Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 79
Filtrar
1.
JCI Insight ; 9(12)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38912583

RESUMO

Patients with autosomal dominant polycystic kidney disease (ADPKD), a genetic disease due to mutations of the PKD1 or PKD2 gene, show signs of complement activation in the urine and cystic fluid, but their pathogenic role in cystogenesis is unclear. We tested the causal relationship between complement activation and cyst growth using a Pkd1KO renal tubular cell line and newly generated conditional Pkd1-/- C3-/- mice. Pkd1-deficient tubular cells have increased expression of complement-related genes (C3, C5, CfB, C3ar, and C5ar1), while the gene and protein expression of complement regulators DAF, CD59, and Crry is decreased. Pkd1-/- C3-/- mice are unable to fully activate the complement cascade and are characterized by a significantly slower kidney cystogenesis, preserved renal function, and reduced intrarenal inflammation compared with Pkd1-/- C3+/+ controls. Transgenic expression of the cytoplasmic C-terminal tail of Pkd1 in Pkd1KO cells lowered C5ar1 expression, restored Daf levels, and reduced cell proliferation. Consistently, both DAF overexpression and pharmacological inhibition of C5aR1 (but not C3aR) reduced Pkd1KO cell proliferation. In conclusion, the loss of Pkd1 promotes unleashed activation of locally produced complement by downregulating DAF expression in renal tubular cells. Increased C5a formation and C5aR1 activation in tubular cells promotes cyst growth, offering a new therapeutic target.


Assuntos
Antígenos CD55 , Complemento C3 , Camundongos Knockout , Rim Policístico Autossômico Dominante , Animais , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/patologia , Rim Policístico Autossômico Dominante/metabolismo , Camundongos , Antígenos CD55/genética , Antígenos CD55/metabolismo , Complemento C3/genética , Complemento C3/metabolismo , Receptor da Anafilatoxina C5a/metabolismo , Receptor da Anafilatoxina C5a/genética , Modelos Animais de Doenças , Ativação do Complemento , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Humanos , Proliferação de Células , Masculino , Linhagem Celular , Receptores de Complemento 3b/genética , Receptores de Complemento 3b/metabolismo
2.
Clin Exp Immunol ; 216(1): 45-54, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38133636

RESUMO

Cold agglutinin disease (CAD) is a rare B-cell lymphoproliferative disorder of the bone marrow, manifested by autoimmune hemolytic anemia caused by binding of monoclonal IgM autoantibodies to the I antigen. Underlying genetic changes have previously been reported, but their impact on gene expression profile has been unknown. Here, we define differentially expressed genes in CAD B cells. To unravel downstream alteration in cellular pathways, gene expression by RNA sequencing was undertaken. Clonal B-cell samples from 12 CAD patients and IgM-expressing memory B cells from 4 healthy individuals were analyzed. Differential expression analysis and filtering resulted in 93 genes with significant differential expression. Top upregulated genes included SLC4A1, SPTA1, YBX3, TESC, HBD, AHSP, TRAF1, HBA2, RHAG, CA1, SPTB, IL10, UBASH3B, ALAS2, HBA1, CRYM, RGCC, KANK2, and IGHV4-34. They were upregulated at least 8-fold, while complement receptor 1 (CR1/CD35) was downregulated 11-fold in clonal CAD B cells compared to control B cells. Flow cytometry analyses further confirmed reduced CR1 (CD35) protein expression by clonal CAD IgM+ B cells compared to IgM+ memory B cells in controls. CR1 (CD35) is an important negative regulator of B-cell activation and differentiation. Therefore, reduced CR1 (CD35) expression may increase activation, proliferation, and antibody production in CAD-associated clonal B cells.


Assuntos
Anemia Hemolítica Autoimune , Humanos , Anemia Hemolítica Autoimune/genética , Anemia Hemolítica Autoimune/metabolismo , Regulação para Baixo , Receptores de Complemento 3b/genética , Linfócitos B , Imunoglobulina M , Perfilação da Expressão Gênica , Proteínas Sanguíneas/genética , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , 5-Aminolevulinato Sintetase/genética , 5-Aminolevulinato Sintetase/metabolismo
3.
Nat Commun ; 12(1): 7172, 2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34887405

RESUMO

Complement receptor of immunoglobulin superfamily (CRIg) is expressed on liver macrophages and directly binds complement component C3b or Gram-positive bacteria to mediate phagocytosis. CRIg plays important roles in several immune-mediated diseases, but it is not clear how its pathogen recognition and phagocytic functions maintain homeostasis and prevent disease. We previously associated cytolysin-positive Enterococcus faecalis with severity of alcohol-related liver disease. Here, we demonstrate that CRIg is reduced in liver tissues from patients with alcohol-related liver disease. CRIg-deficient mice developed more severe ethanol-induced liver disease than wild-type mice; disease severity was reduced with loss of toll-like receptor 2. CRIg-deficient mice were less efficient than wild-type mice at clearing Gram-positive bacteria such as Enterococcus faecalis that had translocated from gut to liver. Administration of the soluble extracellular domain CRIg-Ig protein protected mice from ethanol-induced steatohepatitis. Our findings indicate that ethanol impairs hepatic clearance of translocated pathobionts, via decreased hepatic CRIg, which facilitates progression of liver disease.


