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1.
Genes (Basel) ; 12(6)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201206

RESUMO

Organ-specific autoimmune diseases, such as type 1 diabetes, are believed to result from T-cell-mediated damage of the target tissue. The immune-mediated tissue injury, in turn, is known to depend on complex interactions between genetic and environmental factors. Nevertheless, the mechanisms whereby environmental factors contribute to the pathogenesis of autoimmune diseases remain elusive and represent a major untapped target to develop novel strategies for disease prevention. Given the impact of the early environment on the developing immune system, epigenetic changes induced by maternal factors during fetal life have been linked to a likelihood of developing an autoimmune disease later in life. In humans, DNA methylation is the epigenetic mechanism most extensively investigated. This review provides an overview of the critical role of DNA methylation changes induced by prenatal maternal conditions contributing to the increased risk of immune-mediated diseases on the offspring, with a particular focus on T1D. A deeper understanding of epigenetic alterations induced by environmental stressors during fetal life may be pivotal for developing targeted prevention strategies of type 1 diabetes by modifying the maternal environment.


Assuntos
Diabetes Mellitus Tipo 1/genética , Desenvolvimento Fetal/genética , Impressão Genômica , Herança Materna , Animais , Metilação de DNA , Diabetes Mellitus Tipo 1/imunologia , Humanos
2.
Microorganisms ; 8(11)2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33171580

RESUMO

While human enteroviruses are generally regarded as a lytic virus, and persistent non-cytolytic enterovirus infection in pancreatic beta cells has been suspected of playing a role in type 1 diabetes pathogenesis. However, it is still unclear how enteroviruses could exit the pancreatic beta cell in a non-lytic manner. This study aimed to investigate the role of beta cell-derived extracellular vesicles (EVs) in the non-lytic enteroviral spread and infection. Size-exclusion chromatography and antibody-based immunoaffinity purification were used to isolate EVs from echovirus 16-infected human beta EndoC-ßH1 cells. EVs were then characterized using transmission electron microscopy and Multiplex Bead-Based Flow Cytometry Assay. Virus production and release were quantified by 50% cell culture infectious dose (CCID50) assay and qRT-PCR. Our results showed that EVs from echovirus 16-infected EndoC-ßH1 cells harbor infectious viruses and promote their spread during the pre-lytic phase of infection. Furthermore, the EVs-mediated infection was not inhibited by virus-specific neutralizing antibodies. In summary, this study demonstrated that enteroviruses could exit beta cells non-lytically within infectious EVs, thereby thwarting the access of neutralizing antibodies to viral particles. These data suggest that enterovirus transmission through EVs may contribute to viral dissemination and immune evasion in persistently infected beta cells.

