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1.
Intern Med J ; 52(12): 2046-2067, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36478370

RESUMEN

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.


Asunto(s)
Amiloidosis , Cardiomiopatías , Insuficiencia Cardíaca , Humanos , Calidad de Vida , Amiloidosis/diagnóstico , Amiloidosis/terapia , Amiloidosis/complicaciones , Insuficiencia Cardíaca/diagnóstico , Pronóstico , Bortezomib/uso terapéutico , Cardiomiopatías/diagnóstico
2.
Genes Immun ; 22(4): 227-233, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34163021

RESUMEN

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.


Asunto(s)
Esclerosis Múltiple , Humanos , Leucocitos Mononucleares , Esclerosis Múltiple/tratamiento farmacológico , Esclerosis Múltiple/genética , Vitamina D , Vitamina D3 24-Hidroxilasa/genética
3.
Hum Mol Genet ; 28(2): 269-278, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30285234

RESUMEN

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.


Asunto(s)
Enfermedades Autoinmunes/genética , Diferenciación Celular/genética , Factores Reguladores del Interferón/genética , Monocitos/citología , Factores de Transcripción/genética , Vitamina D/farmacología , Vitaminas/farmacología , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Células Dendríticas/citología , Geografía Médica , Humanos
4.
Genes Immun ; 21(5): 335-347, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33037402

RESUMEN

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.


Asunto(s)
Metilación de ADN , Epigenoma , Células Madre Hematopoyéticas/metabolismo , Esclerosis Múltiple/genética , Vitamina D/metabolismo , Adulto , Islas de CpG , Femenino , Cadenas HLA-DRB1/genética , Hematopoyesis , Células Madre Hematopoyéticas/citología , Humanos , Células Asesinas Naturales/citología , Células Asesinas Naturales/metabolismo , Masculino , Persona de Mediana Edad , Monocitos/citología , Monocitos/metabolismo , Esclerosis Múltiple/metabolismo , Co-Represor 2 de Receptor Nuclear/genética , Unión Proteica , Receptores de Calcitriol/metabolismo , Factores de Transcripción/genética
5.
Genes Immun ; 21(2): 91-99, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31619767

RESUMEN

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.


Asunto(s)
Linfocitos B/metabolismo , Herpesvirus Humano 4/genética , Esclerosis Múltiple/genética , Linfocitos B/fisiología , Metilación de ADN/genética , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/metabolismo , Infecciones por Virus de Epstein-Barr/virología , Herpesvirus Humano 4/metabolismo , Humanos , Regiones Promotoras Genéticas/genética
6.
Heart Lung Circ ; 29(4): 575-583, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32001152

RESUMEN

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.


Asunto(s)
Neuropatías Amiloides Familiares , Cardiomiopatías , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Neuropatías Amiloides Familiares/complicaciones , Neuropatías Amiloides Familiares/genética , Neuropatías Amiloides Familiares/terapia , Cardiomiopatías/etiología , Cardiomiopatías/genética , Cardiomiopatías/terapia , Humanos , Prealbúmina/genética
7.
Hum Mol Genet ; 23(6): 1425-34, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24158849

RESUMEN

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.


Asunto(s)
25-Hidroxivitamina D3 1-alfa-Hidroxilasa/genética , Cromosomas Humanos Par 12 , Células Dendríticas/inmunología , Esclerosis Múltiple/genética , Vitamina D/metabolismo , Adulto , Anciano , Células Dendríticas/metabolismo , Células Dendríticas/patología , Femenino , Regulación de la Expresión Génica , Ligamiento Genético , Predisposición Genética a la Enfermedad , Variación Genética , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/epidemiología , Transducción de Señal
8.
Clin Immunol ; 163: 96-107, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26762769

RESUMEN

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.


Asunto(s)
Esclerosis Múltiple/genética , Proteínas de Dominio T Box/genética , Adulto , Anciano , Antígeno CD56 , Estudios de Casos y Controles , Movimiento Celular , Dimetilfumarato/uso terapéutico , Antígenos Nucleares del Virus de Epstein-Barr/sangre , Femenino , Clorhidrato de Fingolimod/uso terapéutico , Regulación de la Expresión Génica , Predisposición Genética a la Enfermedad , Acetato de Glatiramer/uso terapéutico , Cadenas HLA-DRB1/genética , Humanos , Factores Inmunológicos/uso terapéutico , Inmunosupresores/uso terapéutico , Interferón beta/uso terapéutico , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/tratamiento farmacológico , Natalizumab/uso terapéutico , Polimorfismo de Nucleótido Simple , Adulto Joven
9.
Clin Immunol ; 151(1): 16-24, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24495857

RESUMEN

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.


