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)

Hepatitis B antigen (HBAg) has been demonstrated in conventional formalin-fixed paraffin-embedded liver tissue by peroxidase and fluorescent immunostaining as well as by orcein. Complete locational and morphologic identity is seen between material stained by specific immunologic methods and by orcein. The antigen is restricted to the cytoplasm and is generally observed in the hepatocyte; it is present in three morphologic forms. Certain morphologic forms can even be identified in hematoxylin and eosin-stained tissue. Results of immunostaining procedures indicate that the antigen demonstrated in this study consists entirely of surface coat of hepatitis B virus (HBsAg). This seems to be the only component revealed by orcein staining. The latter is considered to be a good marker of the surface antigen and to have certain advantages over immunostaining. It is suggested that suitability of conventional paraffin sections for the detection of HBAg has wide and important implications.
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PMID:Localization of hepatitis B surface antigen in conventional paraffin sections of the liver. Comparison of immunofluorescence, immunoperoxidase, and orcein staining methods with regard to their specificity and reliability as antigen marker. 5 76

A sensitive method for demonstrating the site of hepatitis B surface antigen (HBsAg) in fixed tissues embedded in either paraffin or araldite is described. The method employs the peroxidase-rabbit antiperoxidase linkage through goat antirabbit to rabbit anti-HBsAg. In staining hepatitis antigen in agar, comparison of fixation (using three common fixatives) with unfixed precipitation arcs revealed no recognizable differences in antigenicity induced by fixation. The method allows confirmation of positive reaction by appropriate blocking controls. The technic is compared with the orcein stain of Shikata and found to be somewhat more sensitive but slightly more time-consuming.
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PMID:An immunoperoxidase technic for the demonstration of the hepatitis B surface antigen in human livers. 5 16

In recent studies extrahepatic manifestations of viral hepatitis have been recognized as immune complex diseases. Hepatitis B surface antigen (HBsAg) has been successfully identified in immune complexes, but the pathogenic role of HBsAg-containing immune complexes (IC) remains questionable. The subject of the present study was the antigen-specific determination of IC in the course of hepatitis B virus infection using a new HBsAg-specific IC test (Pernice & Sedlacek, 1978). This test is based on the following principle: rabbit anti-HBs-coated polystyrole test tubes are incubated with the IC-containing test sample. The HBsAg-containing IC bind to the solid phase by their free antigenic determinants. There they can be quantified using a peroxidase-labelled anti-human IgG antibody. A good correlation was found between the level of HBsAg-containing immune complexes and the clinical state of six patients in a follow-up study. IC could be detected simultaneously with HBsAg and either decreased or disappeared before the occurrence of free anti-HBs. In the sera of an additional twenty-eight patient suffering from chronic active hepatitis, HBsAg-containing immune complexes were detected in 85% of cases. One patient suffering from polyarteritis nodosa was also positive. Occasionally, extremely high levels of IC were found in the course of these diseases.
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PMID:Antigen-specific detection of HBsAG-containing immune complexes in the course of hepatitis B virus infection. 9 65

Hepatitis B core antigen (HBcAg) and hepatitis B surface antigen (HBsAg) were localized in human liver tissues by the peroxidase-labeled antibody method at the light and electron microscopic levels. Several methods of fixation, staining, and inhibition of endogenous peroxidase activity were studied. The periodate-lysine-paraformaldehyde fixative effectively preserved the tissue structure and the antigenicity of both antigens, and the peroxidase-labeled Fab' fraction of IgG penetrated well into hepatocytes. HBcAg was present in nuclei, or cytoplasm of hepatic cells, or both. In nuclei, the antigen was found both in virus-like particles of approximately 20 nm. diameter and in nuclear ground substance. In the cytoplasm, the antigen was found on membrane-bound ribosomes and free polysomes, and also in the ground substance of the cytosol near ribosomes and around nuclear membranes, especially near nuclear pores. HBcAg-positive virus-like particles were also demonstrated sparsely or in clusters in the cytoplasm. HBsAg was not present in nuclei but was found in the perinuclear space and in cisternae of endoplasmic reticulum, and on nuclear, endoplasmic reticulum, and cell membranes of hepatic cells. HBsAg-positive 25- to 30-nm. wide tubular forms, round particles (probably cross-sections of tubular forms), and a few large particles of 40 to 50 nm. diameter were seen in cisternae. Such HBsAg-positive particles were also present in the intercellular space and in Disse's space. These findings suggest that HBcAg produced on the cytoplasmic ribosomes migrates through nuclear pores to the nucleus and is assembled into core particles there. These particles may then move through nuclear pores to the cytoplasm where they are invested with HBsAg-positive membrane in cisternae of endoplasmic reticulum or as they enter the endoplasmic reticulum. These virus particles are then released together with other HBsAg-positive forms into the intercellular space by reversed phagocytosis.
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PMID:Hepatitis B core and surface antigens in liver tissue. Light and electron microscopic localization by the peroxidase-labeled antibody method. 32 96

A solid-phase enzyme immunoassay for the qualitative detection of hepatitis B surface antigenemia is presented and the results compared to the counter-immunoelectrophoresis and radioimmunoassay methods for detection of the same antigen. The enzyme-antibody conjugate was prepared from horseradish peroxidase coupled with antibodies to three sub-types of hepatitis B virus. Polystyrene plastic tubes were used as the solid-phase support. The results of the enzyme immunoassay compare favorably with radioimmunoassay and exceed counterimmunoelectrophoresis in sensitivity.
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PMID:Enzyme immunoassay for hepatitis B and its comparison to other methods. 33 44

