RESUMO
The aim of this study was to develop an assay to analyze the serum profile of Mannose-binding lectin (MBL) through a simple and "in-house" method (called "dot-N-man"). Furthermore, the study attempted to associate molecular masses of MBL to the profile of MBL gene polymorphisms in patients with hepatitis C. Heterogeneity in molecular masses of MBL is due to the impairment of oligomers formation, which is linked to genetic polymorphisms in the MBL gene. Individuals with AA genotype (wild-type) produce high-molecular-mass proteins, whereas AO and OO individuals produce intermediate and low-molecular-mass proteins, respectively. Sera of thirty patients carrying the hepatitis C virus (HCV) were investigated using MBL binding assay with mannan-coated nitrocellulose (dot-N-man). Purified MBL was evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. Dot-N-Man assay yielded MBL with molecular masses ranging between 55 and 320â¯kDa, comparable to low and high molecular mass forms of MBL. Nonreducing SDS-PAGE showed high molecular mass bands in all AA individuals while bands of 270 and 205â¯kDa were observed in sera for a number of patients with AO and OO genotypes, respectively. Immunoblotting confirmed the MBL samples obtained from the dot-N-man. These results provide new insights to understand the MBL molecular forms profile in patients infected with HCV- which could be useful in future investigations on the influence of the MBL structure/genotype on both the progression of infection and the response to hepatitis C therapy.
Assuntos
Hepacivirus/imunologia , Hepatite C , Immunoblotting/métodos , Lectina de Ligação a Manose , Polimorfismo Genético , Colódio/química , Feminino , Hepatite C/genética , Hepatite C/imunologia , Humanos , Masculino , Mananas/química , Lectina de Ligação a Manose/genética , Lectina de Ligação a Manose/imunologiaRESUMO
The hepatic damage caused by hepatitis C virus (HCV) infection is associated with the host immune response and viral regulatory factors. Catalase (CAT) and glutathione peroxidase 1 (GPX1) are antioxidant enzymes located in the peroxisomes and mitochondria, respectively, and are responsible for the control of intracellular hydrogen peroxide levels. Polymorphisms in CAT (C-262T) and GPX1 (Pro198Leu) are correlated with serum levels and enzyme activity. This study aimed to investigate the association of genetic polymorphisms of CAT C-262T (rs1001179) and GPX1 Pro198Leu (rs1050450) with different stages of liver fibrosis and development of hepatocellular carcinoma (HCC). This study included 445 patients with chronic hepatitis C, of whom 139 patients had mild fibrosis (F0-F1), 200 had moderate/severe fibrosis (F2-F4), and 106 had HCC. Genotyping of SNPs was performed by real-time PCR using TaqMan probes. The Pro/Pro genotype of GPX1 was significantly associated with fibrosis severity, HCC, Child Pugh score, and BCLC staging. Additionally, patients carrying both CT+TT genotypes in the CAT gene and the Pro/Pro genotype in the GPX1 gene had higher risk for developing moderate/severe fibrosis or HCC (p = 0.009, OR 2.40 and p = 0.002, OR 3.56, respectively). CAT and GPX1 polymorphisms may be implicated in the severity of liver fibrosis and HCC caused by HCV.
Assuntos
Catalase/genética , Glutationa Peroxidase/genética , Hepatite C Crônica/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Alelos , Carcinoma Hepatocelular/genética , Feminino , Frequência do Gene , Genótipo , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Glutationa Peroxidase GPX1RESUMO
Celiac disease (CD) is an autoimmune disease of the small bowel characterized by a strong genetic association with HLA - DQ2 and DQ8. Gluten is the etiological factor and the tissue enzyme transglutaminase (TGase) is its autoantigen. CD is associated with several autoimmune diseases such as type 1 diabetes, systemic lupus erythematous, rheumatoid arthritis, Sjögrens syndrome and autoimmune thyroid diseases. The aim of this study was to investigate the occurrence of serum IgA anti-endomysial and anti-human TGase antibodies in individuals with positive anti-thyroid antibody (ATA). The concordance between these two tests was also evaluated. Anti-endomysial antibodies were positive in 10 out of 456 (2.2%) and anti-human TGase were positive in 14 of 454 (3.1%) individuals with positive ATA. In control subjects they were positive in 1 of 197 (0.5%) and 2 of 198 (1%) for anti-endomysial and anti-human tissue TGase antibodies, respectively. The odds ratio (OR) for the anti-endomysial antibodies was 4.42 and for the anti-human TGase 3.12 in individuals with ATA when compared with controls. An elevated concordance index (k= 0.84) was observed between anti-endomisyal antibodies and anti-human TGase. We conclude that the determination of anti-TGase antibodies is a good test for DC screening.
Assuntos
Doenças Autoimunes/complicações , Doença Celíaca/diagnóstico , Imunoglobulina A/sangue , Doenças da Glândula Tireoide/complicações , Adolescente , Adulto , Fatores Etários , Idoso , Doenças Autoimunes/imunologia , Biomarcadores/sangue , Estudos de Casos e Controles , Doença Celíaca/complicações , Doença Celíaca/imunologia , Criança , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Doenças da Glândula Tireoide/imunologia , Transglutaminases/imunologiaRESUMO
Doença celíaca (DC) é uma doença autoimune do intestino delgado com importante associação com HLA-DQ2 e DQ8. Tem o glúten como fator etiológico e a enzima transglutaminase (TGase) tecidual como autoantígeno. A DC é associada a outras doenças autoimunes como diabetes mellitus tipo 1, lupus eritematoso sistêmico, artrite reumatóide, síndrome de Sjõgren e doenças autoimunes da tireóide. O objetivo deste estudo foi investigar a ocorrência de anticorpos séricos da classe IgA anti-endomísio e anti-TGase tecidual humana em indivíduos com anticorpo anti-tireoidiano (AAT) positivo. Foi também pesquisada a concordância destes dois marcadores. Anticorpos anti-endomísio foram positivos em 10 de 456 (2,2 por cento) e anti-TGase tecidual foi positiva em 14 de 454 (3,1 por cento) dos indivíduos com AAT positivo. No grupo controle, 1 de 197 (0,5 por cento) e 2 de 198 (1 por cento) foram positivos para anticorpo anti-endomísio e anti-TGase tecidual humana, respectivamente. A chance de positividade dos anticorpos anti-endomísio foi de 4,42 e do anti-TGase tecidual humana 3,12 vezes maior nos indivíduos com positividade para AAT que nos controles. Um elevado índice de concordância (k= 0,84) foi obtido entre os testes para anticorpos anti-endomísio e anti-TGase. Os resultados obtidos neste trabalho não justificam uma triagem rotineira de DC em portadores de AAT. Concluímos que a pesquisa de anticorpos anti-TGase mostrou-se um teste útil para rastrear DC.