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1.
Intern Med J ; 52(12): 2046-2067, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36478370

RESUMO

Amyloidosis is a collection of diseases caused by the misfolding of proteins that aggregate into insoluble amyloid fibrils and deposit in tissues. While these fibrils may aggregate to form insignificant localised deposits, they can also accumulate in multiple organs to the extent that amyloidosis can be an immediately life-threatening disease, requiring urgent treatment. Recent advances in diagnostic techniques and therapies are dramatically changing the disease landscape and patient prognosis. Delays in diagnosis and treatment remain the greatest challenge, necessitating physician awareness of the common clinical presentations that suggest amyloidosis. The most common types are transthyretin (ATTR) amyloidosis followed by immunoglobulin light-chain (AL) amyloidosis. While systemic AL amyloidosis was previously considered a death sentence with no effective therapies, significant improvement in patient survival has occurred over the past 2 decades, driven by greater understanding of the disease process, risk-adapted adoption of myeloma therapies such as proteosome inhibitors (bortezomib) and monoclonal antibodies (daratumumab) and improved supportive care. ATTR amyloidosis is an underdiagnosed cause of heart failure. Technetium scintigraphy has made noninvasive diagnosis much easier, and ATTR is now recognised as the most common type of amyloidosis because of the increased identification of age-related ATTR. There are emerging ATTR treatments that slow disease progression, decrease patient hospitalisations and improve patient quality of life and survival. This review aims to update physicians on recent developments in amyloidosis diagnosis and management and to provide a diagnostic and treatment framework to improve the management of patients with all forms of amyloidosis.


Assuntos
Amiloidose , Cardiomiopatias , Insuficiência Cardíaca , Humanos , Qualidade de Vida , Amiloidose/diagnóstico , Amiloidose/terapia , Amiloidose/complicações , Insuficiência Cardíaca/diagnóstico , Prognóstico , Bortezomib/uso terapêutico , Cardiomiopatias/diagnóstico
2.
Genes Immun ; 22(4): 227-233, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34163021

RESUMO

Although genetic and epidemiological evidence indicates vitamin D insufficiency contributes to multiple sclerosis (MS), and serum levels of vitamin D increase on treatment with cholecalciferol, recent metanalyses indicate that this vitamin D form does not ameliorate disease. Genetic variation in genes regulating vitamin D, and regulated by vitamin D, affect MS risk. We evaluated if the expression of vitamin D responsive MS risk genes could be used to assess vitamin D response in immune cells. Peripheral blood mononuclear cells (PBMCs) were isolated from healthy controls and people with MS treated with dimethyl fumarate. We assayed changes in expression of vitamin D responsive MS risk (VDRMS) genes in response to treatment with 25 hydroxy vitamin D in the presence or absence of inflammatory stimuli. Expression of CYP24A1 and other VDRMS genes was significantly altered in PBMCs treated with vitamin D in the homeostatic and inflammatory models. Gene expression in MS samples had similar responses to controls, but lower initial expression of the risk genes. Vitamin D treatment abrogated these differences. Expression of CYP24A1 and other MS risk genes in blood immune cells indicate vitamin D response and could enable assessment of immunological response to vitamin D in clinical trials and on therapy.


Assuntos
Esclerose Múltipla , Humanos , Leucócitos Mononucleares , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/genética , Vitamina D , Vitamina D3 24-Hidroxilase/genética
3.
Hum Mol Genet ; 28(2): 269-278, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30285234

RESUMO

Epidemiological, molecular and genetic studies have indicated that high serum vitamin D levels are associated with lower risk of several autoimmune diseases. The vitamin D receptor (VDR) binding sites in monocytes and dendritic cells (DCs) are more common in risk genes for diseases with latitude dependence than in risk genes for other diseases. The transcription factor genes Zinc finger MIZ domain-containing protein 1 (ZMIZ1) and interferon regulatory factor 8 (IRF8)-risk genes for many of these diseases-have VDR binding peaks co-incident with the risk single nucleotide polymorphisms (SNPs). We show these genes are responsive to vitamin D: ZMIZ1 expression increased and IRF8 expression decreased, and this response was affected by genotype in different cell subsets. The IL10/IL12 ratio in tolerogenic DCs increased with vitamin D. These data indicate that vitamin D regulation of ZMIZ1 and IRF8 in DCs and monocytes contribute to latitude-dependent autoimmune disease risk.


