Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Expression of the hepatitis B virus S protein results in the formation of a lipoprotein particle, the hepatitis B surface antigen (HBsAg). Such particles, produced in Saccharomyces cerevisiae, bind to the cell surface of monocytes through interaction with the lipopolysaccharide binding protein and the lipopolysaccharide receptor, CD14. This attachment is suggested to depend on the presence of charged phospholipids in the particles. In addition, such particles interfere with the lipopolysaccharide and interleukin-2-induced activation of monocytes. In the present study, it is reported that of three Saccharomyces cerevisiae-derived HBsAg preparations, two have a reduced capacity to bind to monocytes. A correlation with a reduced potential to inhibit the lipopolysaccharide-induced activation of monocytes and an increased potential to stimulate HBsAg-specific T-cell proliferation is observed. Surprisingly, differences in phospholipid content that might explain these observations, were not detected.
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PMID:Saccharomyces cerevisiae-derived HBsAg preparations differ in their attachment to monocytes, immune-suppressive potential, and T-cell immunogenicity. 1279 12

Because it was observed recently that yeast-derived recombinant HBsAg interacts in a lipopolysaccharide binding protein-dependent manner with CD14 expressed on human monocytes, we investigated whether HBsAg influences the serum levels of sCD14, lipopolysaccharide binding protein and C-reactive protein in hepatitis B patients. Samples from acute and chronic hepatitis B and chronic hepatitis C patients were tested. All analytes were measured using commercial assays. HBsAg was quantified using an NIBSC titrated standard. sCD14 levels were higher in chronic hepatitis B and C patients than in healthy controls (P = 0.0006 and P < 0.0001, respectively). In chronic hepatitis B patients an inverse correlation was found between sCD14 and HBsAg (P = 0.0309). Lipopolysaccharide binding protein and C-reactive protein levels were higher in acute hepatitis B patients than in control subjects (P = 0.0217 and P = 0.0034, respectively). In chronic hepatitis B and C, sCD14 and C-reactive protein levels were higher in cirrhotic than in non-cirrhotic patients (P = 0.0072 and P = 0.0223, respectively).
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PMID:Soluble CD14 levels are increased and inversely correlated with the levels of hepatitis B surface antigen in chronic hepatitis B patients. 1293 92

Hepatitis B surface antigen, when produced in yeast (rHBsAg), is capable of binding to cells that express the lipopolysaccharide coreceptor CD14. This interaction is enhanced by a serum protein, the lipopolysaccharide binding protein (LBP). Here we report that most of the rHBsAg particles that attached to monocytes at 0 degrees C, were not endocytosed but were released back into the serum-containing binding buffer at 37 degrees C. Additionally, serum-dependent binding at 37 degrees C was weak when compared to the serum-dependent attachment at 0 degrees C. Pre-incubation at 37 degrees C of cells together with serum did not abolish binding of freshly added rHBsAg at 0 degrees C. However, pre-incubation of rHBsAg with serum at 37 degrees C reduced attachment to cells following incubation at 0 degrees C. Soluble CD14 and LBP, two serum proteins which can act as phospholipid transfer molecules, were shown not to be responsible for the inhibitory effect. Pre-incubation at 37 degrees C of rHBsAg in serum-free hepatoma cell line-conditioned media resulted in a pronounced reduction in subsequent binding to cells at 0 degrees C. These observations suggest that the temperature-dependent inhibitory effect is caused by serum factors that are probably secreted by hepatocytes.
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PMID:A temperature-dependent inhibitory activity of serum on the capacity of Saccharomyces cerevisiae-derived hepatitis B surface antigen to bind to monocytes. 1548 Aug 55

This study aimed to identify aberrantly methylated differentially methylated CpG sites (DMCs) and investigate their prognostic value in hepatocellular carcinoma (HCC). A total of 2,404 DMCs were selected from Gene Expression Omnibus (GEO) and validated by The Cancer Genome Atlas (TCGA). The TCGA cohort was divided into a training cohort and a validating cohort. First, the prognostic model based on six DMCs, including cg08351331, cg02910574, cg09947274, cg17589341, cg24652919, and cg26545968, was constructed based on the least absolute shrinkage and selection operator (LASSO) regression Cox analysis. The area under the curve (AUC) of the DMC-based model was 0.765 in the training cohort and 0.734 in the validating cohort. The accuracy of a model combining the DMC signature and American Joint Committee on Cancer (AJCC) stage, with an AUC of 0.795, was better than that of the DMCs or AJCC stage alone. Second, further analysis revealed that the methylation rate of cg08351331 was negatively associated with the expression of its relative gene, lipopolysaccharide-binding protein (LBP). Besides, the gene expression of LBP was significantly associated with poor overall survival in patients with hepatitis B virus (HBV) infection. Finally, these findings were confirmed by GSE57956 data and our own cohort. In conclusion, we established an accurate DMC-based prognostic model that could be combined with AJCC stage to improve the accuracy of prognostic prediction in HCC. Moreover, our preliminary data indicate that LBP may be a new key factor in HBV-induced HCC initiation through the regulation of its methylation.
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PMID:Identification of Aberrantly Methylated Differentially CpG Sites in Hepatocellular Carcinoma and Their Association With Patient Survival. 3279 65