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

The surface antigens of human hepatitis B (HBsAg), ground squirrel hepatitis (GSHsAg), and woodchuck hepatitis (WHsAg) viruses were compared serologically, and their major polypeptides were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and tryptic peptide mapping. Results showed that both GSHsAg and WHsAg are antigenically cross-reactive, that their major pairs of polypeptides have identical mobilities on sodium dodecyl sulfate gels, and that the major polypeptides of GSHsAg and WHsAg migrate faster in sodium dodecyl sulfate-polyacrylamide gel electrophoresis than do the corresponding bands of HBsAg. The peptide maps of the major (P-22) surface antigen polypeptides of GSHsAg and WHsAg showed that they shared over half of their spots. Peptide mapping of HBsAg subtypes indicated a close relationship between the major polypeptides (P-24) of adw and adr and a more distal relationship to ayw. Only about 25% of the spots shared by the combined HBsAg subtypes were also found in the peptide maps of GSHsAg and WHsAg, indicating at least some structural homology among the major polypeptides of the human and animal virus surface antigen particles. This is also reflected in the serological cross-reactivity among HBsAg, GSHsAg, and WHsAg. Further, the detection of ground squirrel and woodchuck antigens by Ausria II radioimmunoassay, combined with peptide mapping data indicating the common origin of these viruses, suggests that the common a determinant is shared by each and is restricted to approximately 25% of the sequences in their major polypeptides.
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PMID:Antigenic and structural relationships of the surface antigens of hepatitis B virus, ground squirrel hepatitis virus, and woodchuck hepatitis virus. 616 76

Hepatitis B surface antigens (HBsAg) of both the adw and ayw subtypes were reductively methylated with formaldehyde in the presence of sodium cyanoborohydride. The effect on antigenicity was determined by radioimmunoassay with monoclonal antibodies specific for seven different antigenic determinants. The reaction was shown to eliminate specifically the "d" antigenic activity of HBsAg/adw and to have no effect on HBsAg/ayw. Moreover, the reaction had only a slight affect on HBsAg/adw at one of the "a" antigenic determinants. The sites of modification were determined and the extent of modification of each site was compared to the loss of "d" antigenic activity. These studies demonstrated that the loss of "d" activity was due to the modification of lysine 122 in HBsAg/adw, and that although the amino terminus and lysine residues 141 and 160 of both HBsAg/adw and HBsAg/ayw are reactive, their modification does not alter any measurable antigenic activity.
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PMID:Antigenic structure of hepatitis B surface antigen: identification of the "d" subtype determinant by chemical modification and use of monoclonal antibodies. 619 78

The antigenic specificity of measles virus IgM antibodies in sera from patients with chronic active hepatitis not caused by hepatitis B virus has been examined. An immunosorbent column containing antihuman IgM covalently bound to Sepharose was used to pick up IgM from the sera. Radiolabelled measles virus antigens were then allowed to react with the IgM antibodies. The immune complexes were eluted and analysed by sodium dodecyl sulfate [SDS]-polyacrylamide gel electrophoresis. Four sera from patients with hepatitis B surface antigen [HBsAg]-negative chronic active hepatitis with high measles virus haemagglutination inhibition [HI] and complement fixation [CF] antibody titres and positive enzyme-linked immunosorbent assay [ELISA] for measles-virus-specific IgM were examined. The results were compared with those obtained using sera from patients with an acute measles virus infection and from healthy controls. In both patient groups, IgM antibodies with specificity against the matrix protein represented the major portion of the measles virus IgM. IgM antibodies against the measles virus nucleoprotein and probably against host-cell-derived actin were also present. The patient sera contained only traces of IgM antibodies with specificity against the measles virus haemagglutinin or fusion protein. No specific IgM antibodies were found in sera from healthy controls.
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PMID:IgM antibodies in sera from patients with chronic active hepatitis reacting with the measles virus matrix protein and nucleoprotein. 620 19