4.
Diabetologia ; 63(11): 2372-2384, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32676816

RESUMO

AIM/HYPOTHESIS: Human enteroviral infections are suggested to be associated with type 1 diabetes. However, the mechanism by which enteroviruses can trigger disease remains unknown. The present study aims to investigate the impact of enterovirus on autophagy, a cellular process that regulates beta cell homeostasis, using the clonal beta cell line INS(832/13) and human islet cells as in vitro models. METHODS: INS(832/13) cells and human islet cells were infected with a strain of echovirus 16 (E16), originally isolated from the stool of a child who developed type 1 diabetes-associated autoantibodies. Virus production and release was determined by 50% cell culture infectious dose (CCID50) assay and FACS analysis. The occurrence of autophagy, autophagosomes, lysosomes and autolysosomes was detected by western blot, baculoviral-mediated expression of microtubule-associated protein light chain 3 (LC3)II-GFP and LysoTracker Red, and quantified by Cellomics ArrayScan. Autophagy was also monitored with a Cyto-ID detection kit. Nutrient deprivation (low glucose [2.8 mmol/l]), amino acid starvation (Earle's Balanced Salt Solution [EBSS]) and autophagy-modifying agents (rapamycin and chloroquine) were used in control experiments. Insulin secretion and the expression of autophagy-related (Atg) genes and genes involved in autophagosome-lysosome fusion were determined. RESULTS: E16-infected INS(832/13) cells displayed an accumulation of autophagosomes, compared with non-treated (NT) cells (grown in complete RPMI1640 containing 11.1 mmol/l glucose) (32.1 ± 1.7 vs 21.0 ± 1.2 µm2/cell; p = 0.05). This was accompanied by increased LC3II ratio both in E16-infected cells grown in low glucose (LG) (2.8 mmol/l) (0.42 ± 0.03 vs 0.11 ± 0.04 (arbitrary units [a.u.]); p < 0.0001) and grown in media containing 11.1 mmol/l glucose (0.37 ± 0.016 vs 0.05 ± 0.02 (a.u.); p < 0.0001). Additionally, p62 accumulated in cells after E16 infection when grown in LG (1.23 ± 0.31 vs 0.36 ± 0.12 (a.u.); p = 0.012) and grown in media containing 11.1 mmol/l glucose (1.79 ± 0.39 vs 0.66 ± 0.15 (a.u.); p = 0.0078). mRNA levels of genes involved in autophagosome formation and autophagosome-lysosome fusion remained unchanged in E16-infected cells, except Atg7, which was significantly increased when autophagy was induced by E16 infection, in combination with LG (1.48 ± 0.08-fold; p = 0.02) and at 11.1 mmol/l glucose (1.26 ± 0.2-fold; p = 0.001), compared with NT controls. Moreover, autophagosomes accumulated in E16-infected cells to the same extent as when cells were treated with the lysosomal inhibitor, chloroquine, clearly indicating that autophagosome turnover was blocked. Upon infection, there was an increased viral titre in the cell culture supernatant and a marked reduction in glucose-stimulated insulin secretion (112.9 ± 24.4 vs 209.8 ± 24.4 ng [mg protein]-1 h-1; p = 0.006), compared with uninfected controls, but cellular viability remained unaffected. Importantly, and in agreement with the observations for INS(832/13) cells, E16 infection impaired autophagic flux in primary human islet cells (46.5 ± 1.6 vs 34.4 ± 2.1 µm2/cell; p = 0.01). CONCLUSIONS/INTERPRETATION: Enteroviruses disrupt beta cell autophagy by impairing the later stages of the autophagic pathway, without influencing expression of key genes involved in core autophagy machinery. This results in increased viral replication, non-lytic viral spread and accumulation of autophagic structures, all of which may contribute to beta cell demise and type 1 diabetes. Graphical abstract.


Assuntos
Autofagia/fisiologia , Ilhotas Pancreáticas/metabolismo , Pâncreas/fisiologia , Autofagia/genética , Western Blotting , Feminino , Humanos , Masculino , Replicação Viral/genética , Replicação Viral/fisiologia
5.
Sci Rep ; 9(1): 9074, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235823

RESUMO

Maf transcription factors are critical regulators of beta-cell function. We have previously shown that reduced MafA expression in human and mouse islets is associated with a pro-inflammatory gene signature. Here, we investigate if the loss of Maf transcription factors induced autoimmune processes in the pancreas. Transcriptomics analysis showed expression of pro-inflammatory as well as immune cell marker genes. However, clusters of CD4+ T and B220+ B cells were associated primarily with adult MafA-/-MafB+/-, but not MafA-/- islets. MafA expression was detected in the thymus, lymph nodes and bone marrow suggesting a novel role of MafA in regulating immune-cell function. Analysis of pancreatic lymph node cells showed activation of CD4+ T cells, but lack of CD8+ T cell activation which also coincided with an enrichment of naïve CD8+ T cells. Further analysis of T cell marker genes revealed a reduction of T cell receptor signaling gene expression in CD8, but not in CD4+ T cells, which was accompanied with a defect in early T cell receptor signaling in mutant CD8+ T cells. These results suggest that loss of MafA impairs both beta- and T cell function affecting the balance of peripheral immune responses against islet autoantigens, resulting in local inflammation in pancreatic islets.


Assuntos
Regulação da Expressão Gênica , Ilhotas Pancreáticas/patologia , Fatores de Transcrição Maf Maior/metabolismo , Fator de Transcrição MafB/metabolismo , Animais , Células Apresentadoras de Antígenos/metabolismo , Autoimunidade , Linfócitos B/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Técnicas de Inativação de Genes , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Ilhotas Pancreáticas/imunologia , Fatores de Transcrição Maf Maior/deficiência , Fatores de Transcrição Maf Maior/genética , Fator de Transcrição MafB/deficiência , Fator de Transcrição MafB/genética , Camundongos , Mutação , Receptores de Antígenos de Linfócitos T/metabolismo , Transdução de Sinais
6.
Scand J Immunol ; 90(2): e12776, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31069824