Assuntos
Enterococcus faecalis/imunologia , Infecções por Bactérias Gram-Positivas/imunologia , Hepatopatias Alcoólicas/imunologia , Macrófagos/imunologia , Receptores de Complemento 3b/imunologia , Receptores de Complemento/imunologia , Animais , Translocação Bacteriana , Complemento C3b/imunologia , Enterococcus faecalis/fisiologia , Etanol/efeitos adversos , Feminino , Trato Gastrointestinal/microbiologia , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Fígado/efeitos dos fármacos , Fígado/imunologia , Fígado/microbiologia , Hepatopatias Alcoólicas/etiologia , Hepatopatias Alcoólicas/genética , Hepatopatias Alcoólicas/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Complemento/deficiência , Receptores de Complemento/genética , Receptores de Complemento 3b/genética
4.
Genes (Basel) ; 12(12)2021 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-34946939

RESUMO

The presence of complement activation products at sites of pathology in post-mortem Alzheimer's disease (AD) brains is well known. Recent evidence from genome-wide association studies (GWAS), combined with the demonstration that complement activation is pivotal in synapse loss in AD, strongly implicates complement in disease aetiology. Genetic variations in complement genes are widespread. While most variants individually have only minor effects on complement homeostasis, the combined effects of variants in multiple complement genes, referred to as the "complotype", can have major effects. In some diseases, the complotype highlights specific parts of the complement pathway involved in disease, thereby pointing towards a mechanism; however, this is not the case with AD. Here we review the complement GWAS hits; CR1 encoding complement receptor 1 (CR1), CLU encoding clusterin, and a suggestive association of C1S encoding the enzyme C1s, and discuss difficulties in attributing the AD association in these genes to complement function. A better understanding of complement genetics in AD might facilitate predictive genetic screening tests and enable the development of simple diagnostic tools and guide the future use of anti-complement drugs, of which several are currently in development for central nervous system disorders.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/imunologia , Ativação do Complemento/genética , Encéfalo/patologia , Clusterina/genética , Ativação do Complemento/imunologia , Complemento C1s/genética , Proteínas do Sistema Complemento/genética , Predisposição Genética para Doença/genética , Estudo de Associação Genômica Ampla/métodos , Humanos , Polimorfismo de Nucleotídeo Único/genética , Receptores de Complemento 3b/genética
5.
Neurologia (Engl Ed) ; 36(9): 681-691, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34752346

RESUMO

INTRODUCTION: Alzheimer disease risk polymorphisms have been studied in patients with dementia, but have not yet been explored in mild cognitive impairment (MCI) in our population; nor have they been addressed in relation to cognitive variables, which can be predictive biomarkers of disease. OBJECTIVE: To evaluate cognitive performance and presence of polymorphisms of the genes SORL1(rs11218304), PVRL2(rs6859), CR1(rs6656401), TOMM40(rs2075650), APOE (isoforms ε2, ε3, ε4), PICALM(rs3851179), GWAS_14q(rs11622883), BIN1(rs744373), and CLU(rs227959 and rs11136000) in patients with MCI and healthy individuals. METHODOLOGY: We performed a cross-sectional, exploratory, descriptive study of a prospective cohort of participants selected by non-probabilistic sampling, evaluated with neurological, neuropsychological, and genetic testing, and classified as cognitively healthy individuals and patients with MCI. Cognition was evaluated with the Neuronorma battery and analysed in relation to the polymorphic variants by means of measures of central tendency, confidence intervals, and nonparametric statistics. RESULTS: We found differences in performance in language and memory tasks between carriers and non-carriers of BIN1, CLU, and CR1 variants and a trend towards poor cognitive performance for PICALM, GWAS_14q, SORL1, and PVRL2 variants; the APOE and TOMM40 variants were not associated with poor cognitive performance. DISCUSSION: Differences in cognitive performance associated with these polymorphic variants may suggest that the mechanisms regulating these genes could have an effect on cognition in the absence of dementia; however, this study was exploratory and hypotheses based on these results must be explored in larger samples.


