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)

A new capture enzyme immunoassay for the determination of immunoglobulin M (IgM) antibodies against hepatitis B core antigen (HBcAg) is described. Core antigen produced in Escherichia coli was labeled with biotin and subsequently detected by an avidin-biotin-peroxidase complex. The biotin-labeled core antigen was effective at concentrations as low as 20 ng/ml. Of 561 serum samples from different groups of patients that were tested, 465 samples were negative for other hepatitis B virus markers and also for anti-HBcAg IgM. Sera from the early stages of hepatitis B infection had high levels of anti-HBcAg IgM, and a clear correlation with the acuteness of the disease was observed in 45 follow-up sera from 23 patients with acute or recent hepatitis B. Sera from 21 patients with past hepatitis B were all negative for anti-HBcAg IgM. Twenty serum samples from chronic carriers of hepatitis B surface antigen showed slightly elevated antibody levels for anti-HBcAg IgM. Ten sera which were positive for anti-HBcAg IgG antibodies and had high levels of rheumatoid factor were negative for anti-HBcAg IgM.
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PMID:Determination of immunoglobulin M antibodies for hepatitis B core antigen with a capture enzyme immunoassay and biotin-labeled core antigen produced in Escherichia coli. 390 76

A sandwich ELISA for hepatitis B virus surface antigen (HBsAg) was developed using monoclonal anti-HBs for the solid phase and horse-radish peroxidase labelled sheep anti-HBs. The sensitivity was approx. 0.3 U/ml HBsAg, in the standard test procedure, comprising two incubation steps of 1 h at 37 degrees C, or in a shortened procedure comprising two incubation steps of 30 min at 50 degrees C. A slightly reduced sensitivity (approx. 0.5 U/ml) was obtained when the two incubations were combined in a one-step incubation for 1 h at 37 degrees C. All three procedures were completed by an incubation for 30 min at room temperature with peroxide and tetra-methylbenzidine. The number of false positives obtained when donor sera were screened was below 0.5%. False positive reactions occurred more frequently, but still to a limited extent, when previously selected sera containing rheumatoid factor or other possibly interfering factors were tested with the standard procedure. Most sera containing factors that interfere with a commercial ELISA for HBsAg using sheep anti-HBs coated plates, were negative. Rheumatoid factor positive sera seldom gave false positive results. The lower detection limit became approx. 0.1 U/ml when the cut-off was reduced, while the number of false positives in a donor population only increased to 1.5%. The results obtained with reagents from four different batches indicate a stability of up to 4 wk at 37 degrees C and for at least 26 wk at 4 degrees C.
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PMID:Improved ELISA for the detection of HBsAg. 399 41

An enzyme-linked immunosorbent assay (ELISA) was developed for the detection and quantitation of antibodies (anti-HBs) to the surface antigen of the hepatitis B virus (HBsAg). The ELISA uses HBsAg as the solid phase, and, after conjugation to horseradish peroxidase, also as the conjugate. Conditions for this assay were optimized and a rapid (1.5 hours) ELISA has evolved which works very satisfactorily for the large-scale screening of donated blood. We have used this ELISA to examine donated blood in Natal and concluded that we cannot initiate a programme of anti-HBs supplementation of parenteral blood products without hyperimmunization and plasmapheresis of selected, voluntary donors.
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PMID:Safer blood--supplementation of blood products with anti-HBs. 403 90

The localization of hepatitis B antigen (HB Ag) and the nature of the virus-like particles in hepatocytes of patients with HB antigenemia are controversial. In many reports, numerous virus-like particles have been demonstrated in hepatocytic nuclei; the few reported in the cytoplasm are insufficient in number to explain the intense cytoplasmic fluorescence after staining with fluoresceinated antibody to HB Ag (HB Ab). We found numerous tubular and circular structures, measuring 20 to 30 nm in diameter, in the cisternae of the excess smooth endoplasmic reticulum (ER) of varying numbers of hepatocytes in 13 of 16 HB Ag carriers and in 4 of 9 patients with HB Ag-positive chronic hepatitis corresponding to cytoplasmic HB Ag-specific fluorescence. Direct immunoelectronmicroscopy using peroxidase-labeled HB Ab revealed that the intracisternal bodies and the surrounding membranes contain HB antigenic determinants. These bodies are an ultrastructural correlate of cytoplasmic HB Ag. It is suggested that they are virally coded coat material rather than the mature hepatitis B virus or its core.
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PMID:Electron microscopy and immunoelectronmicroscopy of cytoplasmic hepatitis B antigen in hepatocytes. 413 80

A case is reported in which non-A, non-B posttransfusion hepatitis was followed serially by chronic persistent hepatitis, chronic active hepatitis, and liver cirrhosis that finally developed into hepatocellular carcinoma. The patient died after a 19-year clinical course. During the last 8 years, repeated attempts to identify serum hepatitis B surface antigen, antibody to hepatitis B surface antigen, and antibody to hepatitis B core antigen were consistently negative. Liver biopsy was performed five times during the clinical course, and at autopsy, liver tissue was obtained from four different nontumor regions. These specimens were investigated by a peroxidase immunoenzyme method which failed to detect hepatitis B surface antigen and hepatitis B core antigen. Non-A, non-B posttransfusion hepatitis may become chronic and sometimes may advance to hepatocellular carcinoma.
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PMID:Hepatocellular carcinoma after non-A, non-B posttransfusion hepatitis. 609 43