Asunto(s)
Esclerosis Múltiple/genética , Proteínas de Dominio T Box/genética , Adolescente , Adulto , Anciano , Linfocitos B/inmunología , Linfocitos B/metabolismo , Linfocitos B/patología , Estudios de Casos y Controles , Diferenciación Celular , Quimiocina CCL5/genética , Quimiocina CCL5/inmunología , Estudios de Cohortes , Femenino , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Humanos , Células Asesinas Naturales/inmunología , Células Asesinas Naturales/metabolismo , Células Asesinas Naturales/patología , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Transducción de Señal , Proteínas de Dominio T Box/inmunología , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linfocitos T/patología
10.
Mult Scler ; 20(6): 675-85, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24126065

RESUMEN

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.


Asunto(s)
Factores Inmunológicos/uso terapéutico , Interferón beta/uso terapéutico , Esclerosis Múltiple/metabolismo , ARN Mensajero/sangre , Proteína S6 Ribosómica/metabolismo , Estaciones del Año , Adulto , Biomarcadores/análisis , Regulación hacia Abajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/tratamiento farmacológico , ARN/genética , Adulto Joven
11.
Hepatology ; 55(6): 1700-10, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22234924

RESUMEN

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).


Asunto(s)
Hepatitis C Crónica/tratamiento farmacológico , Interleucinas/genética , Polimorfismo de Nucleótido Simple , Adulto , Estudios de Cohortes , Quimioterapia Combinada , Femenino , Genotipo , Haplotipos , Hepatitis C Crónica/genética , Hepatitis C Crónica/virología , Humanos , Interferones , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
12.
Hum Mol Genet ; 19(11): 2134-43, 2010 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-20190274

RESUMEN

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.


Asunto(s)
Antígenos CD40/genética , Cromosomas Humanos Par 12/genética , Regulación de la Expresión Génica/genética , Esclerosis Múltiple/metabolismo , Esclerosis Múltiple/fisiopatología , ARN Mensajero/sangre , Linfocitos T/metabolismo , Presentación de Antígeno/genética , Perfilación de la Expresión Génica , Genotipo , Haplotipos/genética , Humanos , Desequilibrio de Ligamiento , Esclerosis Múltiple/genética , Fosforilación Oxidativa
13.
Blood ; 115(16): 3258-68, 2010 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-20185587

RESUMEN

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.


Asunto(s)
Proteína Ligando Fas/deficiencia , Trastornos Linfoproliferativos/genética , Púrpura Trombocitopénica Idiopática/genética , Ligando Inductor de Apoptosis Relacionado con TNF/deficiencia , Animales , Autoanticuerpos/inmunología , Separación Celular , Ensayo de Inmunoadsorción Enzimática , Proteína Ligando Fas/genética , Citometría de Flujo , Trastornos Linfoproliferativos/inmunología , Trastornos Linfoproliferativos/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Púrpura Trombocitopénica Idiopática/inmunología , Púrpura Trombocitopénica Idiopática/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/patología , Linfocitos T/inmunología , Linfocitos T/patología , Ligando Inductor de Apoptosis Relacionado con TNF/genética
14.
J Immunol ; 184(5): 2512-7, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-20097866

RESUMEN

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.


Asunto(s)
Linfocitos T CD4-Positivos/metabolismo , Células Dendríticas/metabolismo , Perfilación de la Expresión Génica , Haplotipos , Receptores de Interleucina-7/genética , Empalme Alternativo , Linfocitos T CD4-Positivos/citología , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/citología , Ensayo de Inmunoadsorción Enzimática , Femenino , Genotipo , Homeostasis/genética , Humanos , Interleucina-17/metabolismo , Masculino , Esclerosis Múltiple/genética , Unión Proteica , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Interleucina-7/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T Colaboradores-Inductores/citología , Linfocitos T Colaboradores-Inductores/metabolismo , Células TH1/citología , Células TH1/metabolismo , Células Th2/citología , Células Th2/metabolismo , Linfopoyetina del Estroma Tímico
15.
Proc Natl Acad Sci U S A ; 106(13): 5264-9, 2009 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-19237575

RESUMEN

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.