Assuntos
Disfunção Cognitiva , Proteínas Monoméricas de Montagem de Clatrina , Proteínas Adaptadoras de Transdução de Sinal , Apolipoproteínas E/genética , Clusterina/genética , Cognição , Disfunção Cognitiva/genética , Estudos Transversais , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Proteínas Relacionadas a Receptor de LDL , Proteínas de Membrana Transportadoras/genética , Proteínas do Complexo de Importação de Proteína Precursora Mitocondrial , Proteínas Monoméricas de Montagem de Clatrina/genética , Proteínas Nucleares , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Receptores de Complemento 3b/genética , Proteínas Supressoras de Tumor
6.
Commun Biol ; 4(1): 401, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767430

RESUMO

Vitamin D deficiency remains a global concern. This 'sunshine' vitamin is converted through a multistep process to active 1,25-dihydroxyvitamin D3 (1,25D), the final step of which can occur in macrophages. Here we demonstrate a role for vitamin D in innate immunity. The expression of the complement receptor immunoglobulin (CRIg), which plays an important role in innate immunity, is upregulated by 1,25D in human macrophages. Monocytes cultured in 1,25D differentiated into macrophages displaying increased CRIg mRNA, protein and cell surface expression but not in classical complement receptors, CR3 and CR4. This was associated with increases in phagocytosis of complement opsonised Staphylococcus aureus and Candida albicans. Treating macrophages with 1,25D for 24 h also increases CRIg expression. While treating macrophages with 25-hydroxyvitamin D3 does not increase CRIg expression, added together with the toll like receptor 2 agonist, triacylated lipopeptide, Pam3CSK4, which promotes the conversion of 25-hydroxyvitamin D3 to 1,25D, leads to an increase in CRIg expression and increases in CYP27B1 mRNA. These findings suggest that macrophages harbour a vitamin D-primed innate defence mechanism, involving CRIg.


Assuntos
Calcitriol/metabolismo , Imunidade Inata/fisiologia , Imunoglobulinas/metabolismo , Macrófagos/metabolismo , Receptores de Complemento 3b/genética , Regulação para Cima/imunologia , Receptores de Complemento 3b/metabolismo
7.
Hum Genomics ; 15(1): 9, 2021 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-33516273

RESUMO

Genome-wide association studies (GWAS) have identified several susceptibility loci of Alzheimer's disease (AD), which were mainly located in noncoding regions of the genome. Meanwhile, the putative biological mechanisms underlying AD susceptibility loci were still unclear. At present, identifying the functional variants of AD pathogenesis remains a major challenge. Herein, we first used summary data-based Mendelian randomization (SMR) with AD GWAS summary and expression quantitative trait loci (eQTL) data to identify variants who affects expression levels of nearby genes and contributed to the risk of AD. Using the SMR integrative analysis, we totally identified 14 SNPs significantly affected the expression level of 16 nearby genes in blood or brain tissues and contributed to the AD risk. Then, to confirm the results, we replicated the GWAS and eQTL results across multiple samples. Totally, four risk SNP (rs11682128, rs601945, rs3935067, and rs679515) were validated to be associated with AD and affected the expression level of nearby genes (BIN1, HLA-DRA, EPHA1-AS1, and CR1). Besides, our differential expression analysis showed that the BIN1 gene was significantly downregulated in the hippocampus (P = 2.0 × 10-3) and survived after multiple comparisons. These convergent lines of evidence suggest that the BIN1 gene identified by SMR has potential roles in the pathogenesis of AD. Further investigation of the roles of the BIN1 gene in the pathogenesis of AD is warranted.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Predisposição Genética para Doença , Proteínas Nucleares/genética , Locos de Características Quantitativas/genética , Proteínas Supressoras de Tumor/genética , Doença de Alzheimer/patologia , Feminino , Regulação da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Cadeias alfa de HLA-DR/genética , Humanos , Masculino , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único/genética , RNA Longo não Codificante/genética , Receptor EphA1/genética , Receptores de Complemento 3b/genética , Fatores de Risco
8.
BMC Genet ; 21(1): 101, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32907542

RESUMO

BACKGROUND: The complement cascade is increasingly implicated in development of a variety of diseases with strong immune contributions such as Alzheimer's disease and Systemic Lupus Erythematosus. Mouse models have been used to determine function of central components of the complement cascade such as C1q and C3. However, species differences in their gene structures mean that mice do not adequately replicate human complement regulators, including CR1 and CR2. Genetic variation in CR1 and CR2 have been implicated in modifying disease states but the mechanisms are not known. RESULTS: To decipher the roles of human CR1 and CR2 in health and disease, we engineered C57BL/6J (B6) mice to replace endogenous murine Cr2 with human complement receptors, CR1 and CR2 (B6.CR2CR1). CR1 has an array of allotypes in human populations and using traditional recombination methods (Flp-frt and Cre-loxP) two of the most common alleles (referred to here as CR1long and CR1short) can be replicated within this mouse model, along with a CR1 knockout allele (CR1KO). Transcriptional profiling of spleens and brains identified genes and pathways differentially expressed between mice homozygous for either CR1long, CR1short or CR1KO. Gene set enrichment analysis predicts hematopoietic cell number and cell infiltration are modulated by CR1long, but not CR1short or CR1KO. CONCLUSION: The B6.CR2CR1 mouse model provides a novel tool for determining the relationship between human-relevant CR1 alleles and disease.


