title: Exploring the antigenic relatedness of influenza virus haemagglutinins with strain-specific polyclonal antibodies.
abstract: Alternative methods to the standard haemagglutination inhibition (HI) and neutralization tests to probe the antigenic properties of the influenza virus haemagglutinin (HA) were developed in this study. Vaccinia virus recombinants expressing reference HAs were used to immunize rabbits from which polyclonal antibodies were obtained. These antibodies were subtype specific but showed limited intra-subtype strain specificity in ELISA. The discriminatory capacity of these antibodies was, however, markedly increased after adsorption to cells infected with heterologous influenza viruses, revealing antigenic differences that were otherwise undistinguishable by standard HI and neutralization tests. Furthermore, the unadsorbed antibodies could be used to select escape mutants of the reference strain, which after sequencing unveiled amino acid changes responsible of the noted antigenic differences. These procedures therefore provide alternative methods for the antigenic characterization of influenza HA and might be useful in studies of HA antigenic evolution.
authors.affiliation: CIBER de Enfermedades Respiratorias, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.|Biología Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
authors.forename: Blanca
authors.initials: B
authors.lastname: García-Barreno
authors.affiliation: CIBER de Enfermedades Respiratorias, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.|Biología Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
authors.forename: Teresa
authors.initials: T
authors.lastname: Delgado
authors.affiliation: CIBER de Enfermedades Respiratorias, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.|Biología Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
authors.forename: Sonia
authors.initials: S
authors.lastname: Benito
authors.affiliation: Virus Respiratorios & Gripe, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Casas
authors.affiliation: Virus Respiratorios & Gripe, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Pozo
authors.affiliation: CIBER de Enfermedades Respiratorias, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.|Biología Viral, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Majadahonda, 28220 Madrid, Spain.
authors.forename: José A
authors.initials: JA
authors.lastname: Melero
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000276:immunology*; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005822:Genetic Vectors; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000276:immunology*; D006801:Humans; D007114:Immunization / Q000379:methods; D009975:Orthomyxoviridae / Q000276:immunology*; D011817:Rabbits; D014616:Vaccinia virus / Q000235:genetics
chemical_list: D000914:Antibodies, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus