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)

Serologic tests for hepatitis B prevalence and immunogenetic characterizations were carried out on a sample of 800 persons from several isolated tribes of the lower Amazon basin and the southern Andes. The prevalence of hepatitis B antigen carriers and of antibody to the surface antigen varied from one tribe to another, but were high in all the forest tribes. The serologic evidence indicated high infection rates early in life, but also an increasing proportion showing evidence of infection with increasing age. The frequency of past infections was not differentially associated with the antigen status of the mother or father. A higher proportion of infected males than females had antigenemia. Contrary to published reports, no association of antigenemia was found with any HLA-A, B or C antigen or immunoglobulin allotype, individually or interactively. Antibody prevalence, however, did differ in persons with different HLA haplotypes.
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PMID:Hepatitis B epidemiology and its relation to immunogenetic traits in South American Indians. 348 98

beta 2-Microglobulin display was examined in 131 liver biopsies from patients with acute and chronic type B hepatitis, using an indirect immunoperoxidase method. Enhanced expression of beta 2-microglobulin on hepatocyte membranes was observed in patients with acute hepatitis, chronic active hepatitis with moderate to severe activity and cirrhosis, when compared with normal liver. In acute hepatitis, beta 2-microglobulin-positive hepatocytes were mainly observed in perivenular areas in association with bridging necrosis. In chronic hepatitis, beta 2-microglobulin-positive hepatocytes were observed mainly in periportal zones and in some areas of lobular activity. Diffuse-enhanced display of beta 2-microglobulin on hepatocytes was observed in 5 of 6 patients treated with lymphoblastoid interferon as part of a trial of antiviral therapy. The mechanism by which beta 2-microglobulin display is enhanced on hepatocytes in patients not treated with interferon is uncertain. However, display of beta 2-microglobulin on hepatocytes probably reflects display of HLA-A, B and C antigens and may influence the course of hepatitis B virus infection by increasing susceptibility of the affected cells to T cell-mediated immune attack.
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PMID:Expression of beta 2-microglobulin on hepatocytes in acute and chronic type B hepatitis. 351 Sep 50

The frequency of 26 HLA-A and B antigens and of antibodies to the hepatitis B core antigen (anti-HBc) and surface antigen (anti-HBs) has been studied in 150 alcoholic patients divided into 3 groups: I) n = 50, isolated hepatic steatosis; II) n = 50, acute alcoholic hepatitis +/- cirrhosis; III) n = 50, cirrhosis without acute alcoholic hepatitis. For the control group 184 blood donors were selected. In all these subjects, as in all the alcoholic patients, the Alsatian origin of four grand parents was proved. An increased frequency of HLA-B15 was observed in group III (34 p. 100) compared to the control group (9.8 p. 100) (corrected p less than 0.001). There was no significant difference between the four groups for all the other HLA antigens. In group III, the prevalence of anti-HBc and/or anti-HBs was higher in patients with HLA-B15 (64.7 p. 100) than in patients without this antigen (15.1 p. 100) (p less than 0.001). In groups I and II, there was no significant difference. These results suggest that there is a genetic predisposition to cirrhosis without acute alcoholic hepatitis, dependent on HLA-B15 antigen. This predisposition could involve the hepatitis B virus.
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PMID:[Prevalence of HLA-A and -B antigens, anti-HBc and -HBs antibodies in alcoholic hepatopathies]. 387 4