Assuntos
Doenças Autoimunes/genética , Diferenciação Celular/genética , Fatores Reguladores de Interferon/genética , Monócitos/citologia , Fatores de Transcrição/genética , Vitamina D/farmacologia , Vitaminas/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Células Dendríticas/citologia , Geografia Médica , Humanos
4.
Genes Immun ; 21(5): 335-347, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33037402

RESUMO

Multiple lines of evidence indicate Multiple Sclerosis (MS) is affected by vitamin D. This effect may be mediated by methylation in immune cell progenitors. We aimed to determine (1) if haematopoietic stem cell methylation constrains methylation in daughter cells and is variable between individuals, and (2) the interaction of methylation with the vitamin D receptor binding sites. We interrogated genomic methylation levels from matching purified CD34+ haematopoietic stem cells and progeny CD14+ monocytes and CD56+ NK cells from 11 individuals using modified reduced representation bisulfite sequencing. Differential methylation of Vitamin D Receptor binding sites and MS risk genes was assessed from this and using pyrosequencing for the vitamin D regulated MS risk gene ZMIZ1. Although DNA methylation states at CpG islands and other sites are almost entirely recapitulated between progenitor and progeny immune cells, significant variation was detected at some regions between cell subsets and individuals; including around the MS risk genes HLA DRB1 and the vitamin D repressor NCOR2. Methylation of the vitamin D responsive MS risk gene ZMIZ1 was associated with risk SNP and disease. We conclude that DNA methylation settings in adult haematopoietic stem cells may contribute to individual variation in vitamin D responses in immune cells.


Assuntos
Metilação de DNA , Epigenoma , Células-Tronco Hematopoéticas/metabolismo , Esclerose Múltipla/genética , Vitamina D/metabolismo , Adulto , Ilhas de CpG , Feminino , Cadeias HLA-DRB1/genética , Hematopoese , Células-Tronco Hematopoéticas/citologia , Humanos , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/citologia , Monócitos/metabolismo , Esclerose Múltipla/metabolismo , Correpressor 2 de Receptor Nuclear/genética , Ligação Proteica , Receptores de Calcitriol/metabolismo , Fatores de Transcrição/genética
5.
Genes Immun ; 21(2): 91-99, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31619767

RESUMO

Epstein-Barr Virus (EBV) infection appears to be necessary for the development of Multiple Sclerosis (MS), although the specific mechanisms are unknown. More than 200 single-nucleotide polymorphisms (SNPs) are known to be associated with the risk of developing MS. About a quarter of these are also highly associated with proximal gene expression in B cells infected with EBV (lymphoblastoid cell lines-LCLs). The DNA of LCLs is hypomethylated compared with both uninfected and activated B cells. Since methylation can affect gene expression, and so cell differentiation and immune evasion, we hypothesised that EBV-driven hypomethylation may affect the interaction between EBV infection and MS. We interrogated an existing dataset comprising three individuals with whole-genome bisulfite sequencing data from EBV transformed B cells and CD40L-activated B cells. DNA methylation surrounding MS risk SNPs associated with gene expression in LCLs (LCLeQTL) was less likely to be hypomethylated than randomly selected chromosomal regions. Differential methylation was independent of genomic features such as promoter regions, but genes preferentially expressed in EBV-infected B cells, including the LCLeQTL genes, were underrepresented in the hypomethylated regions. Our data does not indicate MS genetic risk is affected by EBV hypomethylation.


Assuntos
Linfócitos B/metabolismo , Herpesvirus Humano 4/genética , Esclerose Múltipla/genética , Linfócitos B/fisiologia , Metilação de DNA/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/metabolismo , Humanos , Regiões Promotoras Genéticas/genética
6.
Heart Lung Circ ; 29(4): 575-583, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32001152

RESUMO

Amyloid cardiomyopathy is emerging as an important and under-recognised cause of heart failure and cardiac arrhythmias, especially in older adults. This disorder is characterised by extracellular deposition of amyloid fibrils that form due to misfolding of secreted light chains (AL) or transthyretin protein (ATTR). In ATTR, amyloid aggregates typically result from excessive accumulation of wild-type transthyretin (ATTRwt) or from protein structural defects caused by TTR gene variants (ATTRv). Amyloid fibril deposition may predominantly affect the heart or show multi-system involvement. Previously considered to be rare and inexorably progressive with no specific therapy, there has been enormous recent interest in ATTR cardiomyopathy due to upwardly-revised estimates of disease prevalence together with development of disease-modifying interventions. Because of this, there is a clinical imperative to have a high index of suspicion to identify potential cases and to be aware of contemporary diagnostic methods and treatment options. Genetic testing should be offered to all patients with proven ATTR to access the benefits of new therapies specific to ATTRv and allow predictive testing of family members. With heightened awareness of amyloid cardiomyopathy and expanded use of genetic testing, a substantial rise in the numbers of asymptomatic individuals who are carriers of pathogenic variants is expected, and optimal strategies for monitoring and treatment of these individuals at risk need to be determined. Pre-emptive administration of fibril-modifying therapies provides an unprecedented opportunity for disease prevention and promises to change amyloid cardiomyopathy from being a fatal to a treatable disorder.


