title: A monoclonal antibody against the X protein of hepatitis B virus: fine mapping of its epitope and application in a quantitative ELISA of the X protein in sera of hepatitis B patients.
abstract: A HBx-specific mouse monoclonal antibody was developed and its epitope mapped to a hydrophilic segment 94HKRTLGL100 using the multipin peptide synthesis technique. A sensitive ELISA with a threshold of 5 to 10 ng was developed to identify the HBx-positive hepatitis B cases and measure the levels of HBx in sera. The same patient sera were also analyzed for the presence of anti-HBx using the purified recombinant antigen. HBx was present in 23% of the cases (15/65) whereas only 14% of the cases (9/65) were positive for anti-HBx. The mean value of HBx in acute hepatitis sera was higher (522 ng/ml) than in cirrhosis cases (48 ng/ml). PCR amplification of the S gene showed that all 15 HBx-positive cases were also positive for the viral DNA.
authors.affiliation: Virology Group, International Centre for Genetic Engineering and Biotechnology, Aruna Asaf Ali Marg, New Delhi, India.
authors.forename: V
authors.initials: V
authors.lastname: Kumar
authors.forename: N
authors.initials: N
authors.lastname: Jayasuryan
authors.forename: H
authors.initials: H
authors.lastname: Reddi
authors.forename: D
authors.initials: D
authors.lastname: Sahal
authors.forename: S K
authors.initials: SK
authors.lastname: Panda
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000096:biosynthesis / Q000276:immunology*; D000914:Antibodies, Viral / Q000097:blood*; D000918:Antibody Specificity; D000956:Antigens, Viral / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay; D018604:Epitope Mapping; D006509:Hepatitis B / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D006515:Hepatitis B virus / Q000276:immunology*; D006801:Humans; D006825:Hybridomas / Q000276:immunology; D007124:Immunoenzyme Techniques; D008103:Liver Cirrhosis / Q000097:blood / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D015534:Trans-Activators / Q000097:blood* / Q000276:immunology*; D054334:Viral Regulatory and Accessory Proteins
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000956:Antigens, Viral; D015534:Trans-Activators; D054334:Viral Regulatory and Accessory Proteins; C057628:hepatitis B virus X protein