RESUMO

The number of the X chromosome-linked genes has been previously suggested to influence immune responses and the development of autoimmune diseases. In the present study, we aimed at evaluating the level of expression of CD40L (an X-linked gene involved in adaptive immunity) and TLR7 (an X-linked gene involved in innate immunity) in a variety of different karyotypes. Those included males, females and patients with X chromosome aneuploidy. Healthy females (46, XX; n = 10) and healthy males (46, XY; n = 10) were compared to females with Turner syndrome (TS) (45, X; n = 11) and males with Klinefelter syndrome (KS) (47, XXY; n = 5). Stimulation of peripheral blood mononuclear cells (PBMCs) with PMA and ionomycin resulted in higher percentage of CD3 + CD40L+ T cells (P < 0.001) and higher level expression of CD40L in T cell (P < 0.001) in female and KS patients compared with male and TS patients. TLR7-mediated IFN-alpha production by HLADR + CD3- CD19- cells was significantly upregulated in healthy women compared with healthy males, TS and KS patients (P < 0.001). TLR7 agonist-stimulated PBMCs from healthy females and KS patients expressed significantly higher levels of TLR7 mRNA than those from male and TS patients (P < 0.05). The increased expression of the X-linked genes TLR7 and CD40L in healthy females and KS patients suggests that the presence of two X chromosomes plays a major role in enhancing both innate and adaptive immune responses. These results may contribute to the explanation of sex-based differences in immune biology and the sex bias in predisposition to autoimmune diseases.


Assuntos
Imunidade Adaptativa/genética , Ligante de CD40/biossíntese , Ligante de CD40/genética , Cromossomos Humanos X/genética , Dosagem de Genes/genética , Imunidade Inata/genética , Receptor 7 Toll-Like/biossíntese , Receptor 7 Toll-Like/genética , Imunidade Adaptativa/imunologia , Antígenos CD19/biossíntese , Complexo CD3/biossíntese , Células Cultivadas , Variações do Número de Cópias de DNA/genética , Feminino , Humanos , Imunidade Inata/imunologia , Interferon-alfa/biossíntese , Ionomicina/farmacologia , Síndrome de Klinefelter/genética , Leucócitos Mononucleares/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Masculino , Ácidos Polimetacrílicos/farmacologia , RNA Mensageiro/biossíntese , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Síndrome de Turner/genética
7.
Genes (Basel) ; 9(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567413

RESUMO

Type 1 (T1D) and type 2 (T2D) diabetes are triggered by a combination of environmental and/or genetic factors. Maf transcription factors regulate pancreatic beta (ß)-cell function, and have also been implicated in the regulation of immunomodulatory cytokines like interferon-ß (IFNß1). In this study, we assessed MAFA and MAFB co-expression with pro-inflammatory cytokine signaling genes in RNA-seq data from human pancreatic islets. Interestingly, MAFA expression was strongly negatively correlated with cytokine-induced signaling (such as IFNAR1, DDX58) and T1D susceptibility genes (IFIH1), whereas correlation of these genes with MAFB was weaker. In order to evaluate if the loss of MafA altered the immune status of islets, MafA deficient mouse islets (MafA-/-) were assessed for inherent anti-viral response and susceptibility to enterovirus infection. MafA deficient mouse islets had elevated basal levels of Ifnß1, Rig1 (DDX58 in humans), and Mda5 (IFIH1) which resulted in reduced virus propagation in response to coxsackievirus B3 (CVB3) infection. Moreover, an acute knockdown of MafA in ß-cell lines also enhanced Rig1 and Mda5 protein levels. Our results suggest that precise regulation of MAFA levels is critical for islet cell-specific cytokine production, which is a critical parameter for the inflammatory status of pancreatic islets.

8.
Viruses ; 9(2)2017 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-28146100

RESUMO

Human enteroviruses (HEV), especially coxsackievirus serotype B (CVB) and echovirus (E), have been associated with diseases of both the exocrine and endocrine pancreas, but so far evidence on HEV infection in human pancreas has been reported only in islets and ductal cells. This study aimed to investigate the capability of echovirus strains to infect human exocrine and endocrine pancreatic cells. Infection of explanted human islets and exocrine cells with seven field strains of E6 caused cytopathic effect, virus titer increase and production of HEV protein VP1 in both cell types. Virus particles were found in islets and acinar cells infected with E6. No cytopathic effect or infectious progeny production was observed in exocrine cells exposed to the beta cell-tropic strains of E16 and E30. Endocrine cells responded to E6, E16 and E30 by upregulating the transcription of interferon-induced with helicase C domain 1 (IF1H1), 2'-5'-oligoadenylate synthetase 1 (OAS1), interferon-ß (IFN-ß), chemokine (C-X-C motif) ligand 10 (CXCL10) and chemokine (C-C motif) ligand 5 (CCL5). Echovirus 6, but not E16 or E30, led to increased transcription of these genes in exocrine cells. These data demonstrate for the first time that human exocrine cells represent a target for E6 infection and suggest that certain HEV serotypes can replicate in human pancreatic exocrine cells, while the pancreatic endocrine cells are permissive to a wider range of HEV.