Assuntos
Neuropatias Amiloides Familiares , Cardiomiopatias , Predisposição Genética para Doença , Testes Genéticos , Neuropatias Amiloides Familiares/complicações , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/terapia , Cardiomiopatias/etiologia , Cardiomiopatias/genética , Cardiomiopatias/terapia , Humanos , Pré-Albumina/genética
7.
Hum Mol Genet ; 23(6): 1425-34, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24158849

RESUMO

Genome-wide association studies have identified a linkage disequilibrium (LD) block on chromosome 12 associated with multiple sclerosis (MS), type 1 diabetes and other autoimmune diseases. This block contains CYP27B1, which catalyzes the conversion of 25 vitamin D3 (VitD3) to 1,25VitD3. Fine-mapping analysis has failed to identify which of the 17 genes in this block is most associated with MS. We have previously used a functional approach to identify the causal gene. We showed that the expression of several genes in this block in whole blood is highly associated with the MS risk allele, but not CYP27B1. Here, we show that CYP27B1 is predominantly expressed in dendritic cells (DCs). Its expression in these cells is necessary for their response to VitD, which is known to upregulate pathways involved in generating a tolerogenic DC phenotype. Here, we utilize a differentiation protocol to generate inflammatory (DC1) and tolerogenic (DC2) DCs, and show that for the MS risk allele CYP27B1 is underexpressed in DCs, especially DC2s. Of the other Chr12 LD block genes expressed in these cells, only METT21B expression was as affected by the genotype. Another gene associated with autoimmune diseases, CYP24A1, catabolizes 1,25 VitD3, and is predominantly expressed in DCs, but equally between DC1s and DC2s. Overall, these data are consistent with the hypothesis that reduced VitD pathway gene upregulation in DC2s of carriers of the risk haplotype of CYP27B1 contributes to autoimmune diseases. These data support therapeutic approaches aimed at targeting VitD effects on DCs.


Assuntos
25-Hidroxivitamina D3 1-alfa-Hidroxilase/genética , Cromossomos Humanos Par 12 , Células Dendríticas/imunologia , Esclerose Múltipla/genética , Vitamina D/metabolismo , Adulto , Idoso , Células Dendríticas/metabolismo , Células Dendríticas/patologia , Feminino , Regulação da Expressão Gênica , Ligação Genética , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/epidemiologia , Transdução de Sinais
8.
Clin Immunol ; 163: 96-107, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26762769

RESUMO

Multiple Sclerosis (MS) is an autoimmune disease treated by therapies targeting peripheral blood cells. We previously identified that expression of two MS-risk genes, the transcription factors EOMES and TBX21 (ET), was low in blood from MS and stable over time. Here we replicated the low ET expression in a new MS cohort (p<0.0007 for EOMES, p<0.028 for TBX21) and demonstrate longitudinal stability (p<10(-4)) and high heritability (h(2)=0.48 for EOMES) for this molecular phenotype. Genes whose expression correlated with ET, especially those controlling cell migration, further defined the phenotype. CD56+ cells and other subsets expressed lower levels of Eomes or T-bet protein and/or were under-represented in MS. EOMES and TBX21 risk SNP genotypes, and serum EBNA-1 titres were not correlated with ET expression, but HLA-DRB1*1501 genotype was. ET expression was normalised to healthy control levels with natalizumab, and was highly variable for glatiramer acetate, fingolimod, interferon-beta, dimethyl fumarate.


Assuntos
Esclerose Múltipla/genética , Proteínas com Domínio T/genética , Adulto , Idoso , Antígeno CD56 , Estudos de Casos e Controles , Movimento Celular , Fumarato de Dimetilo/uso terapêutico , Antígenos Nucleares do Vírus Epstein-Barr/sangue , Feminino , Cloridrato de Fingolimode/uso terapêutico , Regulação da Expressão Gênica , Predisposição Genética para Doença , Acetato de Glatiramer/uso terapêutico , Cadeias HLA-DRB1/genética , Humanos , Fatores Imunológicos/uso terapêutico , Imunossupressores/uso terapêutico , Interferon beta/uso terapêutico , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/tratamento farmacológico , Natalizumab/uso terapêutico , Polimorfismo de Nucleotídeo Único , Adulto Jovem
9.
Clin Immunol ; 151(1): 16-24, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24495857

RESUMO

We have identified a marked over-representation of transcription factors controlling differentiation of T, B, myeloid and NK cells among the 110 MS genes now known to be associated with multiple sclerosis (MS). To test if the expression of these genes might define molecular subtypes of MS, we interrogated their expression in blood in three independent cohorts of untreated MS (from Sydney and Adelaide) or clinically isolated syndrome (CIS, from San Francisco) patients. Expression of the transcription factors (TF) controlling T and NK cell differentiation, EOMES, TBX21 and other TFs was significantly lower in MS/CIS compared to healthy controls in all three cohorts. Expression was tightly correlated between these TFs, with other T/NK cell TFs, and to another downregulated gene, CCL5. Expression was stable over time, but did not predict disease phenotype. Optimal response to therapy might be indicated by normalization of expression of these genes in blood.