Assuntos
Receptores de Complemento 3b/genética , Receptores de Complemento 3d/genética , Alelos , Animais , Modelos Animais de Doenças , Feminino , Homozigoto , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Regiões Promotoras Genéticas , Transcriptoma
9.
Clin Exp Immunol ; 197(3): 329-340, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31009057

RESUMO

Type 1 diabetes mellitus is an autoimmune metabolic disorder characterized by chronic hyperglycemia, the presence of autoreactive T and B cells and autoantibodies against self-antigens. A membrane-bound enzyme on the pancreatic beta-cells, glutamic acid decarboxylase 65 (GAD65), is one of the main autoantigens in type 1 diabetes. Autoantibodies against GAD65 are potentially involved in beta-cell destruction and decline of pancreatic functions. The human complement receptor type 1 (CD35) on B and T lymphocytes has a suppressive activity on these cells. We hypothesized that it may be possible to eliminate GAD65-specific B cells from type 1 diabetes patients by using chimeric molecules, containing an anti-CD35 antibody, coupled to peptides resembling GAD65 B/T epitopes. These molecules are expected to selectively bind the anti-GAD65 specific B cells by the co-cross-linking of the immunoglobulin receptor and CD35 and to deliver a suppressive signal. Two synthetic peptides derived from GAD65 protein (GAD65 epitopes) and anti-CD35 monoclonal antibody were used for the construction of two chimeras. The immunomodulatory activity of the engineered antibodies was tested in vitro using peripheral blood mononuclear cells (PBMCs) from type 1 diabetes patients. A reduction in the number of anti-GAD65 IgG antibody-secreting plasma cells and increased percentage of apoptotic B lymphocytes was observed after treatment of these PBMCs with the engineered antibodies. The constructed chimeric molecules are able to selectively modulate the activity of GAD65-specific B lymphocytes and the production of anti-GAD65 IgG autoantibodies by co-cross-linking of the inhibitory CD35 and the B cell antigen receptor (BCR). This treatment presents a possible way to alter the autoimmune nature of these cells.


Assuntos
Anticorpos Monoclonais , Epitopos de Linfócito B , Glutamato Descarboxilase , Peptídeos , Engenharia de Proteínas , Receptores de Complemento 3b , Adulto , Anticorpos Monoclonais/química , Anticorpos Monoclonais/genética , Anticorpos Monoclonais/farmacologia , Autoanticorpos/genética , Autoanticorpos/imunologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Epitopos de Linfócito B/química , Epitopos de Linfócito B/genética , Epitopos de Linfócito B/farmacologia , Feminino , Glutamato Descarboxilase/química , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/farmacologia , Humanos , Masculino , Peptídeos/química , Peptídeos/genética , Peptídeos/farmacologia , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Complemento 3b/antagonistas & inibidores , Receptores de Complemento 3b/genética , Receptores de Complemento 3b/imunologia , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia
10.
Gene ; 688: 107-118, 2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30529247

RESUMO

BACKGROUND: Several investigators have reported that complement receptor 1 (CR1) likely play a role in the pathogenesis of tumors, autoimmune and inflammatory diseases. However, the association of genetic polymorphisms of CR1 with risk of hepatitis B virus (HBV)-related liver disease remains unexplored. METHODS: In a case-control study of 399 HBV-related liver disease patients and 227 healthy controls, we genotyped two SNPs in CR1 (rs3811381 and rs2274567) and assessed their associations with risk of HBV-related liver disease. RESULTS: No significant differences were observed in the frequency distribution of genotypes or alleles between CR1 rs3811381 and rs2274567 polymorphisms in patients and controls. However, stratification analysis indicated that these two CR1 polymorphisms may contribute to the risk of HBV- hepatocellular carcinoma (HCC) and chronic hepatitis B (CHB) in subgroups of males, alcohol drinkers and nonsmokers. Further, our results showed that the rs3811381 polymorphism may contribute to HBV-HCC risk in subgroups of older and younger subjects, while the G allele, AG and the combined AG + GG genotypes of rs2274567 may be risk factors for HBV-HCC in younger subjects. In addition, our results indicated that subjects who carried the rs3811381 G allele and the rs2274567 AG genotype were at decreased risk of HBV- liver cirrhosis (LC) in subgroups of females. CONCLUSIONS: Our results support the hypothesis that the CR1 gene rs3811381 and rs2274567 polymorphisms may contribute to HBV-HCC and HBV-CHB risk, particularly in subgroups of males, alcohol drinkers, nonsmokers, while these two CR1 polymorphisms were found to associate with decreased risk of HBV-LC, particularly in females. Further validation of these results is warranted.


