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)

Three major polypeptides of hepatitis B surface antigen (HBsAg), with mol. wt. 22,000 (p22), 27,000 (p27) and 68,000 (p68), were separated by preparative SDS-PAGE. These three peptides as well as intact HBsAg were found to have almost identical amino acid compositions and carbohydrate was detected in p27 and p68 by PAS staining. Papain treatment of p68 produced two distinct peptides p27 and p22. Moreover, when an artificial mixture of p27 and p22 in a ratio of 1:1 was treated with 0.2 M-periodate for 30 min at 37 degrees C, only p22 was detectable. These results suggest that p68 is composed of p27 and p22, and that p27 is a glycosylated product of p22. Thus, from the evidence obtained, it is possible that p22 (22,000 peptide) is the minimum size of the unique hepatitis B virus (HBV) gene product involved.
J Gen Virol 1980 May
PMID:Glycopeptide composition of hepatitis B surface antigen. 624 40

Cultures of two human hepatoma cell lines were examined for expression of hepatitis B virus surface antigen (HBsAg). The PLC/PRF/5 cells secreted HBsAg continuously into the culture medium, whereas Mahlavu cells did not secrete the antigen. However, cytoplasmic antigen was detected in a low percentage (less than 5%) of the Mahlavu cells. The expression of HBsAg also was assayed in cultures treated wtih dexamethasone (DXM), 5-iodo-2'-deoxyuridine (IdUrd), or both. The results demonstrated that: (i) DXM stimulated secretion of HBsAg by PLC/PRF/5 cells but not by Mahlavu cells; (ii) the percentage of Mahlavu cells expressing cytoplasmic HBsAg was not increased in any cultures if the medium was replaced at 24 t0 48 h intervals but was increased approx. fivefold within 4 days in cultures treated with DXM or IdUrd/DXM if the medium was not changed. However, no increase was noted in the intensity of the immunoperoxidase stain of PLC/PRF/5 cells that expressed cytoplasmic antigen in any DXM cultures; (iii) HBsAg expression was stimulated to a lesser extent in IdUrd/DXM cultures than in DXM cultures and was not enhanced in IdUrd cultures. Thus, DXM enhanced secretion of HBsAg by PLC/PRF/5 cells within 24 h and, after a delay, enhanced expression of cytoplasmic antigen by Mahlavu cells. However, antigen secretion by Mahlavu cells evidently was blocked.
J Gen Virol 1981 Mar
PMID:Induction of hepatitis B surface antigen in human hepatoma-derived cell lines. 626 37

Hepatitis B virus-related DNA was detected in the chromosomal DNA of three out of seven hepatocellular carcinomas and two out of five cirrhosis samples examined, by means of the blot-hybridization technique, described by Southern (1975). The integration patterns were not identical but some similarities raise the question of whether there are some preferred sites of viral integration.
J Gen Virol 1981 Nov
PMID:Detection of hepatitis B virus-specific DNA in the genomes of human hepatocellular carcinoma and liver cirrhosis tissues. 627 24

As demonstrated previously, a "beta particle" fraction isolated from the cytoplasm of PLC/PRF/5 cells contains hepatitis B virus (HBV)-specific DNA. Here, further evidence is provided that the specificity of the DNA for HBV is represented at least by sequences coding for the surface and core antigen (HBsAg and HBcAg). This was shown by two different hybridization techniques. One of them, the technique of Southern, distinguished these hybrid molecules formed from those containing HBV DNA integrated into chromosomes. The HBV-specific beta particle DNA forms two distinct bands separate from the high molecular weight cellular DNA.
J Gen Virol 1982 Jul
PMID:Evidence for non-chromosomal hepatitis B virus surface (HBsAg)- and core antigen (HBcAg)-specific DNA sequences in a hepatoma cell line. 628 45

Using the Southern blot technique, we have analysed the presence and state of hepatitis B virus (HBV) DNA in non-hepatic tissue from two human HBV carriers. HBV DNA sequences were detected in the pancreas, kidney and skin, demonstrating HBV infection of these organs. Moreover, the restriction DNA patterns were consistent with the integration of these viral sequences into high molecular weight DNA. These results demonstrate that HBV infection is not restricted to the liver.
J Gen Virol 1984 Mar
PMID:Detection of hepatitis B virus DNA in pancreas, kidney and skin of two human carriers of the virus. 669 25

Transfection of Buffalo rat liver cells with closed circular hepatitis B virus DNA resulted in the synthesis of both hepatitis B e and surface antigens. A 14000 mol. wt. peptide bearing hepatitis B e antigenic determinants was isolated from cell culture fluids. Native hepatitis B e antigen was present in multimeric forms in the cell culture fluids and was associated with protein phosphokinase activity. The multimeric forms of hepatitis B e antigen may serve both structural and enzymic functions for the hepatitis B virion with its small genome.
J Gen Virol 1984 Aug
PMID:Properties of hepatitis B e antigen synthesized by rat cells transfected with circular viral DNA. 674 6