Assuntos
Esclerose Múltipla/genética , Proteínas com Domínio T/genética , Adolescente , Adulto , Idoso , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos B/patologia , Estudos de Casos e Controles , Diferenciação Celular , Quimiocina CCL5/genética , Quimiocina CCL5/imunologia , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Transdução de Sinais , Proteínas com Domínio T/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia
10.
Mult Scler ; 20(6): 675-85, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24126065

RESUMO

BACKGROUND: Multiple Sclerosis (MS) is an immune-mediated disease of the central nervous system which responds to therapies targeting circulating immune cells. OBJECTIVE: Our aim was to test if the T-cell activation gene expression pattern (TCAGE) we had previously described from whole blood was replicated in an independent cohort. METHODS: We used RNA-seq to interrogate the whole blood transcriptomes of 72 individuals (40 healthy controls, 32 untreated MS). A cohort of 862 control individuals from the Brisbane Systems Genetics Study (BSGS) was used to assess heritability and seasonal expression. The effect of interferon beta (IFNB) therapy on expression was evaluated. RESULTS: The MS/TCAGE association was replicated and rationalized to a single marker, ribosomal protein S6 (RPS6). Expression of RPS6 was higher in MS than controls (p<0.0004), and lower in winter than summer (p<4.6E-06). The seasonal pattern correlated with monthly UV light index (R=0.82, p<0.002), and was also identified in the BSGS cohort (p<0.0016). Variation in expression of RPS6 was not strongly heritable. RPS6 expression was reduced by IFNB therapy. CONCLUSIONS: These data support investigation of RPS6 as a potential therapeutic target and candidate biomarker for measuring clinical response to IFNB and other MS therapies, and of MS disease heterogeneity.


Assuntos
Fatores Imunológicos/uso terapêutico , Interferon beta/uso terapêutico , Esclerose Múltipla/metabolismo , RNA Mensageiro/sangue , Proteína S6 Ribossômica/metabolismo , Estações do Ano , Adulto , Biomarcadores/análise , Regulação para Baixo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/tratamento farmacológico , RNA/genética , Adulto Jovem
11.
Hepatology ; 55(6): 1700-10, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22234924

RESUMO

UNLABELLED: In patients with chronic hepatitis C virus (HCV) infection, several variants of the interleukin-28B (IL28B) gene have been shown to correlate significantly with a sustained virologic response (SVR). Recent evidence shows that determination of one single IL28B polymorphism, rs12979860, is sufficient for predicting treatment outcome. We examined whether the combined determination of the IL28B single-nucleotide polymorphisms (SNPs), rs12979860, rs8099917, rs12980275, and rs8103142, might improve the prediction of SVR in patients with HCV. In the study cohort, 54% of 942 patients with chronic HCV type 1 infection had SVR. The IL28B SNPs, rs12979860CC and rs8099917TT, correlated significantly with SVR (68% and 62%). The SNPs, rs12980275 and rs8103142, were in strong linkage disequilibrium with rs12979860 and were not included in further analysis. In homozygous carriers of the rs12979860 responder allele C, additional genotyping of the rs8099917 SNP had no effect on response prediction, whereas in carriers of the rs12979860 nonresponder allele, the rs8099917 SNP improved the response prediction. In heterozygous carriers of the rs12979860 nonresponder T allele, SVR rates were 55% in the presence of the rs8099917TT genotype and 40% in patients carrying the rs8099917 TG or GG genotype. Analysis of an independent confirmation cohort of 377 HCV type 1-infected patients verified the significant difference in SVR rates between the combined genotypes, rs12979860CT/rs8099917TT and rs12979860CT/rs8099917TG (38% versus 21%; P = 0.018). CONCLUSION: Treatment outcome prediction could not be improved in homozygous carriers of the IL28B rs12979860 C responder allele by the additional determination of the rs8099917 SNP. There is evidence that a significant proportion of heterozygous carriers of the rs12979860 T nonresponder allele can profit with respect to SVR prediction by further determination of the rs8099917 SNP. (HEPATOLOGY 2012;55:1700-1710).


