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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An enzyme-linked immunosorbent assay (ELISA) was developed to detect the polymerized human serum albumin (pHSA) receptor on hepatitis B virus surface antigen (HBsAg) particles. The receptor values on particles from HBeAg-positive patients were significantly higher than those from anti-HBe-positive and HBeAg-, anti-HBe-negative patients. In patients' sera with moderate to high receptor values, there was significant correlation between the values obtained in the ELISA and serum DNA-polymerase activity (P less than 0.005), but not with HBeAg titer. During a 1-year follow-up of 47 HBeAg-positive patients with chronic hepatitis, termination of active viral replication, as evidenced by seroconversion from HBeAg to anti-HBe-positive, was observed in 1 of 26 with high initial receptor values, 2 of 12 with moderately high values and 6 of 9 with low receptor values. The results suggest that the ELISA described, which detects pHSA receptors on HBsAg particles, might be of value as a prognostic test in HBeAg-positive chronic hepatitis type B.
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PMID:Enzyme-linked immunosorbent assay for detection of receptors for polymerized human serum albumin on hepatitis B surface antigen particles. 609 78

A recombinant plasmid (pSVS dhfr) encoding the pre-S region and the S gene of human hepatitis B virus (HBV) and murine dihydrofolate reductase (DHFR) cDNA has been used for the transfection of Chinese hamster ovary (CHO) DHFR- cells. Selection of clones resistant to methotrexate has permitted amplification of HBV sequences and an increase in production of hepatitis B surface antigen (HBsAg). HBV-specific transcripts have been characterized. The HBsAg 22-nm particles contain a receptor for polymerized human serum albumin (pHSA) and elicit in animals the synthesis of antireceptor antibodies. This property is ascribed to a 34,000-dalton polypeptide in the particles, which is most likely encoded by the S gene and part of the pre-S region. Especially because the pHSA receptor is most abundantly present on the virion and because, in hepatitis B infection, the appearance of anti-pHSA receptor antibodies seems to be a highly reliable criterion for viral clearance, the HBsAg particles obtained may constitute a particularly efficient vaccine.
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PMID:Synthesis in animal cells of hepatitis B surface antigen particles carrying a receptor for polymerized human serum albumin. 609 51

Four major polypeptides with mol. wt. of 22000, 25000, 52000 and 68000 were isolated from solubilized preparations of hepatitis type B surface antigen (HBsAg). These four populations, referred to as P22, P25, P52 and P68, respectively, were used to immunize guinea-pigs. Guinea-pigs were also inoculated with HBsAg and with purified human serum albumin (HuSA). These antisera were utilized to establish that intact HBsAg particles are associated with HuSA antigenic reactivity. HuSA antigenic determinants were associated with purified preparations of P68. HuSA antigenic activity was not detected with purified preparations of P22, P25 and P52 or with respective specific antisera to each of the above. However, purified P68 contained the antigenic determinants of both host protein and hepatitis B virus-specified protein origin.
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PMID:Antigenic relationship of a hepatitis B surface antigen-derived polypeptide and human serum albumin. 615 94

Several investigators reported that sera from patients with liver disease react with polymerized human serum albumin. This reactivity may be mediated by antibodies to polymerized albumin or polymerized albumin receptor sites on HBsAg. We tested sera from 114 patients with a variety of liver diseases by techniques which differentiate polymerized albumin binding activity mediated by HBsAg-associated receptors from that due to immunoglobulins. Total polymerized albumin binding activity was detected by passive hemagglutination of polymerized albumin-coated red blood cells, in 62.3% of patients with liver disease. The specificity for polymerized albumin was proven by hemagglutination inhibition of 18 sera using polymeric, monomeric, and native albumin as inhibiting antigens. Indirect immunofluorescence of polymerized albumin coated red blood cells after incubation with serum revealed that antibodies, HBsAg or both mediated polymerized albumin binding. The predominant immunoglobulin class with polymerized albumin binding activity was IgG in sera from patients with chronic active hepatitis and alcoholic liver disease, and IgM in acute viral hepatitis, chronic persistent hepatitis, and primary biliary cirrhosis. HBsAg-mediated polymerized albumin binding activity was frequently associated with antibodies to polymerized albumin. The attachment of hepatitis B virus to hepatocytes may be facilitated by polymerized albumin via polymerized albumin receptors. Antibodies to polymerized albumin may interfere with this binding and may result in reduced infectivity.
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PMID:HBsAg-associated albumin receptors and antialbumin antibodies in sera of patients with liver disease. 616 Oct 62

On the basis of theoretical considerations, a peptide (H peptide) was synthesized by Hopp and Woods [Hopp, T. P. & Woods, K. R. (1981) Proc. Natl. Acad. Sci. USA 78, 3824---3828]. This peptide contains a sequence of six amino acids postulated to represent the major epitope, or antibody-combining site, of hepatitis B virus surface antigen (HBsAg). We have used passive hemagglutination inhibition with monospecific antibodies against the a, d, and y subdeterminants of this antigen and against human serum albumin to investigate the antigenic specificities on this peptide, and we have found it to contain the HBsAg/a and HBsAg/d but not HBsAg/y or human serum albumin subdeterminants. When the peptide was conjugated onto human erythrocytes and injected into mice, it induced the formation of anti-HBsAg with and without the use of Freund's adjuvant. If anti-HBsAg/a confers immunity to infection with hepatitis B virus, as is generally thought, these findings may permit the development of a synthetic vaccine lacking all unnecessary antigenic determinants.
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PMID:Hepatitis B virus vaccine: identification of HBsAg/a and HBsAg/d but not HBsAg/y subtype antigenic determinants on a synthetic immunogenic peptide. 617 97

