title: Serum Neutralization Assay for the Determination of Antibody Levels Against Non-Polio Enterovirus Strains in Central and Western Greece.
abstract: Mutations and recombination events have been identified in enteroviruses. Point mutations accumulate with a frequency of 6.3 × 10(-4) per base pair per replication cycle affecting the fitness, the circulation, and the infectivity of enteroviral strains. In the present report, the serological status of the Central and Western Greek population (Larissa and Ioannina, respectively) in the 1-10-year, 11-20-year, 21-30-year, and 31-40-year age groups against six non-polio enterovirus strains, their respective echovirus prototypes, and Sabin 1, 2, and 3 vaccine strains was evaluated, through serum-neutralization assay. In the Western Greek population, antibody levels were detected only for clinical isolates of E30 serotype in all age groups, and for environmental isolate LR61G3 (E6 serotype) only in the 31-40 age group, whereas an immunity level was observed in the Central Greek population, against all strains, except for EIS6B (E3 serotype). Amino acid substitutions were encountered across the structural region of the capsid, between the prototypes and the respective isolates. These substitutions may alter the antigenicity of each strain and may explain the variations observed in the neutralization titers of the different strains. As a consequence, these substitutions severely affect antibody binding and increase the ability of the virus to escape the immune response. It is tempting to assume that changes in the antigenic properties observed in circulating echoviruses represent a selection of viral variants that are less prone to be neutralized by human antibodies. These facts argue for the need of immunological studies to the population to avoid epidemics due to the circulation of highly evolved derivatives.
authors.affiliation: 1 Microbiology-Virology Laboratory, Department of Biochemistry & Biotechnology, School of Health Sciences, University of Thessaly , Larissa, Greece .
authors.forename: Antonis
authors.initials: A
authors.lastname: Fikatas
authors.affiliation: 1 Microbiology-Virology Laboratory, Department of Biochemistry & Biotechnology, School of Health Sciences, University of Thessaly , Larissa, Greece .
authors.forename: Tilemachos G
authors.initials: TG
authors.lastname: Dimitriou
authors.affiliation: 1 Microbiology-Virology Laboratory, Department of Biochemistry & Biotechnology, School of Health Sciences, University of Thessaly , Larissa, Greece .
authors.forename: Zaharoula
authors.initials: Z
authors.lastname: Kyriakopoulou
authors.affiliation: 1 Microbiology-Virology Laboratory, Department of Biochemistry & Biotechnology, School of Health Sciences, University of Thessaly , Larissa, Greece .
authors.forename: Ourania
authors.initials: O
authors.lastname: Tsachouridou
authors.affiliation: 2 Department of Microbiology, Medical School, University of Ioannina , Ioannina, Greece .
authors.forename: Constantina
authors.initials: C
authors.lastname: Gartzonika
authors.affiliation: 2 Department of Microbiology, Medical School, University of Ioannina , Ioannina, Greece .
authors.forename: Stamatina
authors.initials: S
authors.lastname: Levidiotou-Stefanou
authors.affiliation: 1 Microbiology-Virology Laboratory, Department of Biochemistry & Biotechnology, School of Health Sciences, University of Thessaly , Larissa, Greece .
authors.forename: Grigoris D
authors.initials: GD
authors.lastname: Amoutzias
authors.affiliation: 1 Microbiology-Virology Laboratory, Department of Biochemistry & Biotechnology, School of Health Sciences, University of Thessaly , Larissa, Greece .
authors.forename: Panayotis
authors.initials: P
authors.lastname: Markoulatos
mesh_terms: D000293:Adolescent; D000328:Adult; D019943:Amino Acid Substitution; D057134:Antibodies, Neutralizing / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood*; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D004770:Enterovirus / Q000235:genetics / Q000276:immunology*; D004769:Enterovirus Infections / Q000453:epidemiology* / Q000276:immunology; D006115:Greece / Q000453:epidemiology; D006801:Humans; D007223:Infant; D009500:Neutralization Tests / Q000379:methods*; D016036:Seroepidemiologic Studies; D055815:Young Adult
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D036022:Capsid Proteins