Assuntos
Echovirus 6 Humano/imunologia , Imunidade Inata , Ilhotas Pancreáticas/imunologia , Ilhotas Pancreáticas/virologia , Pâncreas Exócrino/imunologia , Pâncreas Exócrino/virologia , Efeito Citopatogênico Viral , Perfilação da Expressão Gênica , Humanos , Fatores Imunológicos/biossíntese , Técnicas de Cultura de Órgãos , Carga Viral , Proteínas Estruturais Virais/análise
9.
Nat Commun ; 7: 13555, 2016 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-27898055

RESUMO

The incidence of type 1 diabetes (T1D) has substantially increased over the past decade, suggesting a role for non-genetic factors such as epigenetic mechanisms in disease development. Here we present an epigenome-wide association study across 406,365 CpGs in 52 monozygotic twin pairs discordant for T1D in three immune effector cell types. We observe a substantial enrichment of differentially variable CpG positions (DVPs) in T1D twins when compared with their healthy co-twins and when compared with healthy, unrelated individuals. These T1D-associated DVPs are found to be temporally stable and enriched at gene regulatory elements. Integration with cell type-specific gene regulatory circuits highlight pathways involved in immune cell metabolism and the cell cycle, including mTOR signalling. Evidence from cord blood of newborns who progress to overt T1D suggests that the DVPs likely emerge after birth. Our findings, based on 772 methylomes, implicate epigenetic changes that could contribute to disease pathogenesis in T1D.


Assuntos
Metilação de DNA/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Ilhas de CpG/genética , Sangue Fetal/metabolismo , Humanos , Anotação de Sequência Molecular , Fatores de Tempo , Gêmeos Monozigóticos/genética
10.
Mol Cell Endocrinol ; 430: 138-45, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-26845344

RESUMO

The intronic SNP rs7903146 in the T-cell factor 7-like 2 gene (TCF7L2) is the common genetic variant most highly associated with Type 2 diabetes known to date. The risk T-allele is located in an open chromatin region specific to human pancreatic islets of Langerhans, thereby accessible for binding of regulatory proteins. The risk T-allele locus exhibits stronger enhancer activity compared to the non-risk C-allele. The aim of this study was to identify transcriptional regulators that bind the open chromatin region in the rs7903146 locus and thereby potentially regulate TCF7L2 expression and activity. Using affinity chromatography followed by Edman sequencing, we identified one candidate regulatory protein, i.e. high-mobility group protein B1 (HMGB1). The binding of HMGB1 to the rs7903146 locus was confirmed in pancreatic islets from human deceased donors, in HCT116 and in HEK293 cell lines using: (i) protein purification on affinity columns followed by Western blot, (ii) chromatin immunoprecipitation followed by qPCR and (iii) electrophoretic mobility shift assay. The results also suggested that HMGB1 might have higher binding affinity to the C-allele of rs7903146 compared to the T-allele, which was supported in vitro using Dynamic Light Scattering, possibly in a tissue-specific manner. The functional consequence of HMGB1 depletion in HCT116 and INS1 cells was reduced insulin and TCF7L2 mRNA expression, TCF7L2 transcriptional activity and glucose stimulated insulin secretion. These findings suggest that the rs7903146 locus might exert its enhancer function by interacting with HMGB1 in an allele dependent manner.


Assuntos
Loci Gênicos , Proteína HMGB1/metabolismo , Ilhotas Pancreáticas/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Proteína 2 Semelhante ao Fator 7 de Transcrição/genética , Animais , Simulação por Computador , DNA/metabolismo , Difusão Dinâmica da Luz , Células HCT116 , Células HEK293 , Humanos , Hidrodinâmica , Ligação Proteica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Reprodutibilidade dos Testes
11.
J Med Virol ; 88(6): 971-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26629879

RESUMO

In an earlier study, infection of human pancreatic islets with epidemic strains of echovirus (E4, E16, E30), with proven but differently ability to induce islet autoimmunity, resulted either in a severe damage (i.e., E16 and E30) or proceeded without visible changes in infected islets (i.e., E4). In this study, the ability of these strains to replicate in beta cells and the consequence of such an infection for beta cell lysis and beta cell function was studied in the pancreatic beta cell lines INS-1, MIN6, and NIT-1. The strains of E16 and E30 did replicate in INS1, MIN6, and NIT1 cells and resulted in a pronounced cytopathic effect within 3 days following infection. By contrast, E4 replicated in all examined insulinoma cells with no apparent cell destruction. The insulin release in response to high glucose stimulation was hampered in all infected cells (P < 0.05) when no evidence of cytolysis was present; however, the adverse effect of E16 and E30 on insulin secretion appeared to be higher than that of the E4 strain. The differential effects of echovirus infection on cell lysis, and beta cell function in the rodent insulinoma INS1, MIN6, and NIT 1 cells reflect those previously obtained in primary human islets and support the notion that the insulin-producing beta cells can harbor a non-cytopathic viral infection.