Assuntos
Hepatite C Crônica/tratamento farmacológico , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Adulto , Estudos de Coortes , Quimioterapia Combinada , Feminino , Genótipo , Haplótipos , Hepatite C Crônica/genética , Hepatite C Crônica/virologia , Humanos , Interferons , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
12.
Hum Mol Genet ; 19(11): 2134-43, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20190274

RESUMO

Multiple sclerosis (MS) is an autoimmune disease with a genetic component, caused at least in part by aberrant lymphocyte activity. The whole blood mRNA transcriptome was measured for 99 untreated MS patients: 43 primary progressive MS, 20 secondary progressive MS, 36 relapsing remitting MS and 45 age-matched healthy controls. The ANZgene Multiple Sclerosis Genetics Consortium genotyped more than 300 000 SNPs for 115 of these samples. Transcription from genes on translational regulation, oxidative phosphorylation, immune synapse and antigen presentation pathways was markedly increased in all forms of MS. Expression of genes tagging T cells was also upregulated (P < 10(-12)) in MS. A T cell gene signature predicts disease state with a concordance index of 0.79 with age and gender as co-variables, but the signature is not associated with clinical course or disability. The ANZgene genome wide association screen identified two novel regions with genome wide significance: one encoding the T cell co-stimulatory molecule, CD40; the other a region on chromosome 12q13-14. The CD40 haplotype associated with increased MS susceptibility has decreased gene expression in MS (P < 0.0007). The second MS susceptibility region includes 17 genes on 12q13-14 in tight linkage disequilibrium. Of these, only 13 are expressed in leukocytes, and of these the expression of one, FAM119B, is much lower in the susceptibility haplotype (P < 10(-14)). Overall, these data indicate dysregulation of T cells can be detected in the whole blood of untreated MS patients, and supports targeting of activated T cells in therapy for all forms of MS.


Assuntos
Antígenos CD40/genética , Cromossomos Humanos Par 12/genética , Regulação da Expressão Gênica/genética , Esclerose Múltipla/metabolismo , Esclerose Múltipla/fisiopatologia , RNA Mensageiro/sangue , Linfócitos T/metabolismo , Apresentação de Antígeno/genética , Perfilação da Expressão Gênica , Genótipo , Haplótipos/genética , Humanos , Desequilíbrio de Ligação , Esclerose Múltipla/genética , Fosforilação Oxidativa
13.
Blood ; 115(16): 3258-68, 2010 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-20185587

RESUMO

To delineate the relative roles of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and Fas ligand in lymphocyte biology and lymphoproliferative disease, we generated mice defective in both molecules. B6.GT mice develop severe polyclonal lymphoproliferative disease because of accumulating CD3(+)CD4(-)CD8(-)B220(+) T cells, CD4(+) and CD8(+) T cells, and follicular B cells, and mice die prematurely from extreme lymphocytosis, thrombocytopenia, and hemorrhage. Accumulating lymphocytes resembled antigen-experienced lymphocytes, consistent with the maximal resistance of B6.GT CD4(+) and CD8(+) T cell to activation-induced cell death. More specifically, we show that TRAIL contributes to Fas ligand-mediated activation-induced cell death and controls lymphocyte apoptosis in the presence of interferon-gamma once antigen stimulation is removed. Furthermore, dysregulated lymphocyte homeostasis results in the production of anti-DNA and rheumatoid factor autoantibodies, as well as antiplatelet IgM and IgG causing thrombocytopenia. Thus, B6.GT mice reveal new roles for TRAIL in lymphocyte homeostasis and autoimmune lymphoproliferative syndromes and are a model of spontaneous idiopathic thrombocytopenia purpura secondary to lymphoproliferative disease.


Assuntos
Proteína Ligante Fas/deficiência , Transtornos Linfoproliferativos/genética , Púrpura Trombocitopênica Idiopática/genética , Ligante Indutor de Apoptose Relacionado a TNF/deficiência , Animais , Autoanticorpos/imunologia , Separação Celular , Ensaio de Imunoadsorção Enzimática , Proteína Ligante Fas/genética , Citometria de Fluxo , Transtornos Linfoproliferativos/imunologia , Transtornos Linfoproliferativos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Ligante Indutor de Apoptose Relacionado a TNF/genética
14.
J Immunol ; 184(5): 2512-7, 2010 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-20097866