Asunto(s)
Antígenos CD58/genética , Esclerosis Múltiple/genética , ARN Mensajero/análisis , Alelos , Antígenos CD2 , Estudios de Casos y Controles , Mapeo Cromosómico , Factores de Transcripción Forkhead , Humanos , Leucocitos Mononucleares , Inducción de Remisión , Análisis de Secuencia , Linfocitos T Reguladores/inmunología , Regulación hacia Arriba
16.
PLoS Med ; 8(9): e1001092, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21931540

RESUMEN

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.


Asunto(s)
Antígenos HLA-C/genética , Hepacivirus/patogenicidad , Hepatitis C Crónica/terapia , Interleucinas/genética , Adulto , Alelos , Antivirales/uso terapéutico , Estudios de Casos y Controles , Estudios de Cohortes , Estudios Transversales , Quimioterapia Combinada , Femenino , Genotipo , Hepacivirus/inmunología , Hepatitis C Crónica/genética , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/virología , Humanos , Interferón-alfa/uso terapéutico , Interferones , Células Asesinas Naturales/inmunología , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Farmacogenética/métodos , Polimorfismo de Nucleótido Simple , Valor Predictivo de las Pruebas , ARN Viral/análisis , Receptores KIR/genética , Receptores KIR2DL3/genética , Ribavirina/uso terapéutico , Resultado del Tratamiento , Carga Viral , Población Blanca
17.
Sci Rep ; 10(1): 193, 2020 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-31932685

RESUMEN

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.


Asunto(s)
Variaciones en el Número de Copia de ADN , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4/genética , Interacciones Huésped-Patógeno/genética , Esclerosis Múltiple/patología , Polimorfismo de Nucleótido Simple , Sitios de Carácter Cuantitativo , Estudios de Cohortes , ADN Viral/análisis , ADN Viral/genética , Infecciones por Virus de Epstein-Barr/genética , Infecciones por Virus de Epstein-Barr/virología , Regulación de la Expresión Génica , Estudio de Asociación del Genoma Completo , Herpesvirus Humano 4/aislamiento & purificación , Humanos , MicroARNs/genética , Esclerosis Múltiple/epidemiología , Esclerosis Múltiple/virología , Fenotipo
18.
J Allergy Clin Immunol ; 121(5): 1148-1154.e3, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18405956

RESUMEN

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.


Asunto(s)
Proteínas de Unión al ADN/genética , Hipersensibilidad Inmediata/genética , Células TH1/inmunología , Células Th2/inmunología , Factores de Transcripción/genética , Niño , Proteínas de Unión al ADN/inmunología , Ensayo de Cambio de Movilidad Electroforética , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Hipersensibilidad Inmediata/inmunología , Células Jurkat , FN-kappa B/inmunología , FN-kappa B/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Sitios de Empalme de ARN , ARN Interferente Pequeño , Factores de Transcripción/inmunología , Transcripción Genética , Transfección
19.
Genome Med ; 11(1): 26, 2019 04 30.
Artículo en Inglés | MEDLINE | ID: mdl-31039804

RESUMEN

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.


Asunto(s)
Linfocitos B/metabolismo , Antígenos CD4/genética , Herpesvirus Humano 4/fisiología , Esclerosis Múltiple/genética , Polimorfismo de Nucleótido Simple , Factor 3 Asociado a Receptor de TNF/genética , Linfocitos B/virología , Células Cultivadas , Endonucleasas/genética , Herpesvirus Humano 4/patogenicidad , Humanos , Sitios de Carácter Cuantitativo , Transcriptoma , Latencia del Virus , Replicación Viral
20.
BMC Med Genet ; 9: 17, 2008 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-18366677

RESUMEN

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.


Asunto(s)
Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Esclerosis Múltiple Recurrente-Remitente/genética , Adulto , Anciano , Araquidonato 5-Lipooxigenasa/genética , Estudios de Casos y Controles , Femenino , Marcadores Genéticos , Variación Genética , Genotipo , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Factor de Crecimiento Transformador beta1/genética
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