The efficient in vitro inhibition of hepatitis B virus DNA polymerase by trisodium phosphonoformate (PFA, INN: foscarnet sodium) and its low toxicity suggested that PFA could be used as a therapeutic agent for hepatitis B infection. PFA was also found to inhibit woodchuck hepatitis virus (WHV) DNA polymerase in vitro. As a model to test PFA's eventual effect, chronically WHV infected woodchucks were treated with PFA. The animals were treated twice daily in a dosage which gave a minimum serum level of PFA corresponding to an in vitro inhibiting effect on WHV DNA polymerase of about 40%. The concentration in liver tissue was found to be 15% below serum level. The amount of WHV particles in serum was followed by DNA polymerase assay. No effect on WHV production could be seen during 2 weeks' treatment. No change of the in vitro sensitivity to PFA of the WHV DNA polymerase was seen. These results indicate that the WHV associated DNA polymerase has no role in the production of viral particles.
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PMID:No in vivo effect of trisodium phosphonoformate on woodchuck hepatitis virus production. 622 May 63

We introduced the gene encoding the hepatitis B virus surface antigen (HBsAg) into simian virus 40 (SV40)-based plasmids capable of autonomously replicating in both Escherichia coli and permissive monkey cells. After introduction into monkey cells by transfection, these plasmids directed the synthesis of high levels of HBsAg, as determined by immunofluorescence, radioimmunoassays, and identification by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the polypeptides comprising the antigen. Expression was dependent upon the presence of an SV40 promoter, with both the early and late promoters able to effectively initiate transcription. Using expression of HBsAg to assay promoter function, we demonstrated that an intact copy of the SV40 72-base pair repeat, which constitutes an essential element of the SV40 early promoter during the lytic SV40 cycle and which can enhance the transcriptional activity of heterologous promoters, was not required for HBsAg expression, suggesting that the hepatitis genome contains an enhancer element capable of complementing that provided by the 72-base pair repeat element of SV40. The antigen appears to be glycosylated after synthesis in transfected cells and is apparently secreted, as evidenced by the localization of [35S]cysteine-labeled antigen to the medium of transfected cultures. Using constructions in which the first ATG sequence appearing in HBsAg mRNA was that corresponding to the gene encoding the mature form of the antigen, we demonstrated that these post-translational events could occur without the involvement of a putative precursor peptide suggested by the DNA sequence of the viral genome. In view of the inability of hepatitis B virus to propagate in vitro, this strategy offers a convenient approach for further characterizing the biosynthesis of this antigen and may provide a means to identify additional polypeptides encoded by this virus.
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PMID:Plasmid-directed synthesis of hepatitis B surface antigen in monkey cells. 629 7

Four aspects for the use of PLC/PRF/5 cell line as an alternative source of HBsAg for hepatitis B vaccine production were assayed in this study: improvement in HBsAg production with chemical inducers, tests for the presence of hepatitis B virions, antigenic topology of HBsAg polypeptides and immunogenicity of HBsAg in guinea pigs. 10(-6) M dexamethasone and/or 10(-4) M sodium butyrate treatments enhanced HBsAg production by a factor of approximately two when compared with untreated cells. Particles of 35 nm diameter produced by PLC/PRF/5 cells were observed at a CsCl density of 1.22-1.24, associated with typical HBsAg 22 nm spheres. These particles did not contain HBV DNA as proved by negative results of hybridization using cloned HBV/DNA as a probe. Western blot analysis revealed that only polypeptides P 22000 (P1) and P 26000 (P2) were specifically recognized by a human anti-HBs serum, irrespective of the origin of HBsAg, i.e. human serum or PLC/PRF/5 hepatoma cell line. HBsAg purified from PLC/PRF/5 cell line was immunogenic in guinea pigs. However, the humoral response was delayed and lower in terms of anti-HBs titers when compared to the response obtained after immunization with a licensed hepatitis B vaccine (HEVAC B, Institut Pasteur Production).
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PMID:Further studies on production and characterization of HBsAg derived from a human hepatoma cell line (PLC/PRF/5). 631 96

The existence of a lactate dehydrogenase-immunoglobulin A kappa complex was demonstrated as a marked increase of lactate dehydrogenase activity at the lactate dehydrogenase-3 band in the agar-agarose gel-electrophoresis pattern of sera from seven patients from an unselected group of 21 800 patients. The complex was isolated, in an almost pure form, by gel filtration and affinity chromatography, from the serum of a patient with circulating hepatitis B surface antigen. The complex had a relative molecular mass (Mr) of approximately 445 000 as determined by gel filtration. Electrophoresis in sodium dodecyl sulfate in the absence of reducing agents showed the presence of two subunit bands with Mr 170 000 and 34 000. We therefore propose that the native complex consists of one monomeric immunoglobulin A kappa linked to two tetrameric lactate dehydrogenase molecules. The enzymic activity of the complex is probably from lactate dehydrogenase isoenzyme-5.
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PMID:Partial characterization, properties, and clinical significance of a lactate dehydrogenase-immunoglobulin A kappa complex in serum. 640 3