RESUMO

Common genetic variants of IL-7 receptor alpha (IL-7Ralpha) have recently been shown to affect susceptibility to multiple sclerosis (MS) and type 1 diabetes, and survival following bone marrow transplantation. Transcription of the gene produces two dominant isoforms, with or without exon 6, which code for membrane-bound or soluble IL-7Ralpha, respectively. The haplotypes produce different isoform ratios. We have tested IL-7Ralpha mRNA expression in cell subsets and in models of T cell homeostasis, activation, tolerance, and differentiation into regulatory T cell/Th1/Th2/Th17, memory, and dendritic cells (DCs) under the hypothesis that the conditions in which haplotype differences are maximal are those likely to be the basis for their association with disease pathogenesis. Maximal differences between haplotypes were found in DCs, where the ligand is mainly thymic stromal lymphopoietin (TSLP). The MS-protective haplotype produces a much lower ratio of soluble to membrane-bound receptor, and so potentially, DCs of this haplotype are more responsive to TSLP. The TSLP/IL-7Ralpha interaction on DCs is known to be critical for production of thymic regulatory T cells, and reduced production of these cells in MS susceptibility haplotypes may be a basis for its association with this disease. IL-7Ralpha mRNA expression varies greatly through cell differentiation so that it may be a useful marker for cell states. We also show that serum levels of soluble receptor are much higher for the MS susceptibility haplotype (p = 4 x 10(-13)). Because signaling through IL-7Ralpha controls T cell regulation, this haplotype difference is likely to affect the immunophenotype and disease pathogenesis.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Células Dendríticas/metabolismo , Perfilação da Expressão Gênica , Haplótipos , Receptores de Interleucina-7/genética , Processamento Alternativo , Linfócitos T CD4-Positivos/citologia , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/citologia , Ensaio de Imunoadsorção Enzimática , Feminino , Genótipo , Homeostase/genética , Humanos , Interleucina-17/metabolismo , Masculino , Esclerose Múltipla/genética , Ligação Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Interleucina-7/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T Auxiliares-Indutores/citologia , Linfócitos T Auxiliares-Indutores/metabolismo , Células Th1/citologia , Células Th1/metabolismo , Células Th2/citologia , Células Th2/metabolismo , Linfopoietina do Estroma do Timo
15.
Proc Natl Acad Sci U S A ; 106(13): 5264-9, 2009 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-19237575

RESUMO

Multiple sclerosis (MS) is an inflammatory disease of the central nervous system associated with demyelination and axonal loss. A whole genome association scan suggested that allelic variants in the CD58 gene region, encoding the costimulatory molecule LFA-3, are associated with risk of developing MS. We now report additional genetic evidence, as well as resequencing and fine mapping of the CD58 locus in patients with MS and control subjects. These efforts identify a CD58 variant that provides further evidence of association with MS (P = 1.1 x 10(-6), OR 0.82) and the single protective effect within the CD58 locus is captured by the rs2300747(G) allele. This protective rs2300747(G) allele is associated with a dose-dependent increase in CD58 mRNA expression in lymphoblastic cell lines (P = 1.1 x 10(-10)) and in peripheral blood mononuclear cells from MS subjects (P = 0.0037). This protective effect of enhanced CD58 expression on circulating mononuclear cells in patients with MS is supported by finding that CD58 mRNA expression is higher in MS subjects during clinical remission. Functional investigations suggest a potential mechanism whereby increases in CD58 expression, mediated by the protective allele, up-regulate the expression of transcription factor FoxP3 through engagement of the CD58 receptor, CD2, leading to the enhanced function of CD4(+)CD25(high) regulatory T cells that are defective in subjects with MS.


Assuntos
Antígenos CD58/genética , Esclerose Múltipla/genética , RNA Mensageiro/análise , Alelos , Antígenos CD2 , Estudos de Casos e Controles , Mapeamento Cromossômico , Fatores de Transcrição Forkhead , Humanos , Leucócitos Mononucleares , Indução de Remissão , Análise de Sequência , Linfócitos T Reguladores/imunologia , Regulação para Cima
16.
PLoS Med ; 8(9): e1001092, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21931540

RESUMO

BACKGROUND: To date, drug response genes have not proved as useful in clinical practice as was anticipated at the start of the genomic era. An exception is in the treatment of chronic hepatitis C virus (HCV) genotype 1 infection with pegylated interferon-alpha and ribavirin (PegIFN/R). Viral clearance is achieved in 40%-50% of patients. Interleukin 28B (IL28B) genotype predicts treatment-induced and spontaneous clearance. To improve the predictive value of this genotype, we studied the combined effect of variants of IL28B with human leukocyte antigen C (HLA-C), and its ligands the killer immunoglobulin-like receptors (KIR), which have previously been implicated in HCV viral control. METHODS AND FINDINGS: We genotyped chronic hepatitis C (CHC) genotype 1 patients with PegIFN/R treatment-induced clearance (n = 417) and treatment failure (n = 493), and 234 individuals with spontaneous clearance, for HLA-C C1 versus C2, presence of inhibitory and activating KIR genes, and two IL28B SNPs, rs8099917 and rs12979860. All individuals were Europeans or of European descent. IL28B SNP rs8099917 "G" was associated with absence of treatment-induced clearance (odds ratio [OR] 2.19, p = 1.27×10(-8), 1.67-2.88) and absence of spontaneous clearance (OR 3.83, p = 1.71×10(-14), 2.67-5.48) of HCV, as was rs12979860, with slightly lower ORs. The HLA-C C2C2 genotype was also over-represented in patients who failed treatment (OR 1.52, p = 0.024, 1.05-2.20), but was not associated with spontaneous clearance. Prediction of treatment failure improved from 66% with IL28B to 80% using both genes in this cohort (OR 3.78, p = 8.83×10(-6), 2.03-7.04). There was evidence that KIR2DL3 and KIR2DS2 carriage also altered HCV treatment response in combination with HLA-C and IL28B. CONCLUSIONS: Genotyping for IL28B, HLA-C, and KIR genes improves prediction of HCV treatment response. These findings support a role for natural killer (NK) cell activation in PegIFN/R treatment-induced clearance, partially mediated by IL28B.