Assuntos
Efeito Citopatogênico Viral , Enterovirus Humano B/fisiologia , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/virologia , Insulina/metabolismo , Replicação Viral , Morte Celular , Linhagem Celular , Enterovirus Humano B/patogenicidade , Glucose/farmacologia , Humanos , Secreção de Insulina , Células Secretoras de Insulina/patologia , Insulinoma
12.
Proc Natl Acad Sci U S A ; 111(38): 13924-9, 2014 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-25201977

RESUMO

Genetic variation can modulate gene expression, and thereby phenotypic variation and susceptibility to complex diseases such as type 2 diabetes (T2D). Here we harnessed the potential of DNA and RNA sequencing in human pancreatic islets from 89 deceased donors to identify genes of potential importance in the pathogenesis of T2D. We present a catalog of genetic variants regulating gene expression (eQTL) and exon use (sQTL), including many long noncoding RNAs, which are enriched in known T2D-associated loci. Of 35 eQTL genes, whose expression differed between normoglycemic and hyperglycemic individuals, siRNA of tetraspanin 33 (TSPAN33), 5'-nucleotidase, ecto (NT5E), transmembrane emp24 protein transport domain containing 6 (TMED6), and p21 protein activated kinase 7 (PAK7) in INS1 cells resulted in reduced glucose-stimulated insulin secretion. In addition, we provide a genome-wide catalog of allelic expression imbalance, which is also enriched in known T2D-associated loci. Notably, allelic imbalance in paternally expressed gene 3 (PEG3) was associated with its promoter methylation and T2D status. Finally, RNA editing events were less common in islets than previously suggested in other tissues. Taken together, this study provides new insights into the complexity of gene regulation in human pancreatic islets and better understanding of how genetic variation can influence glucose metabolism.


Assuntos
Genômica , Glucose , Transcriptoma/fisiologia , 5'-Nucleotidase/biossíntese , 5'-Nucleotidase/genética , Linhagem Celular , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Feminino , Proteínas Ligadas por GPI/biossíntese , Proteínas Ligadas por GPI/genética , Glucose/genética , Glucose/metabolismo , Humanos , Ilhotas Pancreáticas , Masculino , Edição de RNA/fisiologia , RNA Longo não Codificante/biossíntese , RNA Longo não Codificante/genética , Tetraspaninas/biossíntese , Tetraspaninas/genética , Proteínas de Transporte Vesicular/biossíntese , Proteínas de Transporte Vesicular/genética , Quinases Ativadas por p21/biossíntese , Quinases Ativadas por p21/genética
13.
Stem Cells ; 32(5): 1110-23, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24302539

RESUMO

The identity of the cells that contribute to brain tumor structure and progression remains unclear. Mesenchymal stem cells (MSCs) have recently been isolated from normal mouse brain. Here, we report the infiltration of MSC-like cells into the GL261 murine glioma model. These brain tumor-derived mesenchymal stem cells (BT-MSCs) are defined with the phenotype (Lin-Sca-1+CD9+CD44+CD166+/-) and have multipotent differentiation capacity. We show that the infiltration of BT-MSCs correlates to tumor progression; furthermore, BT-MSCs increased the proliferation rate of GL261 cells in vitro. For the first time, we report that the majority of GL261 cells expressed mesenchymal phenotype under both adherent and sphere culture conditions in vitro and that the non-MSC population is nontumorigenic in vivo. Although the GL261 cell line expressed mesenchymal phenotype markers in vitro, most BT-MSCs are recruited cells from host origin in both wild-type GL261 inoculated into green fluorescent protein (GFP)-transgenic mice and GL261-GFP cells inoculated into wild-type mice. We show the expression of chemokine receptors CXCR4 and CXCR6 on different recruited cell populations. In vivo, the GL261 cells change marker profile and acquire a phenotype that is more similar to cells growing in sphere culture conditions. Finally, we identify a BT-MSC population in human glioblastoma that is CD44+CD9+CD166+ both in freshly isolated and culture-expanded cells. Our data indicate that cells with MSC-like phenotype infiltrate into the tumor stroma and play an important role in tumor cell growth in vitro and in vivo. Thus, we suggest that targeting BT-MSCs could be a possible strategy for treating glioblastoma patients.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Glioma/patologia , Células-Tronco Mesenquimais/patologia , Molécula de Adesão de Leucócito Ativado/metabolismo , Animais , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Células Cultivadas , Progressão da Doença , Citometria de Fluxo , Glioma/genética , Glioma/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Receptores de Hialuronatos/metabolismo , Imunofenotipagem , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Transgênicos , Microscopia Confocal , Células-Tronco Multipotentes/metabolismo , Células-Tronco Multipotentes/patologia , Receptores CXCR/metabolismo , Receptores CXCR4/metabolismo , Receptores CXCR6 , Análise de Sobrevida , Tetraspanina 29/metabolismo
14.
PLoS One ; 8(11): e77850, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24223733