Assuntos
Predisposição Genética para Doença/genética , Hepatite B Crônica/genética , Hepatopatias/genética , Hepatopatias/virologia , Fígado/virologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Complemento 3b/genética , Adulto , Alelos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Feminino , Frequência do Gene/genética , Genótipo , Vírus da Hepatite B/patogenicidade , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade
11.
J Mol Neurosci ; 64(3): 471-477, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29504051

RESUMO

Genome-wide association studies (GWAS) have associated several genetic variants with late-onset Alzheimer's disease (LOAD), a neurodegenerative disease. Among those, rs3764650 ABCA7, rs6656401 CR1, and rs744373 BIN1 were associated as risk factors for LOAD, while rs11136000 CLU and rs610932 MS4A6A were protective. Recently, several case-control studies have investigated the association of these polymorphisms with AD. However, not all meta-analyses analyzed these variants across different ethnic groups. Therefore, we performed an updated meta-analysis of rs3764650 ABCA7, rs6656401 CR1, rs744373 BIN1, rs11136000 CLU, and rs610932 MS4A6A variants associated with LOAD, considering different ethnic populations. We utilized samples from 38 articles, comprising a total of 24,771 patients and 35,324 controls obtained through the PubMed database. Odds ratios (ORs) with 95% confidence intervals (CI) for polymorphisms were calculated by allelic comparison as an additive genetic model. We validated the risk for LOAD with BIN1 (rs744373), CR1 (rs6656401), and ABCA7 (rs376465), as well as the protective association for MS4A6A (rs610932) and CLU (rs11136000) variants.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Clusterina/genética , Proteínas de Membrana/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Receptores de Complemento 3b/genética , Proteínas Supressoras de Tumor/genética , Humanos
12.
Front Immunol ; 9: 453, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29563915

RESUMO

Complement receptor type 1 (CR1) is a multi modular membrane receptor composed of 30 homologous complement control protein modules (CCP) organized in four different functional regions called long homologous repeats (LHR A, B, C, and D). CR1 is a receptor for complement-opsonins C3b and C4b and specifically interacts through pairs of CCP modules located in LHR A, B, and C. Defense collagens such as mannose-binding lectin (MBL), ficolin-2, and C1q also act as opsonins and are involved in immune clearance through binding to the LHR-D region of CR1. Our previous results using deletion variants of CR1 mapped the interaction site for MBL and ficolin-2 on CCP24-25. The present work aimed at deciphering the interaction of C1q with CR1 using new CR1 variants concentrated around CCP24-25. CR1 bimodular fragment CCP24-25 and CR1 CCP22-30 deleted from CCP24-25 produced in eukaryotic cells enabled to highlight that the interaction site for both MBL and C1q is located on the same pair of modules CCP24-25. C1q binding to CR1 shares with MBL a main common interaction site on the collagen stalks but also subsidiary sites most probably located on C1q globular heads, contrarily to MBL.


Assuntos
Complemento C1q/química , Lectina de Ligação a Manose/química , Peptídeos/química , Receptores de Complemento 3b/química , Complemento C1q/genética , Complemento C1q/imunologia , Humanos , Lectinas/química , Lectinas/genética , Lectinas/imunologia , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/imunologia , Peptídeos/genética , Peptídeos/imunologia , Ligação Proteica , Domínios Proteicos , Estrutura Secundária de Proteína , Receptores de Complemento 3b/genética , Receptores de Complemento 3b/imunologia , Ficolinas
13.
Adv Neurobiol ; 15: 31-53, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28674977

RESUMO

Alzheimer's disease is the most common form of dementia accounting for 50-60% of all dementia cases. This chapter briefly reviews the history of Alzheimer's disease and provides an overview of the clinical syndromes associated with Alzheimer pathology and their associated neuroimaging findings. This chapter also reviews the neuropathology and genetics of Alzheimer's disease and concludes by discussing current work undertaken to identify suitable in vivo biomarkers for the disease.


Assuntos
Doença de Alzheimer/fisiopatologia , Afasia/fisiopatologia , Encéfalo/fisiopatologia , Cognição , Memória , Transportadores de Cassetes de Ligação de ATP/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Compostos de Anilina , Apolipoproteína E4/genética , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Antígenos HLA/genética , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Proteínas Nucleares/genética , Tomografia por Emissão de Pósitrons , Presenilinas/genética , Receptores de Complemento 3b/genética , Tiazóis , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Proteínas Supressoras de Tumor/genética
14.
Mol Biol Rep ; 44(2): 227-231, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28316001