Cytotoxic T lymphocyte (CTL) activity against HBs antigen (HBsAg)-coated autologous mononuclear cells as target cells was examined in hepatitis B virus infection. Target cells were prepared by coincubation of mononuclear cells with purified HBsAg in 0.5 mM CrCl3. The distribution and uniformity amounts of HBsAg on target cells was shown by immune fluorescence and by analyzing the fluorescence intensity with a fluorescent activated cell sorter. CTL activity was detected in 7 of 9 patients with acute hepatitis type B, in 4 of 11 chronic active hepatitis type B, in none of 8 healthy HBsAg carriers, and in none of 22 healthy volunteers. The antigen specificity of the cytotoxicity was confirmed by a blocking experiment with purified HBsAg and by cold target inhibition with HBsAg or bovine serum albumin (irrelevant antigen) coupled cold target cells. CTL lysed HBsAg coupled allogeneic target cells that shared HLA-A or B locus antigens. This finding suggests that HLA restriction may be involved in the killing mechanism. This HBsAg specific CTL clone may participate in the immunopathogenesis of hepatitis B virus infection.
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PMID:Hepatitis B surface antigen specific cytotoxic T lymphocyte activity in hepatitis B virus infection. 387 61

an analysis of the expression of the histocompatibility antigens in the livers of patients with chronic hepatitis B virus infection and normal subjects has demonstrated an increased expression of HLA-A, B, C antigens on the hepatocytes of patients with a low level of viral replication (HBe antibody positive) as compared with patients who exhibit a high level of viral replication (HBe antigen positive) and controls. This increase in the expression of histocompatibility antigens on the hepatocytes was associated with a decrease in the membrane expression of viral antigens by the same cells. These differences in the density of HLA and viral antigen display may influence the efficiency of T-cell cytolysis of hepatitis B virus-infected hepatocytes.
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PMID:Hepatitis B virus and HLA antigen display in the liver during chronic hepatitis B virus infection. 711 68

This study was undertaken to assess the frequency of development and the stages of evolution of chronic liver disease in patients with renal failure who are chronic carriers of hepatitis B surface antigen. Cirrhosis or chronic active hepatitis developed in five of 21 patients and could not be predicted by the initial histological appearance or by HLA-A and B typing but was associated with the e antigen in four of the five patients. However, the antigen was not a consistent indicator of a poor prognosis, as the four other e antigen positive patients did not develop chronic liver disease during the period of the study. Transmission of hepatitis B to spouses occurred in four cases, was fatal in one instance, and was associated with e antigen in three of the four. Determination of e antigen status in renal unit patients who are carriers of hepatitis B surface antigen may be of value to the patient and his home environment.
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PMID:Liver disease and the e antigen in HBsAg carriers with chronic renal failure. 738 Mar 32

Direct MHC binding assays with radiolabeled peptides and HLA class I-expressing mammalian cells such as EBV-transformed B cell lines and PHA-activated blasts have been developed. Significant binding of the radiolabeled probe could be obtained if the target cells were preincubated overnight at 26 degrees C in the presence of beta 2-microglobulin. Under these conditions, up to a few percent of the HLA molecules expressed by either cell type could be bound by the labeled peptides. With these assays, the degree of cross-reactivity of the A*0201-restricted hepatitis B virus core 18-27 peptide with other A2 subtypes was examined. It was determined that this peptide epitope also binds the A*0202, A*0205, and A*0206 but not A*0207 subtypes. Inhibition experiments with panels of synthetic peptide analogues underlined the similar ligand specificities of the HLA-A*0201, A*0202, and A*0205 alleles. Analysis of the polymorphic residues that help form the B and F pockets of various HLA alleles allowed prediction of binding of the hepatitis B virus core 18-27 epitope to two other HLA alleles (HLA-A*6802 and A*6901). Thus, it appears that a family of at least six different HLA-A molecules may share overlapping ligand specificities (aliphatic residues in position 2 and at the C termini). These results suggest that broadly cross-reactive peptide epitopes can be identified and greatly enhance the prospective feasibility of peptide-based vaccination approaches.
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PMID:Binding of a peptide antigen to multiple HLA alleles allows definition of an A2-like supertype. 752 83