Assuntos
Antígenos HLA-C/genética , Hepacivirus/patogenicidade , Hepatite C Crônica/terapia , Interleucinas/genética , Adulto , Alelos , Antivirais/uso terapêutico , Estudos de Casos e Controles , Estudos de Coortes , Estudos Transversais , Quimioterapia Combinada , Feminino , Genótipo , Hepacivirus/imunologia , Hepatite C Crônica/genética , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/uso terapêutico , Interferons , Células Matadoras Naturais/imunologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Farmacogenética/métodos , Polimorfismo de Nucleotídeo Único , Valor Preditivo dos Testes , RNA Viral/análise , Receptores KIR/genética , Receptores KIR2DL3/genética , Ribavirina/uso terapêutico , Resultado do Tratamento , Carga Viral , População Branca
17.
Sci Rep ; 10(1): 193, 2020 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-31932685

RESUMO

Translating the findings of genome wide association studies (GWAS) to new therapies requires identification of the relevant immunological contexts to interrogate for genetic effects. In one of the largest GWAS, more than 200 risk loci have been identified for Multiple Sclerosis (MS) susceptibility. Infection with Epstein-Barr virus (EBV) appears to be necessary for the development of Multiple Sclerosis (MS). Many MS risk loci are associated with altered gene expression in EBV infected B cells (LCLs). We have interrogated this immunological context to identify interaction between MS risk loci and EBV DNA copy number, intrinsic growth rate and EBV encoded miRNA expression. The EBV DNA copy number was associated with significantly more risk alleles for MS than for other diseases or traits. EBV miRNAs BART4-3p and BART3-5p were highly associated with EBV DNA copy number and MS risk loci. The poliovirus receptor (PVR) risk SNP was associated with EBV DNA copy number, PVR and miRNA expression. Targeting EBV miRNAs BART4-3p and BART3-5p, and the gene PVR, may provide therapeutic benefit in MS. This study also indicates how immunological context and risk loci interactions can be exploited to validate and develop novel therapeutic approaches.


Assuntos
Variações do Número de Cópias de DNA , Infecções por Vírus Epstein-Barr/complicações , Herpesvirus Humano 4/genética , Interações Hospedeiro-Patógeno/genética , Esclerose Múltipla/patologia , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Estudos de Coortes , DNA Viral/análise , DNA Viral/genética , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/virologia , Regulação da Expressão Gênica , Estudo de Associação Genômica Ampla , Herpesvirus Humano 4/isolamento & purificação , Humanos , MicroRNAs/genética , Esclerose Múltipla/epidemiologia , Esclerose Múltipla/virologia , Fenótipo
18.
J Allergy Clin Immunol ; 121(5): 1148-1154.e3, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18405956

RESUMO

BACKGROUND: Polymorphisms in the plant homeodomain finger protein 11 gene (PHF11) are associated with increased total serum IgE levels, asthma, and severe atopic dermatitis (AD) in children. Although PHF11 includes a plant homeodomain, a motif often found in transcriptional regulators, the function of PHF11 has not been investigated. OBJECTIVE: We sought to test (1) whether PHF11 regulates the transcription of genes involved in allergic disorders and (2) whether polymorphisms in PHF11 predict changes in the expression or function of this gene. METHODS: Microarray analysis was used to examine the expression of PHF11 in different immune cell subsets, and the function of PHF11 was tested by using small interfering RNA-induced knockdown or overexpression of PHF11 in primary CD4+ T cells or Jurkat T cells. Genotype-dependent effects on PHF11 expression were tested by using an allele-specific gene expression, and the transcriptional activity of PHF11 was determined by using luciferase hybrid gene reporter assays and in vitro DNA-binding electromobility shift assays. RESULTS: PHF11 expression was higher in T(H)1 cells relative to that in T(H)2 cells, and knockdown of PHF11 expression reduced expression of the T(H)1-type cytokines IFN-gamma and IL-2. The G-allele of a 3' untranslated region polymorphism associated with AD was correlated with reduced abundance of PHF11 RNA in T(H)1 cells, as well as an increase in a PHF11 isoform lacking exon II. Evidence was also found for a physical and functional interaction between PHF11 and the p65 subunit of nuclear factor kappaB. CONCLUSION: PHF11 is a regulator of T(H)1-type cytokine gene expression. The reduction in PHF11 expression seen with an AD-associated genotype could contribute to the strong T(H)2 responses that characterize many allergic individuals.


