ABSTRACT
<p><b>OBJECTIVE</b>To investigate whether hepatitis B e antigen (HBeAg) can modulate the ability of dendritic cells (DCs) to produce inflammatory cytokines (IL-12/IL-6) upon stimulation in vitro.</p><p><b>METHODS</b>Purified adherent mononuclear cells isolated by Ficoll-hypaque density gradient centrifugation were cultured in complete medium containing granulocyte macrophage colony-stimulating factor plus interleukin (IL)-4 to generate immature (i)DCs. Microscopic analysis and flow cytometry were performed to define the phenotypic characteristics of the iDCs. Then, different concentrations (1, 2 and 5 mug/ml) of HBeAg were added to the culture medium and for 24 hrs of incubation. To induce iDCs' maturation, the various groups of cells were incubated for 24 hrs in differentiation culture with lipopolysaccharide (LPS). Effects on secreted inflammatory cytokines were determined by enzyme-linked immunosorbent assay of the cells' supernatants.</p><p><b>RESULTS</b>All concentrations of HBeAg led to significant reductions in IL-6 (all P less than 0.05). Similar significant reduction trends were seen for IL-12 at the HBeAg concentrations of 2 and 5 mug/ml (both P less than 0.05), but not at the 1 mug/ml concentration.</p><p><b>CONCLUSION</b>HBeAg may suppress the production of cytokines from DCs; this mechanism may contribute to the immune escape of HBV that supports persistent infection.</p>
Subject(s)
Humans , Cells, Cultured , Dendritic Cells , Allergy and Immunology , Metabolism , Hepatitis B e Antigens , Allergy and Immunology , Interleukin-12 , Metabolism , Interleukin-6 , Metabolism , LipopolysaccharidesABSTRACT
To investigate the relationship between uncoupling protein 2 (UCP2) expression and the damage caused by oxygen free radicals in acute liver failure rat models. Thirty-five male Sprague-Dawley rats were randomly divided into two groups: the control group (15 rats) and liver failure group (20 rats). The rats were injected intraperitoneally with thioacetamide (TAA) to induce models of acute liver failure. The levels of endotoxin (ET) were detected by double antibody sandwich enzyme-linked immunosorbent assay. The expression of liver UCP2 mRNA was detected by reverse transcription polymerase chain reaction. The superoxide dismutase (SOD) and malonaldehyde (MDA) were detected by spectrophotometry. The expression of UCP2 protein was observed by immunohistochemistry. The data of the two groups were compared using Mann-Whitney U test or ANOVA. The expression of UCP2 mRNA in liver failure group was higher as compared to the control group (P value is less than 0.01); the level of MDA and endotoxin of liver failure group were higher than that of the control group (P value is less than 0.01). SOD of the liver failure group was lower (P value is less than 0.01). There was a certain correlation between UCP2 mRNA expression and ET, SOD and MDA (r = 0.952, -0.667, 0. 634 respectively, P value is less than 0.05 or 0.01). UCP2 is highly expressed in the livers of liver failure rats. A certain correlation perhaps existed between the expression of UCP2 mRNA and the serous SOD, MDA and ET.
Subject(s)
Animals , Male , Rats , Endotoxins , Ion Channels , Metabolism , Liver , Metabolism , Liver Failure, Acute , Metabolism , Malondialdehyde , Mitochondrial Proteins , Metabolism , Rats, Sprague-Dawley , Reactive Oxygen Species , Superoxide Dismutase , Uncoupling Protein 2ABSTRACT
Objective In order to confirm the causes of viral meningitis outbreaks in Linhai county,Zhejiang province in 2004,and to analyze the relationship between hereditary variation and evolution of the pathogen.Methods 60 cerebrospinal fluid(CSF)specimens were collected from the suspected patients.Virus strains from the specimens were isolated with RD and Hep-2 cell lines,and identified through neutralization test.VP1 and VP4/VP2 genes of the isolated viruses were sequenced.Both phylogcnetic and homological trees were also constructed.Results 19 Echovirus type 30(E30)strains were isolated from 60 CSFs,in which E30 accounted for 31.7％.All of the complete VP1 genes in 4 sequenced virus isolates of E30 were composed of 876 nt,encoding 292 amino acids(aa).The identity of nucleotide and amino acid in VP1 gene were 82.4％-84.1％ and 93.5％-94.2％ between the 4 Linhai strains and the prototype strain Bastianni of E30,were 87.1％-99.9％ and 97.9％-100.0％ among the 4 virus strains of E30 from Linhai,respectively.The 4 Linhai strains could be classified into two classes.The diversity of nt and aa was minimal in the same class but obvious between the two classes,with the range of diversities as 12.9％ and 2.1％,respectively.The Linhai E30 strains had maximum similarity with the Zhejiang E30 strains in 2002-2003.The 4 Linhai strains of E30 in the phylogenetic tree of the VP1 gene were attributed into two branches of the G and H genotype,respectively.The G branch also included the E30 strains from Zhejiang,Jiangsu and Shangdong in 2003,while the H branch including E30 strains from Zhuji,Zhejiang in 2002.The phylogenetic tree of VP4/VP2 genes was similar to that of VP1 gene.Conclusion The outbreak of viral meningitis in Linhai county in 2004 was caused by the two classes of E30 strains with G and H genotype existed simultaneously.The Linhai E30 strains had maximum genetic relations to the Zhejiang,Jiangsu and Shangdong strains of E30.The H genotype was inferred to be a new variant strain,which was first isolated in Zhejiang province in 2002.