New monoclonal antibody, useful for diagnosis and treatment of hepatitis B infection, is specific for highly conserved epitope

摘要

A monoclonal antibody (I) that binds to wild-type hepatitis B surface antigen (HBsAg) and to at least one, preferably more than 2, mutant forms of the antigen, is new. It binds to a peptide sequence of at least 6 consecutive amino acids (aa) in the 199-208 region of the antigen, particularly to this region. Independent claims are also included for the following: (1) fragments or derivatives (II) of (I); (2) preparing (M1) a hybridoma that expresses (I); (3) hybridomas (III) produced by (M1); (4) preparing (M2) of (I) by culturing (III); (5) detecting (M3) HBsAg using (I) or its fragments; (6) diagnostic composition (IV) containing (I) and optionally a reagent for detected hepatitis B core antigen; (7) antisera (V) containing (I) or its fragments or derivatives; (8) anti-idiotypic antibodies (VI) directed against (I) or its fragments or derivatives; (9) HBsAg epitope (VII), comprising aa 199-208, of sequence (S1); (10) immunogenic peptide (VIII) that comprises or consists of (VII), or contains at least 3 aa homologous, or identical, to aa in (VII); (11) preparing (M4) of (I) or its fragments using (VIII); (12) nucleic acid probe or primer (IX) that hybridizes under stringent conditions to a sequence that encodes (VII), its complement or derived RNA; (13) diagnostic composition (X) containing (IX); and (14) hybridization or amplification assay (XI) for in vitro detection of the DNA or RNA of hepatitis B virus, using (IX). Tyr-Tyr-Trp-Gly-Pro-Ser-Lys-Tyr-Ser-Ile (S1)