In the process of establishing the specificity of direct immunoperoxidase staining of liver tissue for hepatitis B surface antigen (HBsAg), an affinity of free horseradish peroxidase (HRP) for HBsAg in hepatocytes (ground-glass cells) was found. Of 95 patients, the horseradish peroxidase reaction was only positive in the livers of the 35 who were chronically HBsAg seropositive and not in the livers from 60 control patients with alcoholic cirrhosis who were HBsAg seronegative. Comparison studies using the orcein technic and immunoperoxidase methods confirmed the observation that both free horseradish peroxidase (not conjugated to an antibody) and HRP conjugated to an antibody unrelated to HBsAg had an affinity to the cytoplasm of hepatocytes containing HBsAg. The precise nature of this affinity is not known, but it is probably due to a reaction between an activated carbohydrate moiety of horseradish peroxidase and the free amino group of HBsAG.
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PMID:Nonimmunologic binding of horseradish peroxidase to hepatitis B surface antigen. A possible source of error in immunohistochemistry. 615 65

Different forms of hepatocellular proliferation are seen in fetal livers, massive hepatic necrosis, and nodular transformation (nodular regenerative hyperplasia) of the liver. In an attempt to characterize the proliferating cells in these conditions, we studied the expression of several antigens by immunohistochemical methods. Alpha-fetoprotein (AFP), alpha 1-antitrypsin (AAT), a hepatocellular export protein, carcinoembryonic antigen (CEA), a marker of bile duct epithelial cells, and hepatitis B virus antigens (HBsAg, HBcAg), were localized by the peroxidase-antiperoxidase method in 11 fetal livers, 10 cases of nodular transformation, and 7 cases of massive hepatic necrosis. AFP was the most prevalent antigen in fetal hepatocytes. Many hyperplastic hepatocytes in nodular transformation contained AAT, but not oncofetal antigens, supporting the differentiated hepatocellular nature of these cells. A similar staining pattern was seen in two-cell-thick plates of hepatocytes in massive hepatic necrosis. In contrast, the ductlike structures at the periphery of necrotic lobules contained both AAT and CEA, suggesting that these cells exhibit features of hepatocytes and bile duct epithelial cells. Therefore, the appropriate term for these regenerating cells appears to be "ductular" or "biliary hepatocytes".
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PMID:Phenotypic characterization of hepatic proliferation. Antigenic expression by proliferating epithelial cells in fetal liver, massive hepatic necrosis, and nodular transformation of the liver. 618 4

An affinity of horseradish peroxidase for hepatitis B surface antigen (HBsAg), irrespective of antigen-antibody conjugation, was disclosed incidentally, and a new staining method of HBsAg was established. The new technique is simple, inexpensive and available for formalin-fixed, paraffin embedded sections, and does not require fresh liver tissue. Compared with three other methods, involving Shikata's orcein staining, the conventional immunoperoxidase method, and the peroxidase-anti-peroxidase method, it showed high specificity and sensitivity, which were not lower than the other three methods. Conjugation of horseradish peroxidase with HBsAg was confirmed by affinity chromatography. Attention should be paid to the fact that there is a possibility of obtaining false positive results by immunoperoxidase methods, staining antigens other than HBsAg in HBsAg positive liver tissue because of antigen-antibody independent affinity of peroxidase for HBsAg.
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PMID:A new staining method for hepatitis B surface antigen by horseradish peroxidase. 618 4

Primary hepatocellular carcinoma metastasizing to abdominal lymph nodes and to the left lung was observed in a 16-year-old male patient. No clinically apparent chronic liver disease preceded the carcinoma and no signs of cirrhosis were detectable in the nonneoplastic liver. Hepatitis B surface antigen, hepatitis B e antigen and antibody to hepatitis B core antigen were found to be positive in the serum. By immunohistochemistry (peroxidase-antiperoxidase technique) hepatitis B surface antigen could be demonstrated in the nontumorous liver parenchyma, but not in the primary hepatocellular carcinoma itself. Serum alpha-fetoprotein was only moderately elevated (75 ng/ml), but immunohistochemically primary hepatocellular carcinoma revealed a considerable number of alpha-fetoprotein-containing cells, whereas nontumorous parenchyma did not. Carcinoembryonic antigen could be demonstrated immunohistochemically in some tumor cells of a lymph node metastasis, but not in the primary tumor or in the nontumorous liver parenchyma. We propose that primary hepatocellular carcinoma developed in this case in a symptomless hepatitis B virus carrier without preceding cirrhosis, an we exclude a simultaneous acute hepatitis B.
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PMID:Primary hepatocellular carcinoma with hepatitis B virus infection in a 16-year-old noncirrhotic patient. 618 92

1. Sections previously stained with hematoxylin-eosin and periodic acid-Schiff were destained and subjected to the peroxidase-antiperoxidase (PAP) technique for the identification of the following antigens: hepatitis B surface antigen, hepatitis B core antigen, alpha-1-antitrypsin, alpha-fetoprotein, immunoglobulin G and immunoglobulin M. 2. The results obtained after destaining of previously stained sections were similar to those obtained with material that had not been stained, indicating that the sensitivity and specificity of the immunological reaction had not been affected by the previous treatments. 3. The results reported here extend the number of antigens that can be detected by the PAP technique after destaining of sections stained by traditional histochemical methods and consequently increase the opportunity for retrospective studies.
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PMID:The efficacy of the immunoperoxidase technique for the detection of several antigens after destaining of stored stained sections. 618 37


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