The potential of alkaline 2% glutaraldehyde solutions, with and without surface active agents, to alter the antigenicity of hepatitis B virus (HBV) was analyzed and compared to the antigenic alternation capacities of 0.525% sodium hypochlorite and 2.02% formaldehyde solutions. After treatment of a hepatitis B surface antigen-positive plasma at room temperature for 10 min, there was a 51-67% reduction in surface antigen level and a 90-94% decrease in hepatitis B core antigenicity. Glutaraldehyde is proposed as an alternative to the more noxious hypochlorite and formaldehyde solutions for disinfection of HBV-contaminated articles.
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PMID:Effect of alkaline glutaraldehyde on hepatitis B virus antigens. 641 9

The unavailability of serological tests for detection of several not yet characterized infectious agents transmitted by blood transfusion or by blood products prompted the development of alternative tests based on utilization of labeled nucleic acid probes specific for genomes of each of these agents. The prerequisite for the preparation of such probes is the demonstration in human plasma of nucleic acid sequences distinct from those present in host DNA or in genes of already characterized viruses occurring in plasma of infected individuals. To accomplish this, ultrasensitive tests for nucleic acids not dependent on their base sequence are needed. We describe here a radioimmunoassay (RIA) for picogram quantities of DNA. Plasma (serum) specimens are treated with proteinase K in the presence of sodium dodecyl sulfate and extracted with phenol. Nucleic acids are precipitated with ethanol in the presence of dextran (mol. wt. approximately equal to 5 X 10(5)) as carrier. Subsequently, DNA from the redissolved samples is adsorbed onto polylysine-coated wells of microtiter plates and detected by a double-antibody RIA using anti-DNA autoantibodies from NZB/NZW mice and 125I-labeled antibodies to mouse immunoglobulins. DNA which did not hybridize with human DNA was detected by this method in sera containing hepatitis B virus used as a model system.
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PMID:Strategies for detection of transfusion-transmitted viruses eluding identification by conventional serologic tests. I. Radioimmunoassay for picogram quantities of DNA. 641 51

The relationships of various polypeptides associated with hepatitis B surface antigen (HBsAg), ground squirrel hepatitis surface antigen (GSHsAg), woodchuck hepatitis surface antigen (WHsAg), and duck hepatitis B surface antigen (DHBsAg) were studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and tryptic peptide mapping. Analysis of independent antigen isolates by SDS-PAGE resulted in bands consistently observed at 24,000, 28,000, 32,000, 43,000, and 50,000 Da with HBsAg; at 22,000, 25,000, 35,000, 37,000, 39,000, and 42,000 Da with GSHsAg and WHsAg; and at 18,500, 30,000, and 38,500, Da with DHBsAg. Comparison of the major polypeptide pair from the mammalian viruses by tryptic peptide mapping suggests more than a single point of glycosylation or other post-translational modification(s) in some paired comparisons and/or heterogeneity in glycosylation in others. Comparison of the major component of each mammalian virus (HBsAg p24, GSHsAg p22, or WHsAg p22), or the major polypeptide of DHBsAg (p18.5), with their respective larger polypeptides by peptide mapping indicated that one or more of the larger components in each virus shares extensive homology with the appropriate major component. Further, these larger components possess additional spots, interpreted as additional primary sequences, which were not found in the map of the appropriate major component. Collectively, the results suggest that a number of surface antigen-associated polypeptides may be partially encoded for by the pre-S gene region known to exist in hepatitis B virus (HBV) and woodchuck hepatitis virus (WHV), and likely to exist in ground squirrel hepatitis virus (GSHV) and duck hepatitis B virus (DHBV) DNA.
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PMID:The nature of polypeptides larger in size than the major surface antigen components of hepatitis b and like viruses in ground squirrels, woodchucks, and ducks. 663 42


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