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)

Binding specificity of a monoclonal antibody (mAb) (kappa, gamma 2b) H8 which can react with the pre-S2 peptide of hepatitis B virus (HBV) was determined by Western blot analyses. From the hybridoma cell line secreting mAb H8, poly(A)+ RNA was prepared and used as a template for cDNA synthesis and cloning. Full-length cDNAs coding for the heavy and kappa light chains of the mAb were cloned from the cDNA library and characterized by nucleotide (nt) sequence analyses and N-terminal amino acid sequencing. The sequence analyses revealed that both heavy and light chain-specific cDNAs are functional, and the variable regions of the heavy and light chains are members of mouse heavy chain subgroup III(c) and light chain group I, respectively. Comparison of the nt sequences with mouse immunoglobulin genes listed in the GenBank data base show that the cDNAs have not been previously reported. The cDNAs will be used for the construction of a therapeutic antibody for HBV infection.
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PMID:Cloning and characterization of cDNAs coding for heavy and light chains of a monoclonal antibody specific for pre-S2 antigen of hepatitis B virus. 144 32

The preS(21-47) sequence of the hepatitis B virus (HBV) envelope protein is involved in binding of the virus to cell receptors. A protein similarity search revealed a partial homology between this sequence and a segment of the human immunoglobulin A (IgA) heavy chain constant region, suggesting that the cell attachment site for HBV might be located on secretory component representing a receptor for polymeric IgA. Data presented herein do not support this hypothesis but provide evidence for immunological cross-reactivity between IgA and the preS(21-47) region of the HBV env protein.
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PMID:Antigenic mimicry of an immunoglobulin A epitope by a hepatitis B virus cell attachment site. 169 50

Human hepatocyte growth factor (hHGF) was purified from the plasma of six patients with fulminant hepatic failure due to hepatitis B in two and non-A, non-B hepatitis in four. The purified hHGF from each patient contained two major protein bands having molecular weights of 79,000 and 86,000 and several minor bands having molecular weights between 76,000 and 92,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis performed under nonreduced conditions. After reduction with 2-mercaptoethanol, three major bands having molecular weights of 58,000, 34,500, and 31,500 were evident. In addition, a band having a molecular weight of 21,000 was detected. hHGF activity was destroyed by its reduction. The hHGF purified from patients demonstrated a dose response in terms of an increase in DNA synthesis using cultured hepatocytes. The hHGF concentration in the plasma of the patients with grade III-IV hepatic coma was calculated to be in the range of 1.8-3.0 nM. Finally the heavy chain of hHGF was not recognized by an anti-human albumin antibody, indicating that hHGF is not biliprotein, an albumin-bilirubin complex, that has been reported to be a putative liver growth factor.
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PMID:Human hepatocyte growth factor in blood of patients with fulminant hepatic failure. Basic aspects. 182 62

Factor VIII deficient plasma was made from pooled, HIV antibody and hepatitis B antigen screened, normal human plasma by cryoprecipitation and immuno-depletion, using three different monoclonal antibodies bound to Sepharose columns, in series. These monoclonal antibodies are specific respectively for von Willebrand factor, factor VIII heavy chain and factor VIII light chain. The immunodepleted plasma contained less than 0.002 u/ml factor VIII coagulation activity (VIII:C) less than 0.0001 u/ml von Willebrand factor antigen and 1-2 g/l fibrinogen, while the levels of other clotting factors were unchanged. This immunodepleted plasma was compared with commercial factor VIII deficient plasma obtained from a severe haemophilia A patient as substrate in the one-stage factor VIII assay. Plasmas obtained from 20 normal subjects and 28 patients with von Willebrand's disease or haemophilia A were assayed for VIII:C using the two substrates. The results were very highly correlated (r = 0.96). The columns have high capacity and can be regenerated at least 10 times. Large-scale production of a substrate for factor VIII assays free of virus contamination is now feasible.
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PMID:Production of factor VIII deficient plasma by immunodepletion using three monoclonal antibodies. 311 89

Two class I major histocompatibility complex (MHC) proteins with molecular masses of 43- and 39-kDa were identified in the cell surface membranes of normal woodchucks using a newly developed antiwoodchuck class I monoclonal antibody (mAb) B1b.B9 and immunoblotting. B1b.B9 was generated by immunizing mice with viable woodchuck peripheral blood mononuclear cells and was selected for anti-class I MHC reactivity using a cellular enzyme-linked immunoassay, indirect immunofluorescence on tissue sections and flow cytofluorimetry. The distribution pattern of class I MHC antigen on woodchuck lymphoid cells was found to be similar to that reported in other species. Also, the antigen expression on normal woodchuck hepatocytes was comparable to that observed on normal human liver parenchymal cells; thus, the antigen was not detected on hepatocytes by staining of liver tissue sections, but was found by indirect immunofluorescence staining of isolated liver cells. Western blot analysis of the plasma membranes from normal woodchuck hepatocytes revealed the presence of a single species of class I MHC heavy chain protein with a molecular mass of 43-kDa, whereas splenocyte plasma membranes showed intense expression of a 43-kDa species, as well as the presence of a 39-kDa protein. The 39- and 43-kDa proteins were extracted with Triton X-114 to the hydrophobic protein phase, suggesting that they both contain a hydrophobic transmembrane domain. The data obtained indicate that the B1b.B9 identifies a nonpolymorphic epitope of woodchuck class I MHC heavy chains, providing an important reagent for the study of the pathogenesis of hepatitis B virus infection in a woodchuck model.
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PMID:Identification of woodchuck class I MHC antigens using monoclonal antibodies. 765 41

We recently showed that a synthetic peptide corresponding to the third complementary determining region of the heavy chain (CDRH3) of a monoclonal antibody (mAb) directed to the V3 domain of HIV-1 gp120 neutralizes HIV-1 in vitro. From the CDRH3 sequence we have now produced bifunctional antigen/antibody specificity exchanger (A/ASE) peptides containing both the HIV-1 mAb derived CDRH3 sequence and antigenic region sequences from the hepatitis B virus core/e antigen (HBc/eAg) and the poliovirus VP1. These A/ASE peptides were able to re-direct HBc/eAg and enteroviral VP1 specific mAbs, as well as polyclonal human HIV-1 negative sera to recognize the V3 domain of HIV-1. Furthermore, two out of three A/ASE peptides were able to neutralize HIV-1 in vitro. These bifunctional A/ASE peptides have a potential to be used as tools in research, diagnostics and maybe even therapeutics.
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PMID:The antigen/antibody specificity exchanger: a new peptide based tool for re-directing antibodies of other specificities to recognize the V3 domain of HIV-1 gp120. 780 74

We have produced and characterized a murine-human chimeric antibody with specificity for the pre-S2 surface antigen of hepatitis B virus (HBV) in baculovirus-infected insect cells. Recombinant baculovirus carrying the cDNA coding for the heavy or light chain of the chimeric antibody was constructed and co-infected into insect cells. The chimeric antibody (BV-S2) expressed in the cells was purified by an affinity chromatography on Protein A-Sepharose 4B column and characterized by N-terminal amino acid sequencing, affinity determination for pre-S2 peptide, endoglycosidase digestion and Clq binding assay, which were then compared with those of the chimeric antibody H69K that has the same amino acid sequence as BV-S2, but produced from transfected murine myeloma cells. The N-linked glycosylation of the BV-S2 antibody was also analyzed by culturing the baculovirus-infected cells in the presence of tunicamycin. The results showed that the BV-S2 was secreted following correct removal of the leader peptides, contained N-linked carbohydrate at the heavy chain, and had the same binding affinity and Clq binding ability as H69K, suggesting that the BV-S2 chimeric antibody is functional and thus may be useful in the prevention of HBV infection.
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PMID:Characterization of a murine-human chimeric antibody with specificity for the pre-S2 surface antigen of hepatitis B virus expressed in baculovirus-infected insect cells. 857 64

We cloned and analyzed the cDNA sequences encoding the variable regions of a human monoclonal antibody (23HN) (gamma1, kappa) that binds to the common a antigenic determinant on hepatitis B surface antigen and its fine epitope is different from those of previously known mAbs with the same specificity. The heavy and light chain variable regions are the members of human heavy chain subgroup III and kappa light chain subgroup III, respectively, and are most homologous to human germline VH segment DP-50 and Vkappa segment DPK-22, respectively.
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PMID:Cloning and sequence analysis of cDNAs encoding the heavy and light chain variable regions of a human monoclonal antibody with specificity for hepatitis B surface antigen. 956 74

In the present study, the genetic mechanisms responsible for generation of antibodies recognizing the dominant epitope within a synthetic peptide PS1CT3 were examined. PS1CT3 is a peptide model antigen containing residues 28-42 of the large protein of the surface antigen of hepatitis B virus as B epitope (designated PS1), and the known T-helper-cell epitope derived from the circumsporozoite protein of the malaria parasite Plasmodium falciparum (designated CT3). To characterize the repertoire generated, the immunoglobulin heavy chain variable regions from IgM and IgG monoclonal antibodies against PS1CT3 were sequenced. Although all IgG monoclonal antibodies were directed against the immunodominant epitope, the genetic elements used were diverse. Comparison of the sequence of germ line precursor IgM to a mature IgG revealed that during maturation of the primary IgM response only the heavy chain fragment of the antibody molecule underwent somatic mutation.
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PMID:B-cell responses to a peptide epitope: mutations in heavy chain alone lead to maturation of antibody responses. 1044 8

Woodchuck hepatitis virus (WHV), similar to human hepatitis B virus, causes acute liver inflammation that can progress to chronic hepatitis and hepatocellular carcinoma. WHV also invades cells of the host lymphatic system, where it persists for life. We report here that acute and chronic hepadnavirus hepatitis is characterized by a profound difference in the expression of class I major histocompatibility complex (MHC) molecules on the surface of infected hepatocytes and, notably, lymphoid cells. While acute WHV infection is accompanied by the enhanced hepatocyte surface presentation of class I MHC antigen and upregulated transcription of the relevant hepatic genes, inhibition of class I antigen display on liver cells is a uniform hallmark of chronic WHV infection. This inhibition in chronic hepatitis occurs despite augmented (as in acute infection) expression of hepatic genes for class I MHC heavy chain, beta(2)-microglobulin, and transporters associated with antigen processing (TAP1 and TAP2). Further, the class I antigen inhibition is not related to the histological severity of hepatocellular injury, the extent of lymphocytic infiltrations, the level of intrahepatic gamma interferon induction, or the hepatic WHV load. Importantly, the antigen expression is also inhibited on organ lymphoid cells of chronically infected hosts. The results obtained in this study demonstrate that the defective presentation of class I MHC molecules on cells supporting persistent WHV replication is due to viral posttranscriptional interference. This event may diminish the susceptibility of infected hepatocytes to virus-specific T-cell-mediated elimination, hinder virus clearance, and deregulate the class I MHC-dependent functions of the host immune system. This multifarious effect could be critical for perpetuation of liver damage and evasion of the antiviral immunological surveillance in chronic infection and therefore could be supportive of hepadnavirus persistence.
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PMID:Posttranscriptional inhibition of class I major histocompatibility complex presentation on hepatocytes and lymphoid cells in chronic woodchuck hepatitis virus infection. 1077 84


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