RESUMO

Three large-scale Echovirus (E) epidemics (E4,E16,E30), each differently associated to the acute development of diabetes related autoantibodies, have been documented in Cuba. The prevalence of islet cell autoantibodies was moderate during the E4 epidemic but high in the E16 and E30 epidemic. The aim of this study was to evaluate the effect of epidemic strains of echovirus on beta-cell lysis, beta-cell function and innate immunity gene expression in primary human pancreatic islets. Human islets from non-diabetic donors (n = 7) were infected with the virus strains E4, E16 and E30, all isolated from patients with aseptic meningitis who seroconverted to islet cell antibody positivity. Viral replication, degree of cytolysis, insulin release in response to high glucose as well as mRNA expression of innate immunity genes (IFN-b, RANTES, RIG-I, MDA5, TLR3 and OAS) were measured. The strains of E16 and E30 did replicate well in all islets examined, resulting in marked cytotoxic effects. E4 did not cause any effects on cell lysis, however it was able to replicate in 2 out of 7 islet donors. Beta-cell function was hampered in all infected islets (P<0.05); however the effect of E16 and E30 on insulin secretion appeared to be higher than the strain of E4. TLR3 and IFN-beta mRNA expression increased significantly following infection with E16 and E30 (P<0.033 and P<0.039 respectively). In contrast, the expression of none of the innate immunity genes studied was altered in E4-infected islets. These findings suggest that the extent of the epidemic-associated islet autoimmunity may depend on the ability of the viral strains to damage islet cells and induce pro-inflammatory innate immune responses within the infected islets.


Assuntos
Enterovirus Humano B/imunologia , Expressão Gênica/imunologia , Imunidade Inata/genética , Ilhotas Pancreáticas/imunologia , Células Cultivadas , Infecções por Echovirus/imunologia , Infecções por Echovirus/virologia , Enterovirus Humano B/genética , Epidemias , Genes Virais , Interações Hospedeiro-Patógeno , Humanos , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/virologia , Filogenia
15.
Clin Transl Allergy ; 3: 19, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23799882

RESUMO

INTRODUCTION: An association between pollen count (Poaceae) and symptoms is well known, but to a lesser degree the importance of priming and lag effects. Also, threshold levels for changes in symptom severity need to be validated. The present study aims to investigate the relationship between pollen counts, symptoms and health related quality of life (HRQL), and to validate thresholds levels, useful in public pollen warnings. MATERIAL AND METHODS: Children aged 7-18 with grass pollen allergy filled out a symptom diary during the pollen season for nose, eyes and lung symptoms, as well as a HRQL questionnaire every week. Pollen counts were monitored using a volumetric spore trap. RESULTS: 89 (91%) of the included 98 children completed the study. There was a clear association between pollen count, symptom severity and HRQL during the whole pollen season, but no difference in this respect between early and late pollen season. There was a lag effect of 1-3 days after pollen exposure except for lung symptoms. We found only two threshold levels, at 30 and 80 pollen grains/m(3) for the total symptom score, not three as is used today. The nose and eyes reacted to low doses, but for the lung symptoms, symptom strength did hardly change until 50 pollen grains/m(3). CONCLUSION: Grass pollen has an effect on symptoms and HRQL, lasting up to 5 days after exposure. Symptoms from the lungs appear to have higher threshold levels than the eyes and the nose. Overall symptom severity does not appear to change during the course of season. Threshold levels need to be revised. We suggest a traffic light model for public pollen warnings directed to children, where green signifies "no problem", yellow signifies "can be problems, especially if you are highly sensitive" and red signifies "alert - take action".