RESUMO

Alzheimer's disease (AD) is the most common type of dementia, with a prevalence that is rising every year. AD is associated with type 2 diabetes mellitus (T2DM) and insulin resistance, and is therefore sometimes called "type 3 diabetes mellitus". The aim of this study was to examine whether the variants of some candidate genes involved in the development of AD, namely BIN1 (rs744373), CLU (rs11136000), CR1 (rs3818361), and PICALM (rs3851179), are related to several disorders of glucose metabolism-gestational diabetes (GDM), T2DM and impaired glucose tolerance (IGT). Our study included 550 women with former GDM and 717 control women, 392 patients with T2DM and 180 non-diabetic controls, and 117 patients with IGT and 630 controls with normal glucose tolerance. Genotyping analysis was performed using specially-designed TaqMan assays. No significant associations of the genetic variants rs744373 in BIN1, rs11136000 in CLU, or rs3818361 in CR1 were found with GDM, T2DM or IGT, but rs3851179 in PICALM was associated with an increased risk of GDM. The frequency of the AD risk-associated C allele was significantly higher in the GDM group compared to controls: OR 1.21; 95% CI (1.03-1.44). This finding was not apparent in T2DM and IGT; conversely, the C allele of the PICALM SNP was protective for IGT: OR 0.67; 95% CI (0.51-0.89). This study demonstrates an association between PICALM rs3851179 and GDM as well as IGT. However, elucidation of the possible role of this gene in the pathogenesis of GDM requires further independent studies.


Assuntos
Doença de Alzheimer/genética , Diabetes Gestacional/genética , Intolerância à Glucose/genética , Proteínas Monoméricas de Montagem de Clatrina/genética , Proteínas Adaptadoras de Transdução de Sinal/sangue , Proteínas Adaptadoras de Transdução de Sinal/genética , Adulto , Idoso , Alelos , Doença de Alzheimer/complicações , Clusterina/sangue , Clusterina/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Gestacional/metabolismo , Feminino , Frequência do Gene , Estudos de Associação Genética/métodos , Predisposição Genética para Doença , Variação Genética , Intolerância à Glucose/metabolismo , Humanos , Pessoa de Meia-Idade , Proteínas Monoméricas de Montagem de Clatrina/sangue , Proteínas Nucleares/sangue , Proteínas Nucleares/genética , Razão de Chances , Polimorfismo de Nucleotídeo Único/genética , Gravidez , Receptores de Complemento 3b/sangue , Receptores de Complemento 3b/genética , Fatores de Risco , Proteínas Supressoras de Tumor/sangue , Proteínas Supressoras de Tumor/genética , População Branca/genética
15.
Immunobiology ; 222(2): 363-371, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27644115

RESUMO

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hemolytic anemia characterized by complement-mediated intravascular hemolysis that is effectively treated with eculizumab. However, treatment responses are reported heterogeneous with some patients presenting residual hemolysis and requiring RBC transfusions. Recent reports have shown that both extravascular hemolysis and incomplete C5 blockade can explain these suboptimal hematological responses. Here we have tested our eculizumab-treated PNH patients (n=12) for signs of hemolysis and assessed complement biomarkers. Patients were also genotyped for complement receptor 1 (CR1, CD35) and C5 polymorphisms and evaluated for free eculizumab in plasma. We report that 10 patients (83%) present parameters suggesting persistent hemolysis, although they did not require additional transfusions. Seven of them (58%) become direct Coombs-test positive as a consequence of treatment, including all patients carrying the low-expression CR1-L allele. CH50 and sC5b-9 assays demonstrate that the persistent low-level hemolysis identified in our treated patients is not a consequence of incomplete C5 blockade, supporting that this hemolysis, as has been suggested previously, results from the extravascular removal of C3 opsonized PNH erythrocytes. We also show that continuous alternative pathway activation in eculizumab-treated individuals carrying the CR1-L allele results in abnormally decreased levels of C3 in plasma that could, potentially, increase their susceptibility to bacterial infections. Finally, we encourage a routine evaluation of free eculizumab levels and terminal pathway activity to personalize eculizumab administration.


Assuntos
Proteínas do Sistema Complemento/imunologia , Hemoglobinúria Paroxística/sangue , Hemoglobinúria Paroxística/imunologia , Hemólise/imunologia , Anticorpos Monoclonais Humanizados/uso terapêutico , Criança , Pré-Escolar , Ativação do Complemento/efeitos dos fármacos , Ativação do Complemento/imunologia , Complemento C3/imunologia , Complemento C5/imunologia , Inativadores do Complemento/uso terapêutico , Citotoxicidade Imunológica , Feminino , Predisposição Genética para Doença , Variação Genética , Genótipo , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/tratamento farmacológico , Humanos , Lactente , Masculino , Receptores de Complemento 3b/genética , Receptores de Complemento 3b/metabolismo , Resultado do Tratamento
16.
Neurology ; 87(5): 489-96, 2016 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-27371493

