunologia , Resultado do Tratamento , Reino Unido
11.
Gastroenterology ; 158(1): 151-159.e3, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31560892

RESUMO

BACKGROUND & AIMS: Celiac disease can develop at any age, but outcomes of adults with positive results from serologic tests for tissue transglutaminase antibodies (tTGA) without endoscopic determination of celiac disease (called celiac autoimmunity) have not been thoroughly evaluated. We investigated the proportion of adults with celiac autoimmunity at a community medical center and their progression to celiac disease. METHODS: We analyzed waste blood samples from a community clinic from 15,551 adults for tTGA and, if titer results were above 2 U/mL, for endomysial antibody. The blood samples had been collected at 2 time points (median interval, 8.8 years) from 2006 through 2017. We collected data from the clinic on diagnoses of celiac disease based on duodenal biopsy analysis. RESULTS: Of the serum samples collected at the first time point, 15,398 had negative results for tTGA, and 153 had positive results for tTGA (>4 U/mL). Based on medical records, 6 individuals received a diagnosis of celiac disease, for a cumulative incidence of celiac disease diagnosis of 0.06% (95% confidence interval, 0.01-0.11). Forty-nine (0.32%) individuals with a negative result from the first serologic test for tTGA had a positive result from the second test. Among the 153 adults who were tTGA positive at the first time point, 31 (20%) had a subsequent diagnosis of celiac disease, 81 (53%) remained positive for tTGA without a clinical diagnosis of celiac disease, and 41 (27%) had negative test results for tTGA at the second time point. Higher initial tTGA titers, female sex, and a history of hypothyroidism and autoimmune disease were associated with increased risks of subsequent diagnosis of celiac disease. Interestingly, adults whose first blood sample had a positive test result but second blood sample had a negative result for tTGA were older, had lower-than-average initial tTGA titer results, and had a higher mean body mass index than adults whose blood samples were positive for tTGA at both time points and adults later diagnosed with celiac disease. CONCLUSIONS: In an analysis of serum samples collected from a community clinic an average of 8.8 years apart, we found that fewer than 1% of adults with negative results from an initial test for tTGA have a positive result on a second test. Of adults with positive results from the test for tTGA, only 20% are later diagnosed with celiac disease; the remaining individuals maintain persistent increases in tTGA without diagnoses of celiac disease or have negative results from second tests.


Assuntos
Autoanticorpos/sangue , Autoimunidade , Doença Celíaca/epidemiologia , Centros Comunitários de Saúde/estatística & dados numéricos , Proteínas de Ligação ao GTP/imunologia , Transglutaminases/imunologia , Adulto , Autoanticorpos/imunologia , Biópsia , Doença Celíaca/diagnóstico , Doença Celíaca/imunologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Minnesota/epidemiologia , Estudos Prospectivos , Estudos Soroepidemiológicos
12.
Clin Exp Immunol ; 199(3): 294-302, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31663117

RESUMO

Tissue transglutaminase (tTG) and microbial transglutaminase (mTG) cross-link gliadins to form complexes that expose immunogenic neo-epitopes to produce tTG and mTG-neo-epitope antibodies. The aim of this study was to test the diagnostic performance of antibodies against non-complexed and complexed forms of transglutaminases, to correlate their activities to the intestinal damage and to explore age group dependency in celiac disease (CD). A total of 296 children with untreated CD and 215 non-celiac disease controls were checked by in-house enzyme-linked immunosorbent assays detecting immunoglobulin (Ig)A, IgG or combined detection of IgA and IgG (check) against tTG, AESKULISA® tTG New Generation (tTG-neo) and mTG-neo (RUO), IgA and IgG antibodies against deamidated gliadin peptide (DGP) and human IgA anti-endomysium antibodies (EMA) using AESKUSLIDES® EMA. Intestinal pathology was graded according the revised Marsh criteria, and age dependencies of the antibody activities were analysed. Using cut-offs estimated from receiver operating characteristic (ROC) curves, the highest area under curve (AUC) of the TG assays was 0·963 for tTG-neo check, followed by tTG check (0·962) when the diagnosis was based on enteric mucosal histology. tTG-neo check was the most effective to reflect the intestinal abnormalities in CD (r = 0·795, P < 0·0001). High levels of anti-mTG-neo IgG and anti-tTG-neo IgG appeared in the earlier age groups, as compared to anti-tTG IgG (P < 0·001). Considering antibody diagnostic performance based on AUC, enteric damage reflection and predictability at an early age, the anti-neo tTG check was the most effective diagnostic biomarker for pediatric CD. The mTG neo check might represent a new marker for CD screening, diagnosis and predictability.


Assuntos
Autoanticorpos/análise , Biomarcadores/análise , Doença Celíaca/imunologia , Epitopos/imunologia , Proteínas de Ligação ao GTP/imunologia , Transglutaminases/imunologia , Adolescente , Autoanticorpos/imunologia , Proteínas de Bactérias/imunologia , Doença Celíaca/diagnóstico , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Gliadina/imunologia , Humanos , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Lactente , Masculino , Curva ROC
13.
Dig Dis Sci ; 65(7): 1982-1991, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31781909

RESUMO

BACKGROUND: The role of microRNAs (miRNAs) in celiac disease (CD) is unclear. AIMS: We evaluated inflammation-related miRNA-146a, miRNA-155, miRNA-21, and miRNA-125b expression in peripheral blood and intestinal mucosa of CD adults. METHODS: Thirty patients with CD were included: patients with active CD on a gluten-containing diet (CD-active, n = 10), patients on a gluten-free diet (for at least 1 year), and patients with negative blood antibodies (CD-inactivePE, n = 10). In addition, ten healthy volunteers formed the comparison/control group. MiRNA expression was measured in duodenal biopsies from patients (CD-inactiveMU, n = 10) after in vitro exposure to PT gliadin and 33-mer peptide. MiRNAs expression was measured in plasma and in peripheral blood mononuclear cells (PBMCs) and monocytes, before and after in vitro exposure to native gliadin (gliadinN). RESULTS: Expression levels of miRNA-146a, miRNA-155, and miRNA-21 in PBMCs, miRNA-155 in monocytes and miRNA-155, miRNA-21, and miRNA-125b in plasma were elevated in both groups of celiac patients. After in vitro exposure with gliadinN, miRNA-146a and miRNA-155 expression markedly increased in PBMCs and monocytes, while miRNA-155 and miRNA-21 increased in the CD-active group. MiRNAs expression in intestinal mucosa did not change. MiRNA-146a and miRNA-155 expression showed high sensitivity and specificity for the presence of CD, irrespective of the current dietary treatment. CONCLUSIONS: Selected inflammation-related miRNAs expression is elevated in the peripheral blood of celiac. This suggests their participation in the immune processes underlying the pathology. Their similar response in active and inactive CD suggests that they should be further evaluated, as potential diagnostic biomarkers for CD.


Assuntos
Doença Celíaca/metabolismo , Mucosa Intestinal/metabolismo , MicroRNAs/metabolismo , Adulto , Estudos de Casos e Controles , Doença Celíaca/sangue , Doença Celíaca/dietoterapia , Doença Celíaca/imunologia , Dieta Livre de Glúten , Feminino , Proteínas de Ligação ao GTP/imunologia , Antígenos HLA-DQ/genética , Humanos , Imunoglobulina A/imunologia , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Transglutaminases/imunologia
14.
J Exp Med ; 217(2)2020 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-31727780

RESUMO

Autoantibodies to transglutaminase 2 (TG2) are hallmarks of celiac disease. To address B cell tolerance and autoantibody formation to TG2, we generated immunoglobulin knock-in (Ig KI) mice that express a prototypical celiac patient-derived anti-TG2 B cell receptor equally reactive to human and mouse TG2. We studied B cell development in the presence/absence of autoantigen by crossing the Ig KI mice to Tgm2-/- mice. Autoreactive B cells in Tgm2+/+ mice were indistinguishable from their naive counterparts in Tgm2-/- mice with no signs of clonal deletion, receptor editing, or B cell anergy. The autoreactive B cells appeared ignorant to their antigen, and they produced autoantibodies when provided T cell help. The findings lend credence to a model of celiac disease where gluten-reactive T cells provide help to autoreactive TG2-specific B cells by involvement of gluten-TG2 complexes, and they outline a general mechanism of autoimmunity with autoantibodies being produced by ignorant B cells on provision of T cell help.


Assuntos
Formação de Anticorpos/genética , Autoanticorpos/imunologia , Autoantígenos/imunologia , Linfócitos B/imunologia , Doença Celíaca/imunologia , Proteínas de Ligação ao GTP/imunologia , Tolerância Imunológica/genética , Transglutaminases/imunologia , Animais , Autoantígenos/genética , Autoimunidade , Linfócitos T CD4-Positivos/imunologia , Doença Celíaca/patologia , Proteínas de Ligação ao GTP/genética , Técnicas de Introdução de Genes , Glutens/imunologia , Células HEK293 , Humanos , Ativação Linfocitária/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos B/imunologia , Transglutaminases/genética
15.
PLoS One ; 14(11): e0225851, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31770411

RESUMO

The diagnosis of celiac disease (CD) is currently based on serology and intestinal biopsy, with detection of anti-tissue transglutaminase (tTG) IgA antibodies recommended as the first-line test. Emphasizing the increasing importance of serological testing, new guidelines and evidence suggest basing the diagnosis solely on serology without confirmatory biopsy. Enzyme immunoassays (EIAs) are the established approach for anti-tTG antibody detection, with the existing point-of-care (POC) tests lacking sensitivity and/or specificity. Improved POC methods could help reduce the underdiagnosis and diagnostic delay of CD. We have previously developed rapid homogenous immunoassays based on time-resolved Förster resonance energy transfer (TR-FRET), and demonstrated their suitability in serodiagnostics with hanta- and Zika virus infections as models. In this study, we set out to establish a protein L -based TR-FRET assay (LFRET) for the detection of anti-tTG antibodies. We studied 74 patients with biopsy-confirmed CD and 70 healthy controls, with 1) the new tTG-LFRET assay, and for reference 2) a well-established EIA and 3) an existing commercial POC test. IgG depletion was employed to differentiate between anti-tTG IgA and IgG positivity. The sensitivity and specificity of the first-generation tTG-LFRET POC assay in detection of CD were 87.8% and 94.3%, respectively, in line with those of the reference POC test. The sensitivity and specificity of EIA were 95.9% and 91.9%, respectively. This study demonstrates the applicability of LFRET to serological diagnosis of autoimmune diseases in general and of CD in particular.


Assuntos
Autoanticorpos/sangue , Doença Celíaca/diagnóstico , Proteínas de Ligação ao GTP/imunologia , Imunoensaio/métodos , Transglutaminases/imunologia , Adulto , Estudos de Casos e Controles , Criança , Ensaio de Imunoadsorção Enzimática , Transferência Ressonante de Energia de Fluorescência , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/metabolismo , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Sensibilidade e Especificidade , Transglutaminases/genética , Transglutaminases/metabolismo
16.
Eur Rev Med Pharmacol Sci ; 23(18): 8084-8086, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31599434

RESUMO

We present a woman with a three-year history of severe chronic urticaria and recurrent vulvo-vaginal Candidiasis in the setting of seasonal allergic rhinitis. Her past medical history was significant only for Bell's palsy in her childhood. Her review of systems was otherwise negative (specifically: no history of diarrhea, weight loss, malabsorption, anemia, nor eczema). Extensive testing revealed seasonal sensitivities to outdoor allergens and celiac disease. Repeating the evaluation six months after initiating a wheat-free diet, her vulvo-vaginal symptoms resolved.


Assuntos
Candidíase Vulvovaginal/imunologia , Doença Celíaca/imunologia , Urticária Crônica/imunologia , Rinite Alérgica Sazonal/imunologia , Ambrosia , Candidíase Vulvovaginal/complicações , Doença Celíaca/complicações , Doença Celíaca/diagnóstico , Doença Celíaca/dietoterapia , Doença Crônica , Urticária Crônica/complicações , Dieta Livre de Glúten , Duodeno/patologia , Feminino , Fissura Anal/etiologia , Proteínas de Ligação ao GTP/imunologia , Gliadina/imunologia , Humanos , Imunoglobulina A/imunologia , Testes Intradérmicos , Pessoa de Meia-Idade , Poaceae , Rinite Alérgica Sazonal/complicações , Transglutaminases/imunologia , Árvores
17.
ACS Sens ; 4(11): 2937-2944, 2019 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-31612712