16.
Diabetes Metab Res Rev ; 29(7): 557-67, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23674484

RESUMO

BACKGROUND: The vast array and quantity of longitudinal samples collected in The Environmental Determinants of Diabetes in the Young study present a series of challenges in terms of quality control procedures and data validity. To address this, pilot studies have been conducted to standardize and enhance both biospecimen collection and sample obtainment in terms of autoantibody collection, stool sample preservation, RNA, biomarker stability, metabolic biomarkers and T-cell viability. RESEARCH DESIGN AND METHODS: The Environmental Determinants of Diabetes in the Young is a multicentre, international prospective study (n = 8677) designed to identify environmental triggers of type 1 diabetes (T1D) in genetically at-risk children from ages 3 months until 15 years. The study is conducted through six primary clinical centres located in four countries. RESULTS: As of May 2012, over three million biological samples and 250 million total data points have been collected, which will be analysed to assess autoimmunity status, presence of inflammatory biomarkers, genetic factors, exposure to infectious agents, dietary biomarkers and other potentially important environmental exposures in relation to autoimmunity and progression to T1D. CONCLUSIONS: Detailed procedures were utilized to standardize both data harmonization and management when handling a large quantity of longitudinal samples obtained from multiple locations. In addition, a description of the available specimens is provided that serve as an invaluable repository for the elucidation of determinants in T1D focusing on autoantibody concordance and harmonization, transglutaminase autoantibody, inflammatory biomarkers (T-cells), genetic proficiency testing, RNA lab internal quality control testing, infectious agents (monitoring cross-contamination, virus preservation and nasal swab collection validity) and HbA1c testing.


Assuntos
Bancos de Espécimes Biológicos/organização & administração , Bancos de Espécimes Biológicos/normas , Diabetes Mellitus Tipo 1/patologia , Manejo de Espécimes/métodos , Manejo de Espécimes/normas , Adolescente , Autoanticorpos/sangue , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/genética , Fezes/virologia , Humanos , Lactente , Recém-Nascido , Estudos Longitudinais , Controle de Qualidade , RNA Mensageiro/análise
17.
Pediatr Diabetes ; 14(5): 341-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23469940

RESUMO

AIMS: Children with type 1 diabetes (T1D) risk and islet autoantibodies are recruited to a secondary prevention study. The aims were to determine metabolic control in relation to human leukocyte antigen (HLA) genetic risk and islet autoantibodies in prepubertal children. METHODS: In 47 healthy children with GADA and at least one additional islet autoantibody, intravenous glucose tolerance test (IvGTT) and oral glucose tolerance test (OGTT) were performed 8-65 d apart. Hemoglobin A1c, plasma glucose as well as serum insulin and C-peptide were determined at fasting and during IvGTT and OGTT. RESULTS: All children aged median 5.1 (4.0-9.2) yr had autoantibodies to two to six of the beta-cell antigens GAD65, insulin, IA-2, and the three amino acid position 325 variants of the ZnT8 transporter. In total, 20/47 children showed impaired glucose metabolism. Decreased (≤ 30 µU/mL insulin) first-phase insulin response (FPIR) was found in 14/20 children while 11/20 had impaired glucose tolerance in the OGTT. Five children had both impaired glucose tolerance and FPIR ≤ 30 µU/mL insulin. Number and levels of autoantibodies were not associated with glucose metabolism, except for an increased frequency (p = 0.03) and level (p = 0.01) of ZnT8QA in children with impaired glucose metabolism. Among the children with impaired glucose metabolism, 13/20 had HLA-DQ2/8, compared to 9/27 of the children with normal glucose metabolism (p = 0.03). CONCLUSION: Secondary prevention studies in children with islet autoantibodies are complicated by variability in baseline glucose metabolism. Evaluation of metabolic control with both IvGTT and OGTT is critical and should be taken into account before randomization. All currently available autoantibody tests should be analyzed, including ZnT8QA.


Assuntos
Autoanticorpos/sangue , Diabetes Mellitus Tipo 1/prevenção & controle , Intolerância à Glucose/imunologia , Glutamato Descarboxilase/imunologia , Células Secretoras de Insulina/imunologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/imunologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/imunologia , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Antígenos HLA/imunologia , Antígenos HLA-DQ/imunologia , Humanos , Insulina/imunologia , Masculino , Proteínas Tirosina Fosfatases Classe 8 Semelhantes a Receptores/imunologia , Transportador 8 de Zinco
18.
Diabetes ; 62(7): 2481-91, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23396400