The HLA multigene family consists of HLA class I (HLA-A, B and C) and class II (HLA-DR, DQ and DP) genes, and plays a central role in the regulation of immune response. To investigate how each HLA gene and each HLA allele contribute to the human immune response, we immunized 339 healthy Japanese medical students with recombinant hepatitis B surface antigen (rHBsAg) and determined the HLA types of all vaccinated subjects at the DNA level. The anti-HBs antibody titers showed a log-normal distribution, implying that the immune response to HBsAg in humans is a multifactorial and continuous trait. A stepwise multiple regression analysis demonstrated the alleles at the HLA-class I (HLA-A and B) and class II (HLA-DRB1, DQA1, DQB1, DPA1 and DPB1) loci significantly contributed to antibody production to HBsAg. The predicting equation of anti-HBs antibody levels for individuals with any HLA phenotype was proposed based on a multiple regression analysis. The multiple correlation coefficient of antibody production to HBsAg with the HLA-DRB1 locus was highest (0.34) among all of the HLA loci, whereas those with whole HLA class I or class II loci were 0.36 or 0.44 respectively. The incorporated correlation coefficient of the presence of all HLA gene families with antibody production became 0.50, suggesting that HLA class I and class II loci within the HLA multigene family are dynamically involved in regulation of the immune response to HBsAg.
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PMID:Contribution of HLA class I and class II alleles to the regulation of antibody production to hepatitis B surface antigen in humans. 867 39

Between June 1990 and August 1997, 304 mainly pediatric patients underwent a total of 311 orthotopic living related liver transplantations (LRLTs) under tacrolimus immunosuppression at Kyoto University Hospital. Congenital biliary atresia was the most common underlying disease. The donor was a parent, and the left lateral segments were used as grafts in most cases. The average number of loci of HLA-A, -B, and -DR mismatches between the donor and the recipient were 2.1. Forty-three transplants were ABO-incompatible. Liver histology at the time of abnormal liver function after transplantation was analyzed. Preservation injury was rare and mild. Acute cellular rejection (ACR) occurred in 36% of transplants during the first 6 months. Average rejection activity index (the Banff schema) was 4.2 and severe rejection was rarely seen. The number of mismatching HLA loci and immunosuppression regimens affected the incidence of ACR. Chronic rejection (CR) occurred in 2% of transplants. Concerning humoral rejection, no hyperacute rejection was seen. However, hepatic artery thrombosis (delayed hyperacute rejection) was seen in an ABO-incompatible transplant. Acute hepatitis, including those related to cytomegalovirus and Epstein-Barr virus, occurred in 17% of transplants. Chronic hepatitis, including hepatitis B and C, developed in 3%. Acute or chronic cholangitis occurred in 16%, and a significantly higher incidence of cholangitis was found in ABO-incompatible transplants. Posttransplantation lymphoproliferative disease developed in 2%. In LRLT, milder preservation injury and less frequent ACR and CR were suggested, probably because of the short cold-ischemia time and the advantages of HLA histocompatibility, respectively.
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PMID:Living related liver transplantation: histopathologic analysis of graft dysfunction in 304 patients. 1066 27

Genetic factors are implicated in the response of normal subjects to hepatitis B vaccine. In order to investigate the immunogenetic factors associated with nonresponsiveness to hepatitis B vaccine, 93 health care workers were vaccinated with hepatitis B vaccine. Initial nonresponders (antibody not detected or antibody detected but < 10 mlU/ml) were revaccinated. Only 12 (12.9%) of the 93 health care workers, who had anti-HBs levels of 10 mlU/ml or less after revaccination were defined as absolute nonresponders. HLA typing were performed in these 12 nonresponders, Anti-HBs levels were determined by ELISA method in mlU/ml units. HLA-A,B,C,DR, and DQ typing was performed using the microcytotoxicity test. The HLA-A10 (pc less than 0.01) and CW4 (pc less than 0.006) were decreased whereas DR7 (pc less than 0.09) was increased in nonresponders. Although our initial results suggest the importance of genetic modulation of responsiveness to hepatitis B vaccine, a formal demonstration of the mode of inheritance of unresponsiveness to hepatitis B vaccine and the explanation of the role of genes in this matter will require further studies of families.
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PMID:HLA tissue types in nonresponders to hepatitis B vaccine. 1083 13


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