RESUMO

Salmon fish farmers face remarkable problems in fish rearing and handling due to the spread of disease by infectious pancreatic necrosis virus (IPNV). Therefore, we developed a straightforward and sensitive technique to detect IPNV-based on recombinant human apoferritin heavy chain (hAFN-H) protein nanoparticles. In this study, the 24 subunits of the hAFN-H were genetically modified to express 6×His-tag and protein-G at their C-terminal site using Escherichia coli. We thus achieved a two-step signal amplifying strategy that utilizes a recombinant hAFN-H nanoprobe having a protein-G-binding site that targets the Fc region of monoclonal antibodies and a 6×His-tag that actively interacts with the functionalized Ni-NTA derivatives. In this study, we report a considerable advancement in magnetic bead-based detection systems that use Ni-NTA-Atto 550, reliably exhibiting detection limits of 1.02 TCID50/mL (50% tissue culture infective dose). Additionally, we propose a lateral flow chip-based detection method that uses the hAFN-H surface functionalized with 5 nm of the Ni-NTA-nanogold complex as a nanoprobe; the limit of detection towards IPNV was 0.88 TCID50/mL. The detection of IPNV by this recombinant hAFN-H nanoprobe was linear to virus titers in the range of 101-103 TCID50/mL.


Assuntos
Técnicas Biossensoriais/métodos , Corantes Fluorescentes/química , Imunoensaio/métodos , Vírus da Necrose Pancreática Infecciosa/isolamento & purificação , Nanopartículas/química , Anticorpos Imobilizados/imunologia , Anticorpos Monoclonais/imunologia , Apoferritinas/química , Apoferritinas/genética , Apoferritinas/imunologia , Técnicas Biossensoriais/instrumentação , Escherichia coli/genética , Fluorometria/métodos , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/imunologia , Humanos , Vírus da Necrose Pancreática Infecciosa/imunologia , Limite de Detecção , Fenômenos Magnéticos , Papel , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
18.
Nutrients ; 11(10)2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31547042

RESUMO

Celiac disease (CD) is a chronic inflammation of the small intestine triggered by the ingestion of gluten in genetically predisposed individuals. Tissue transglutaminase (TG2) is a key factor in CD pathogenesis, because it catalyzes both the deamidation of specific glutamine residues and the formation of covalent Nε-(γ-glutamyl)-lysine isopeptide crosslinks resulting in TG2-gluten peptide complexes. These complexes are thought to activate B cells causing the secretion of anti-TG2 autoantibodies that serve as diagnostic markers for CD, although their pathogenic role remains unclear. To gain more insight into the molecular structures of TG2-gluten peptide complexes, we used different proteomics software tools that enable the comprehensive identification of isopeptides. Thus, 34 different isopeptides involving 20 TG2 lysine residues were identified in a model system, only six of which were previously known. Additionally, 36 isopeptides of TG2-TG2 multimers were detected. Experiments with different TG2-gluten peptide molar ratios revealed the most preferred lysine residues involved in isopeptide crosslinking. Expanding the model system to three gluten peptides with more glutamine residues allowed the localization of the preferred glutamine crosslinking sites. These new insights into the structure of TG2-gluten peptide complexes may help clarify the role of extracellular TG2 in CD autoimmunity and in other inflammatory diseases.


Assuntos
Sequência de Aminoácidos , Proteínas de Ligação ao GTP/química , Glutens/química , Peptídeos/química , Transglutaminases/química , Autoanticorpos/química , Autoanticorpos/imunologia , Linfócitos B/imunologia , Doença Celíaca/imunologia , Proteínas de Ligação ao GTP/imunologia , Glutamina/química , Glutens/imunologia , Humanos , Lisina/química , Proteômica , Transglutaminases/imunologia
19.
Pediatrics ; 144(4)2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31492765