RESUMO

OBJECTIVE: To investigate the associations of previously reported Alzheimer disease (AD) dementia genomic variants with common neuropathologies. METHODS: This is a postmortem study including 1,017 autopsied participants from 2 clinicopathologic cohorts. Analyses focused on 22 genomic variants associated with AD dementia in large-scale case-control genome-wide association study (GWAS) meta-analyses. The neuropathologic traits of interest were a pathologic diagnosis of AD according to NIA-Reagan criteria, macroscopic and microscopic infarcts, Lewy bodies (LB), and hippocampal sclerosis. For each variant, multiple logistic regression was used to investigate its association with neuropathologic traits, adjusting for age, sex, and subpopulation structure. We also conducted power analyses to estimate the sample sizes required to detect genome-wide significance (p < 5 × 10(-8)) for pathologic AD for all variants. RESULTS: APOE ε4 allele was associated with greater odds of pathologic AD (odds ratio [OR] 3.82, 95% confidence interval [CI] 2.67-5.46, p = 1.9 × 10(-13)), while ε2 allele was associated with lower odds of pathologic AD (OR 0.42, 95% CI 0.30-0.61, p = 3.1 × 10(-6)). Four additional genomic variants including rs6656401 (CR1), rs1476679 (ZCWPW1), rs35349669 (INPP5D), and rs17125944 (FERMT2) had p values less than 0.05. Remarkably, half of the previously reported AD dementia variants are not likely to be detected for association with pathologic AD with a sample size in excess of the largest GWAS meta-analyses of AD dementia. CONCLUSIONS: Many recently discovered genomic variants for AD dementia are not associated with the pathology of AD. Some genomic variants for AD dementia appear to be associated with other common neuropathologies.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Infarto Cerebral/patologia , Variação Genética , Genoma Humano/genética , Hipocampo/patologia , Corpos de Lewy/patologia , Idoso de 80 Anos ou mais , Alelos , Apolipoproteínas E/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Modelos Logísticos , Masculino , Proteínas de Membrana/genética , Proteínas de Neoplasias/genética , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Receptores de Complemento 3b/genética , Dedos de Zinco/genética
17.
Medicine (Baltimore) ; 94(40): e1681, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26448013

RESUMO

Malaria is highly endemic in Yunnan Province, China, with the incidence of malaria being highest along the Sino-Burmese border. The aim of our study was to determine whether genetic polymorphisms are associated with the prevalence of malaria among Chinese residents of the Sino-Burmese border region. Fourteen otherwise healthy people with glucose-6-phosphate dehydrogenase (G6PD) deficiency, 50 malaria patients, and 67 healthy control subjects were included in our cross-sectional study. We analyzed the frequency of the G3093T and T520C single-nucleotide polymorphisms (SNPs) of CR1. Logistic regression was used to calculate the prevalence odds ratio (POR) and 95% confidence interval (CI) of malaria for the T520C SNP of CR1 and SNPs of G6PD, IL-4, IL-4R, IL-1A, NOS, CD40LG, TNF, and LUC7L. The frequency of the 3093T/3093T genotype of CR1 in the malaria group (0.16) was significantly higher than that in the control group (0.045, P < 0.05), and significantly lower than that in the G6PD deficiency group (0.43, P < 0.01). The frequency of the 520T/520T genotype of CR1 was significantly higher in the malaria patients (0.78) than that in the control group (0.67, P < 0.05) and G6PD-deficiency group (0.36, P < 0.05). The T allele of the T520C variant of CR1 was significantly associated with the prevalence of malaria (POR: 1.460; 95% CI: 0.703-3.034). Polymorphisms of G6PD did not significantly influence the prevalence malaria (P > 0.05). A GTGTGTC haplotype consisting of IL-1A (rs17561), IL-4 (rs2243250), TNF (rs1800750), IL-4R (rs1805015), NOS (rs8078340), CD40LG (rs1126535), and LUC7L (rs1211375) was significantly associated with the prevalence of malaria (POR: 1.822, 95% CI: 0.998-3.324). The 3093G/3093G and 520T/520T genotypes are the predominant genetic variants of CR1 among Chinese residents near the Sino-Burmese border, and the T allele of T520C is associated with the prevalence of malaria in this region. Although G6PD deficiency does not protect against malaria, it may diminish the association between malaria and the CR1 polymorphisms in this population. The GTGTGTC haplotype is also associated with the prevalence of malaria in this region.


Assuntos
Citocinas/genética , Deficiência de Glucosefosfato Desidrogenase/genética , Malária/epidemiologia , Óxido Nítrico Sintase/genética , Proteínas de Ligação a RNA/genética , Receptores de Complemento 3b/genética , Adulto , Alelos , China/epidemiologia , Estudos Transversais , Feminino , Genótipo , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Humanos , Incidência , Interleucinas/genética , Malária/genética , Masculino , Mianmar/epidemiologia , Razão de Chances , Reação em Cadeia da Polimerase , Polimorfismo de Nucleotídeo Único , Prevalência , Fator de Necrose Tumoral alfa/genética
18.
Mol Psychiatry ; 20(10): 1173-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26033242

