title: Antigenic structure of the hemagglutinin of H9N2 influenza viruses.
abstract: The hemagglutinins (HAs) of H9 influenza viruses isolated from birds and mammals of different species were antigenically and genetically analyzed. Antigenic variants were selected from A/swine/Hong Kong/10/98 (H9N2) and A/duck/Hokkaido/13/00 (H9N2) in the presence of monoclonal antibodies (MAbs). Based on the reactivity patterns of these mutants with a panel of MAbs, at least five non-overlapping antigenic sites were defined using eight MAbs which recognized seven distinct epitopes on the H9 HA molecule. Based on the reactivity patterns with the panel of monoclonal antibodies, 21 H9N2 virus strains isolated from birds and mammals were divided into 7 antigenically distinct groups. The present findings indicate that it is important to monitor the antigenic variation in H9 influenza viruses. The panel of MAbs in the present study, thus, should be useful for detailed antigenic analysis of the H9 HAs for epidemiological studies, the selection of vaccine strains, and diagnosis.
authors.affiliation: Laboratory of Microbiology, Department of Disease Control, Graduate School of Veterinary Medicine, Hokkaido University, North 18, West 9, Kita-ku, Sapporo, Hokkaido, 060-0818, Japan.
authors.forename: Masatoshi
authors.initials: M
authors.lastname: Okamatsu
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Sakoda
authors.forename: Noriko
authors.initials: N
authors.lastname: Kishida
authors.forename: Norikazu
authors.initials: N
authors.lastname: Isoda
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kida
mesh_terms: D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D000940:Antigenic Variation; D000956:Antigens, Viral / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D004372:Ducks / Q000276:immunology / Q000821:virology; D000939:Epitopes / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry / Q000235:genetics / Q000276:immunology*; D053127:Influenza A Virus, H9N2 Subtype / Q000145:classification / Q000235:genetics / Q000276:immunology*; D005585:Influenza in Birds / Q000276:immunology / Q000821:virology; D011487:Protein Conformation; D013552:Swine / Q000276:immunology / Q000821:virology
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D000956:Antigens, Viral; D000939:Epitopes; D019267:Hemagglutinin Glycoproteins, Influenza Virus