IgM antibody against core antigen of the hepatitis B virus (anti-HBc IgM) was selectively determined by a new enzyme immunoassay (EIA). Microtiter plates were coated with anti-human micro chain immunoglobulin. On addition of serum IgM is bound by a factor of about 4,000 more than IgG. After removing the sample, HBcAg is added to the IgM-coated surface. Binding takes place if the IgM contained anti-HBc and was demonstrated by the aid of a conjugate made from anti-HBc IgG and horse radish peroxidase. Quantitation may be achieved without testing a dilution series. The assay was not disturbed by a large excess of anti-HBc IgG in the sample and rheumatoid factor did not produce false-positive results, provided the sample was diluted in an excess of aggregated IgG. The diagnostic relevance of the assay was demonstrated in selected cases of acute hepatitis B. Rapid diagnosis of acute hepatitis B infection is therefore now possible in those cases whihc are HBsAg-negative but anti-HBc-positive.
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PMID:Selective detection of IgM-antibody against core antigen of the hepatitis B virus by a modified enzyme immune assay. 39 75

The present report describes a sensitive and reliable method for potentiometric determination of hepatitis B surface antigen in biological fluids, as an application of enzyme-linked immunoassay technique by a "sandwich" procedure. Specific antibodies are immobilized on a gelatine membrane which covers the sensor of an iodide-sensitive electrode. After immersion of the modified electrode in a dilute solution of antigen, the enzymatic activity is evaluated in a solution of peroxidase-labelled antibodies, in the presence of substrate and iodides. The electrode potential is a function of antigen concentration in the solution. This new procedure should find its application in the determination of substances present in very low concentration in biological fluids.
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PMID:[Potentiometric determination of hepatitis B surface antigen in biological fluids (author's transl)]. 69 28

Peritoneal liver biopsy specimens from eight patients with hepatitis B associated cirrhosis, complicated by hepatocellular carcinoma, were studied for identification and localisation of myofibroblasts. The avidin-biotin peroxidase complex technique was used on paraffin wax sections, using monoclonal antibodies for actin and desmin, and ultrastructural examination was performed. Myofibroblasts were found in seven of the eight cirrhotic specimens and in all eight tumour specimens. They were identified in the fibrotic areas by the immunohistochemical technique, but ultrastructural examination disclosed their presence in the perisinusoidal space and between tumour cells.
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PMID:Myofibroblasts in hepatitis B related cirrhosis and hepatocellular carcinoma. 131 87

Immunohistochemical evaluation of Cu, Zn- and Mn-superoxide dismutase (SOD) activity in various viral liver diseases was performed by the peroxidase-conjugated antibody indirect method. Anti-human Cu, Zn-SOD (rabbit) and anti-human Mn-SOD (guinea-pig) derived and purified from SOD of human erythrocytes and placentas were used to determine SOD distribution in liver tissues. SOD in the liver tissues was detected in 68 inpatients of our unit. They consisted of 23 cases with chronic hepatitis caused by hepatitis B virus (13) and hepatitis C virus (10), 24 with liver cirrhosis caused by hepatitis B virus (5) and hepatitis C virus (19) (15: compensatory, 9: decompensatory) and 21 with hepatocellular carcinoma caused by hepatitis B virus (2) and hepatitis C virus (18) complicated of liver cirrhosis. In viral liver diseases, SODs in the liver tissues were distributed to hepatocytes mainly in the pattern of cytoplasmic diffusion. The incidence of immunohistochemical Cu, Zn-SOD and Mn-SOD were 47.8% and 56.5% in chronic hepatitis, 93.3% and 86.7% in compensated liver cirrhosis, 11.1% and 22.2% in decompensated liver cirrhosis, respectively. The aggression of viral liver disease was accompanied with the decrease of SOD concentration in the liver tissues. Hepatocellular carcinoma cells were negative for Mn-SOD in all cases, and weakly positive for Cu, Zn-SOD in 2 out of 21 cases. Comparatively strongly positive SOD findings were obtained from normal regions neighboring carcinomas. A close relationship between the depletion of SOD in liver tissues and carcinogenesis in viral liver diseases was observed.
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PMID:Relationship between superoxide dismutase (SOD) and viral liver diseases. 132 May 79

The expression of transforming growth factor alpha (TGF-alpha) was examined in a human hepatoblastoma cell line, Hep G2, which does not contain hepatitis B virus (HBV) DNA, and in the cell line 2.2.15, which was formed by the transfection of Hep G2 cells with the complete HBV DNA, to study the possibility that HBV and TGF-alpha could function as co-factors in hepatocarcinogenesis. Northern blot hybridization of RNA extracted from these cell lines, with densitometric analysis, revealed expression of the TGF-alpha gene in the transfected cells at a level three times higher than in the nontransfected cells. Staining of the cells using a monoclonal antibody to TGF-alpha and the avidin-biotin-peroxidase immunohistochemical method revealed a much higher intensity of TGF-alpha staining in the transfected cell line. These findings show that the presence of HBV DNA appears to cause a significant up-regulation of the TGF-alpha gene. This effect on the TGF-alpha gene may be a mechanism by which HBV contributes to the etiology of hepatocellular carcinoma in some patients.
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PMID:Increased expression of transforming growth factor alpha after transfection of a human hepatoblastoma cell line with the hepatitis B virus. 132 1


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