Assuntos
Proteínas de Ligação a DNA/genética , Hipersensibilidade Imediata/genética , Células Th1/imunologia , Células Th2/imunologia , Fatores de Transcrição/genética , Criança , Proteínas de Ligação a DNA/imunologia , Ensaio de Desvio de Mobilidade Eletroforética , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Hipersensibilidade Imediata/imunologia , Células Jurkat , NF-kappa B/imunologia , NF-kappa B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Sítios de Splice de RNA , RNA Interferente Pequeno , Fatores de Transcrição/imunologia , Transcrição Gênica , Transfecção
19.
Genome Med ; 11(1): 26, 2019 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31039804

RESUMO

BACKGROUND: Genome wide association studies have identified > 200 susceptibility loci accounting for much of the heritability of multiple sclerosis (MS). Epstein-Barr virus (EBV), a memory B cell tropic virus, has been identified as necessary but not sufficient for development of MS. The molecular and immunological basis for this has not been established. Infected B cell proliferation is driven by signalling through the EBV produced cell surface protein LMP1, a homologue of the MS risk gene CD40. METHODS: We have investigated transcriptomes of B cells and EBV-infected B cells at Latency III (LCLs) and identified MS risk genes with altered expression on infection and with expression levels associated with the MS risk genotype (LCLeQTLs). The association of LCLeQTL genomic burden with EBV phenotypes in vitro and in vivo was examined. The risk genotype effect on LCL proliferation with CD40 stimulation was assessed. RESULTS: These LCLeQTL MS risk SNP:gene pairs (47 identified) were over-represented in genes dysregulated between B and LCLs (p < 1.53 × 10-4), and as target loci of the EBV transcription factor EBNA2 (p < 3.17 × 10-16). Overall genetic burden of LCLeQTLs was associated with some EBV phenotypes but not others. Stimulation of the CD40 pathway by CD40L reduced LCL proliferation (p < 0.001), dependent on CD40 and TRAF3 MS risk genotypes. Both CD40 and TRAF3 risk SNPs are in binding sites for the EBV transcription factor EBNA2, with expression of each correlated with EBNA2 expression dependent on genotype. CONCLUSIONS: These data indicate targeting EBV may be of therapeutic benefit in MS.


Assuntos
Linfócitos B/metabolismo , Antígenos CD4/genética , Herpesvirus Humano 4/fisiologia , Esclerose Múltipla/genética , Polimorfismo de Nucleotídeo Único , Fator 3 Associado a Receptor de TNF/genética , Linfócitos B/virologia , Células Cultivadas , Endonucleases/genética , Herpesvirus Humano 4/patogenicidade , Humanos , Locos de Características Quantitativas , Transcriptoma , Latência Viral , Replicação Viral
20.
BMC Med Genet ; 9: 17, 2008 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-18366677

RESUMO

BACKGROUND: Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS). Although the pathogenesis of MS remains unknown, it is widely regarded as an autoimmune disease mediated by T-lymphocytes directed against myelin proteins and/or other oligodendrocyte epitopes. METHODS: In this study we investigated the gene expression profiles of peripheral blood cells from patients with RRMS during the relapse and the remission phases utilizing gene microarray technology. Dysregulated genes encoded in regions associated with MS susceptibility from genomic screens or previous transcriptomic studies were identified. The proximal promoter region polymorphisms of two genes were tested for association with disease and expression level. RESULTS: Distinct sets of dysregulated genes during the relapse and remission phases were identified including genes involved in apoptosis and inflammation. Three of these dysregulated genes have been previously implicated with MS susceptibility in genomic screens: TGFbeta1, CD58 and DBC1. TGFbeta1 has one common SNP in the proximal promoter: -508 T>C (rs1800469). Genotyping two Australian trio sets (total 620 families) found a trend for over-transmission of the T allele in MS in females (p < 0.13). Upregulation of CD58 and DBC1 in remission is consistent with their putative roles in promoting regulatory T cells and reducing cell proliferation, respectively. A fourth gene, ALOX5, is consistently found over-expressed in MS. Two common genetic variants were confirmed in the ALOX5 putative promoter: -557 T>C (rs12762303) and a 6 bp tandem repeat polymorphism (GGGCGG) between position -147 and -176; but no evidence for transmission distortion found. CONCLUSION: The dysregulation of these genes tags their metabolic pathways for further investigation for potential therapeutic intervention.


Assuntos
Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Esclerose Múltipla Recidivante-Remitente/genética , Adulto , Idoso , Araquidonato 5-Lipoxigenase/genética , Estudos de Casos e Controles , Feminino , Marcadores Genéticos , Variação Genética , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNA , Fator de Crescimento Transformador beta1/genética
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