17 monoclonal antibodies generated against purified hepatitis B surface antigen (HBsAg), subtype ayw, were characterized by solid-phase radioimmunoassays. Eleven of these antibodies had specificity against the group-specific alpha determinant of HBsAg, two demonstrated antibody activity against the w HBsAg subtype, one against human serum albumin, and three against human IgG. All monoclonal antibodies were of the IgG class.
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PMID:Characterization of anti-hepatitis B surface antigen monoclonal antibodies. 618 8

An antibody, which is distinct from the HBsAg- reacts with antigenic sites on Dane particles- HBcAg and HBeAg, was studied by radioimmunoprecipitation of radioactive intact hepatitis B virions in sera obtained early in the course of acute hepatitis type B. The antibody, previously termed anti-Dane particle (anti-DP) antibody, was reactive with Dane particles and HBsAg particles obtained from HBeAg-positive sera but not with HBsAg particles from anti-HBe containing sera. The expression on virus particles of the evoking antigen correlated with levels of binding sites for polymerized human serum albumin (pHSA) as detected by solid-phase radioimmunoassay. In acute hepatitis B sera, levels of anti-DP antibody activity showed inverse correlation with expression of pHSA receptors on circulating virus particles, although the two reactivities were not mutually exclusive. In inhibition experiments, pHSA blocked precipitation of Dane particles by anti-DP positive sera, while native human albumin and polymerized bovine albumin had no effect. The inhibition by pHSA of the anti-DP reaction appeared specific since identical concentrations of pHSA did not interfere with precipitation of virus particles by anti-HBs. Affinity chromatography studies with anti-DP insolubilized on Sepharose 4B columns showed selective binding to the gel of radioactive Dane particles; 125I-HBsAg was not reactive. The binding of Dane particles to anti-DP columns was completely inhibited when virus particles were applied to the gel in pHSA; pretreatment of the column with pHSA did not affect the reaction.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:An antibody which precipitates Dane particles in acute hepatitis type B: relation to receptor sites which bind polymerized human serum albumin on virus particles. 620 Apr 18

Recent evidence suggests that hepatitis B virions (HBV) and HBsAg particles contain receptors for polymerized human serum albumin (pHSA). We studied, by immunohistochemical techniques, the relationship between HBsAg and pHSA receptors in liver tissue from eight patients with chronic HBV infection and in a human hepatocellular carcinoma cell line (PLC/PRF/5) producing HBsAg. Both parallel sections and double fluorescent antibody staining of liver tissue demonstrated that only HBsAg-containing hepatocytes expressed pHSA receptors. The receptors could not be demonstrated in eight HBsAg negative livers. Sequential studies of PLC/PRF/5 cells revealed that pHSA and HBsAg emerged simultaneously in the cytoplasm, on the cell surface, and in the supernatant culture media. These findings indicate that pHSA receptors are closely associated with HBsAg during its synthesis and secretion by hepatocytes and suggest that the receptors are HBV-specific.
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PMID:Presence of receptors for polymerized albumin in HBsAg-containing hepatocytes and hepatoma cell line. 626 78

Seventeen out of 30 patients with chronic hepatitis type B with hepatitis B e antigen (HBeAg) in serum remained persistently positive for e antigen, while 13 seroconverted to antibody (anti-HBe) when followed over a period of one to five years. Initial levels of serum hepatitis B virus (HBV) markers, such as the hepatitis B surface antigen (HBsAg), HBeAg, and HBV-DNA polymerase (HBV-DNAP) were similar in the two groups of patients, while initial titres of the HBsAg-associated receptor for polymerized human serum albumin (pHSA), recently identified on HBV particles, were significantly higher in the patients who remained HBeAg positive (mean titre +/- SD = 2(-7.00) +/- 2(-3.2)) compared to the cases who eventually seroconverted to anti-HBe during the follow-up (2(-2.54) +/- 2(-2.14) P less than 0.001). A receptor titre above 1:64 by haemagglutination was highly predictive of persistence of HBeAg, suggesting that in patients with HBeAg-positive chronic hepatitis testing for the HBsAg-associated pHSA receptor may be useful in predicting the duration of HBe antigenaemia, with relevant clinical and prognostic implications.
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PMID:Virus receptors for polymerized human albumin: a prognostic marker in HBeAg-positive chronic hepatitis type B? 629 60

Recent studies of hepatitis B virus suggest that polymeric human serum albumin may facilitate the attachment of the virus via albumin receptors to hepatocytes during the infectious process. If this hypothesis is correct, hepatocytes should express binding sites for polymeric albumin. We employed the red blood cell adherence test using albumin-coated red blood cells as indicator cells on frozen sections of normal human livers to demonstrate these binding sites. Hepatocytes showed binding activity for both polymeric and monomeric albumin from different species. The receptor-ligand interaction was temperature and pH dependent, Ca++ independent and not altered by mercaptoethanol treatment. The binding activity was sensitive to neuraminidase and pronase, but resistant to trypsin, lipase and collagenase digestion. These findings suggest that human hepatocytes display species-non-specific albumin binding sites, which are glycoproteins.
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PMID:Albumin binding sites of human hepatocytes. 631 67


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