RESUMO

Type 1 diabetes is characterized by autoimmune destruction of pancreatic ß-cells in genetically susceptible individuals. Triggers of islet autoimmunity, time course, and the precise mechanisms responsible for the progressive ß-cell failure are not completely understood. The recent escalation of obesity in affluent countries has been suggested to contribute to the increased incidence of type 1 diabetes. Understanding the link between metabolism and immune tolerance could lead to the identification of new markers for the monitoring of disease onset and progression. We studied several immune cell subsets and factors with high metabolic impact as markers associated with disease progression in high-risk subjects and type 1 diabetic patients at onset and at 12 and 24 months after diagnosis. A multiple correlation matrix among different parameters was evaluated statistically and assessed visually on two-dimensional graphs. Markers to predict residual ß-cell function up to 1 year after diagnosis were identified in multivariate logistic regression models. The meta-immunological profile changed significantly over time in patients, and a specific signature that was associated with worsening disease was identified. A multivariate logistic regression model measuring age, BMI, fasting C-peptide, number of circulating CD3(+)CD16(+)CD56(+) cells, and the percentage of CD1c(+)CD19(-)CD14(-)CD303(-) type 1 myeloid dendritic cells at disease onset had a significant predictive value. The identification of a specific meta-immunological profile associated with disease status may contribute to our understanding of the basis of diabetes progression.


Assuntos
Autoimunidade/imunologia , Diabetes Mellitus Tipo 1/imunologia , Monitorização Imunológica/métodos , Linfócitos T/imunologia , Biomarcadores , Criança , Progressão da Doença , Citometria de Fluxo , Humanos , Células Secretoras de Insulina/imunologia , Prognóstico
19.
Clin Respir J ; 7(2): 168-75, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22621438

RESUMO

INTRODUCTION: Respiratory allergic disorders like rhinitis and asthma are common conditions that not only affect target organs, but complicate the daily life of affected children and adolescents. OBJECTIVES: The aim of this study was to investigate the QoL (quality of life) in children with grass pollen allergy in and out of grass pollen season. METHODS: We used the Pediatric Allergic Disease Quality of Life Questionnaire (PADQLQ), a disease-specific questionnaire including both asthma and rhinitis symptoms. We also used the DISABKIDS (a European project which aims at enhancing the quality of life and the independence of children with chronic health conditions and their families) questionnaire, a generic questionnaire covering non-organ-specific effects of disease. RESULTS: Ninety-eight children 7­18 years old with grass pollen allergy were included. Eighty-nine children (91%) completed the study. The QoL was significantly decreased during pollen season assessed both with DISABKIDS and PADQLQ. The correlation between the questionnaires was 0.73. Not only the physical domain score (P = 0.00093) but also the emotional domain score (P = 0.034) was significantly lowered. Children with multiple manifestations (asthma and rhinitis) had lower QoL than children with rhinitis alone (P = 0.01). Multiple regression analysis showed a highly significant impact on QoL for symptoms from nose, eyes and lungs. They were equally important (standardized coefficient 047, 0.47 and 0.46, respectively). CONCLUSION: The QoL in children and adolescents with respiratory allergy deteriorates during pollen season. This was shown both with generic (DISABKIDS) and disease-specific instrument (PADQLQ).


Assuntos
Asma/fisiopatologia , Rinite Alérgica Sazonal/fisiopatologia , Adolescente , Alérgenos/imunologia , Asma/diagnóstico , Asma/psicologia , Criança , Feminino , Humanos , Masculino , Qualidade de Vida , Rinite Alérgica Sazonal/diagnóstico , Rinite Alérgica Sazonal/psicologia , Inquéritos e Questionários , Suécia
20.
Genome Res ; 22(11): 2138-45, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22919074

RESUMO

A major concern in common disease epigenomics is distinguishing causal from consequential epigenetic variation. One means of addressing this issue is to identify the temporal origins of epigenetic variants via longitudinal analyses. However, prospective birth-cohort studies are expensive and time consuming. Here, we report DNA methylomics of archived Guthrie cards for the retrospective longitudinal analyses of in-utero-derived DNA methylation variation. We first validate two methodologies for generating comprehensive DNA methylomes from Guthrie cards. Then, using an integrated epigenomic/genomic analysis of Guthrie cards and follow-up samplings, we identify interindividual DNA methylation variation that is present both at birth and 3 yr later. These findings suggest that disease-relevant epigenetic variation could be detected at birth, i.e., before overt clinical disease. Guthrie card methylomics offers a potentially powerful and cost-effective strategy for studying the dynamics of interindividual epigenomic variation in a range of common human diseases.


Assuntos
Alelos , Metilação de DNA , Epigênese Genética , Feminino , Loci Gênicos , Variação Genética , Genoma Humano , Testes Hematológicos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Recém-Nascido , Estudos Longitudinais , Masculino , Análise de Sequência de DNA
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