RESUMO

BACKGROUND AND OBJECTIVES: Celiac disease (CeD) is associated with psychopathology in children. It is unknown whether this association is present in children with celiac disease autoimmunity (CDA) identified by screening. We examined the associations between subclinical CDA and emotional and behavioral problems in children without previous CeD diagnosis. METHODS: In a population-based cohort study of 3715 children (median age: 6 years), blood titers of tissue transglutaminase autoantibodies were analyzed. CDA was defined as a measurement of tissue transglutaminase autoantibodies ≥7 U/mL (n = 51). Children with previous CeD diagnosis or children on a gluten-free diet, were excluded. The Child Behavior Checklist (CBCL) was filled in by parents and was used to assess behavioral and emotional problems of children at a median age of 5.9 years. Multiple linear regression models were applied to evaluate the cross-sectional associations between CDA and CBCL scores. Sensitivity analyses were done in a subgroup of children who were seropositive carrying the HLA antigen risk alleles for CeD. RESULTS: In basic models, CDA was not associated with emotional and behavioral problems on the CBCL scales. After adjustment for confounders, CDA was significantly associated with anxiety problems (ß = .29; 95% confidence interval 0.02 to 0.55; P = .02). After exclusion of children who did not carry the HLA-DQ2 and/or HLA-DQ8 risk alleles (n = 4), CDA was additionally associated with oppositional defiant problems (ß = .35; 95% confidence interval 0.02 to 0.69). Associations were not explained by gastrointestinal complaints. CONCLUSIONS: Our results reveal that CDA, especially combined with the HLA-DQ2 and HLA-DQ8 risk alleles, is associated with anxiety problems and oppositional defiant problems. Further research should be used to establish whether behavioral problems are a reflection of subclinical CeD.


Assuntos
Ansiedade/imunologia , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/imunologia , Doenças Autoimunes/psicologia , Doença Celíaca/imunologia , Doença Celíaca/psicologia , Autoanticorpos/sangue , Doenças Autoimunes/sangue , Doenças Autoimunes/genética , Doença Celíaca/sangue , Doença Celíaca/diagnóstico , Lista de Checagem , Criança , Pré-Escolar , Intervalos de Confiança , Feminino , Proteínas de Ligação ao GTP/imunologia , Antígenos HLA-DQ/sangue , Antígenos HLA-DQ/genética , Humanos , Lactente , Modelos Lineares , Masculino , Comportamento Problema/psicologia , Estudos Prospectivos , Sensibilidade e Especificidade , Fatores Sexuais , Transglutaminases/imunologia
20.
ACS Sens ; 4(10): 2679-2687, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31497948

RESUMO

In this work, 1-200 µL polypropylene micropipette tips were used as platforms for performing immunoassays after converting their inner surfaces on a capture zone for the analyte of interest. We have used a micropipette-tip immunoelectroanalytical platform for the detection of antitissue transglutaminase (IgA), the main biomarker for celiac disease. Modification of the tip wall with poly-l-lysine allowed adsorption of tissue transglutaminase (tTG), which will capture later anti-tTG (IgA) antibodies developed in celiac-affected people. A sandwich-type format was followed, incubating simultaneously the analyte and the detection antibody, labeled with horseradish peroxidase. With this new application for an extremely common lab material, we can perform quantitative analysis by dispensing the liquid into a low-cost and miniaturized staple-based paper electrochemical platform. The analytical signal was the reduction of the enzymatically oxidized substrate, recorded chronoamperometrically (i-t curve). The intensity of the current obtained at a fixed time after the application of the cathodic potential followed a linear relationship with anti-tTG (IgA) concentration. The relative standard deviation obtained for immunoassays performed in different tips indicates the adequate precision of this new methodology, which is very promising for decentralized analysis. Negative and positive controls produced results that were in accordance with those obtained with spectrophotometric enzyme linked-immunosorbent assays.


Assuntos
Técnicas Eletroquímicas , Proteínas de Ligação ao GTP/análise , Imunoensaio , Transglutaminases/análise , Doença Celíaca/diagnóstico , Proteínas de Ligação ao GTP/química , Proteínas de Ligação ao GTP/imunologia , Peroxidase do Rábano Silvestre/química , Humanos , Imunoglobulina A/imunologia , Papel , Polilisina/química , Transglutaminases/química , Transglutaminases/imunologia
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