In a search for additional antigens associated with virus-induced human liver disease a radioimmunoassay (RIA) was developed using IgG from sera of a multiply transfused person. Polystyrene beads coated with IgG F(ab)'2 fragments, dinitrophenylated F(ab)'2 fragments and 125I-labelled anti-2,4-dinitrophenyl antibodies (Neurath & Strick, 1979) were used in the RIA. An apparently new antigen or the corresponding antibodies were detected in 155 serum specimens from 35/37 (94%)individuals who developed non-A, non-B hepatitis. The antigen was also present in hepatitis B surface antigen-negative sera of blood donors with normal (13.2%) and elevated levels of alanine aminotransferase (34%). The antigen has an approximate mol. wt. of 45,000, a buoyant density of 1.23 g/ml and an isoelectric point of 7.
J Gen Virol 1980 Jun
PMID:An antigen detected frequently in human sera with elevated levels of alanine aminotransferase: a potential marker for non-A, non-B hepatitis. 677 39

Using immune electron microscopy (IEM), low-level cross-reactions could be demonstrated between the surface antigens of hepatitis B and woodchuck hepatitis. However, immune complex formation was greatly enhanced by pre-exposure of the antigens to 0.5% deoxycholate. Cross-reaction between the core antigens and e antigens of both viruses was also confirmed by IEM as well as radioimmunoassay. It appears that the woodchuck sera used in this study may well contain an anti-immunoglobulin akin to rheumatoid factor.
J Gen Virol 1983 Apr
PMID:Antigenic cross-reactions between woodchuck hepatitis virus and human hepatitis B virus shown by immune electron microscopy. 683 11

Liver sections from five patients with persistent hepatitis B virus (HBV) infection and active cirrhosis were shown to contain intracellular HBV DNA by in situ hybridization using cloned 3H-labelled HBV DNA probes. Two classes of infected cells, with different distributions throughout the liver, were distinguished: (i) cells containing a low copy number of double-stranded HBV nucleotide sequences, confined to the cell nucleus and thought to represent HBV DNA, and (ii) cells containing large amounts (estimated to be greater than 10 or 15 genome copies per cell) of HBV DNA, much of it in a single-stranded form and largely confined to the cell cytoplasm; these single-stranded regions represented widely separated regions of the HBV genome, in contrast to the structure of the DNA in mature virions. It is likely that these latter cells may be supporting viral DNA synthesis. Cells with large amounts of cytoplasmic HBV DNA invariably contained hepatitis B surface antigen (HBsAg) and in addition contained either no detectable hepatitis B core antigen (HBcAg), or cytoplasmic HBcAg or nuclear HBcAg in that order of frequency. Cytoplasmic HBcAg was highly predictive of the presence of large amounts of cytoplasmic HBV DNA in the same cell, while either nuclear HBcAg, or cytoplasmic HBsAg, were often seen both in cells with and without such levels of DNA. These patterns, relating HBV DNA and antigen content in naturally occurring asynchronous infection in a heterogeneous cell population, should provide a background to further studies of the virus replication cycle with a defined experimental system, when such a system becomes available.
J Gen Virol 1983 Jun
PMID:Patterns of single- and double-stranded hepatitis B virus DNA and viral antigen accumulation in infected liver cells. 685 69

Hepatitis B virus e antigen (HBeAg) derived from liver at autopsy or from the serum of asymptomatic carriers has been characterized. The liver-derived HBeAg consisted of two different molecules, one with a mol. wt. of 30 000 (monomer) and the other with a mol. wt. of 90 000 (trimer), in a ratio of 3:1. Both were free of IgG. The serum-derived HBeAgs were heterogeneous with mol. wt. of 30 000, 90 000, 240 000, 400 000 and 540 000. Among them, the so-called IgG-free HBeAgs consisted almost exclusively of the 30 000 and 90 000 molecular species, in a ratio of 1:9. The serum HBeAg of mol. wt. 90 000 was further differentiated into two molecular species, one trimer and the other associated with albumin. The large mol. wt. HBeAgs (240 000, 400 000 and 540 000) were associated with IgG in ratios of one molecule of HBeAg to one, two or three molecules of IgG respectively. The complete dissociation of the IgG molecule was not achieved by 5 M-urea treatment of such HBeAgs, suggesting that it was bound in an immune complex. A hypothetical model is proposed which describes the heterogeneity of the HBeAgs derived from both the liver and serum, and containing HBeAgs either in a free form or associated with serum IgG.
J Gen Virol 1981 Jul
PMID:Molecular heterogeneity of hepatitis B virus e antigen in liver and serum. 702 15


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