RESUMO

Several genetic polymorphisms have been associated with Late Onset Alzheimer's Disease (LOAD), but there has been limited evidence on whether these polymorphisms predict intermediary stage outcomes such as cognitive changes in prospective community-based studies. Our aim was to evaluate whether polymorphisms previously established as predictors of LOAD also predict worse cognitive function and accelerated decline across multiple cognitive domains. We analyzed data from the 3C-Dijon study, in which 4931 respondents aged 65+ were examined up to 5 times over 10 years with a neuropsychological assessment. We evaluated the associations of polymorphisms in APOE, CR1, BIN1, CLU, PICALM, ABCA7, MS4A6A, CD33, MS4A4E and CD2AP with level and change in 5 neuropsychological tests, assuming a dominant effect model. To optimize measurement, we used a mixed regression model with a latent process for each cognitive domain: global cognition (Mini Mental State Examination); verbal fluency (Isaac's Set Test); visual memory (Benton Visual Retention Test); information processing (Trail Making Test B) and literacy (National Adult Reading Test). APOE was associated with accelerated decline in global cognition and verbal fluency. Only two non-APOE genetic polymorphisms were associated with cognitive decline: CR1 was associated with rate of change in verbal fluency and BIN1 was associated with rate of change in global cognition. In a large prospective population-based study of dementia-free individuals, only a few cognitive domains were associated with established LOAD risk alleles. The most consistent associations were for global cognition and verbal fluency.


Assuntos
Doença de Alzheimer/genética , Transtornos Cognitivos/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo , Transtornos Cognitivos/psicologia , Estudos de Coortes , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Estudos Longitudinais , Masculino , Memória , Proteínas Nucleares/genética , Polimorfismo Genético , Estudos Prospectivos , Receptores de Complemento 3b/genética , Fatores de Risco , Proteínas Supressoras de Tumor/genética
19.
Cell Immunol ; 296(2): 133-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25959608

RESUMO

Tumor necrosis factor (TNF) is a key cytokine in rheumatoid arthritis (RA) pathogenesis, as underscored by the clinical effectiveness of TNF antagonists. While several of TNF's key targets in RA are well understood, its many pleiotropic effects remain to be elucidated. TNF-transgenic mice develop inflammatory-erosive arthritis associated with disruption of draining lymph node histology and function, and accumulation of B cells with unique phenotypic and functional features consistent with contribution to pathogenesis (B cells in inflamed nodes, Bin). Bin cell induction depends on the inflamed microenvironment, but the specific signals are unknown. Using anti-TNF treatment and TNF-receptor-deficient mice, here we show that Bin cells are induced and maintained independently of B cell-intrinsic TNF signals.


Assuntos
Anticorpos/farmacologia , Artrite Experimental/imunologia , Linfócitos B/imunologia , Linfonodos/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Transferência Adotiva , Animais , Antígenos CD1d/genética , Antígenos CD1d/imunologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/genética , Artrite Experimental/patologia , Artrite Reumatoide/genética , Artrite Reumatoide/imunologia , Artrite Reumatoide/patologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Linfócitos B/transplante , Microambiente Celular/imunologia , Expressão Gênica , Humanos , Imunofenotipagem , Linfonodos/efeitos dos fármacos , Linfonodos/patologia , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores de Complemento 3b/genética , Receptores de Complemento 3b/imunologia , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/imunologia , Receptores de IgE/genética , Receptores de IgE/imunologia , Receptores Tipo I de Fatores de Necrose Tumoral/deficiência , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Receptores Tipo I de Fatores de Necrose Tumoral/imunologia , Receptores Tipo II do Fator de Necrose Tumoral/deficiência , Receptores Tipo II do Fator de Necrose Tumoral/genética , Receptores Tipo II do Fator de Necrose Tumoral/imunologia , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia
20.
J Mol Neurosci ; 54(4): 780-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25022885

RESUMO

Alzheimer's disease (AD) is the most common form of dementia in older population. Growing evidence of genetic background that predisposes individuals to AD has been reported as the risk factors in recent years. The Department of Medical Genetics and the Immunology Research Centre investigated the distribution of 11 polymorphisms in 160 patients with late onset AD (LOAD) and in 163 healthy controls, using the sequencing technique. All participants were of Turkish Azeri ethnicity. We compared allele and genotype frequencies between the LOAD patients and control subjects using a chi-square or Fisher's exact test. Alleles and genotypes of APOE, PICALM rs3851179 and rs541458, and the BIN1 gene rs744373 polymorphism were significantly different between LOAD and control groups. The frequencies of the other investigated alleles were similar in the two groups. We also analyzed the association of BIN1, CR1 and PICALM SNPs with LOAD in subgroups stratified by the presence or absence of the APOE ε4 allele. After adjusting for APOE, statistical analysis revealed that the association with PICALM rs541458 and BIN1 rs744373 were only significant among subjects without the APOE ε4 allele.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Doença de Alzheimer/genética , Apolipoproteínas E/genética , Proteínas Monoméricas de Montagem de Clatrina/genética , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único , Receptores de Complemento 3b/genética , Proteínas Supressoras de Tumor/genética , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA