title: Sequence and phylogenetic analyses of human rotavirus strains: comparison of VP7 and VP8(∗) antigenic epitopes between Tunisian and vaccine strains before national rotavirus vaccine introduction.
abstract: Group A rotaviruses (RVA) are the leading cause of severe gastroenteritis in infants and young children worldwide. Due to their epidemiological complexity, it is important to compare the genetic characteristics of vaccine strains with the RVA strains circulating before the introduction of the vaccine in the Tunisian immunization program. In the present study, the nucleotide sequences of VP7 and VP8∗ (n=31), the main targets for neutralizing antibodies, were determined. Comparison of antigenic epitopes of 11 G1P[8], 12 G2P[4], 4 G3P[8], 2 G4P[8], 1 G6P[9] and 1 G12P[8] RVA strains circulating in Tunisia from 2006 to 2011 with the RVA strains present in licensed vaccines showed that multiple amino acid differences existed in or near putative neutralizing domains of VP7 and VP8∗. The Tunisian G3 RVA strains were found to possess a potential extra N-linked glycosylation site. The Tunisian G4 RVA were closely related to the G4 vaccine strain in RotaTeq, belonging to the same lineage, but the alignment of their VP7 amino acids revealed an insertion of an asparagine residue at position 76 which is close to a glycosylation site (aa 69-71). Despite several differences detected between Tunisian and vaccine strains, which may affect binding of neutralizing antibodies, both vaccines are known to protect against the vast majority of the circulating genotypes, providing an indication of the high vaccine efficiency that can be expected in a future rotavirus immunization program.
authors.affiliation: UR06SP20, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia.
authors.forename: Ben Hadj Fredj
authors.initials: BH
authors.lastname: Mouna
authors.forename: Meriam Ben
authors.initials: MB
authors.lastname: Hamida-Rebaï
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Heylen
authors.forename: Mark
authors.initials: M
authors.lastname: Zeller
authors.forename: Amal
authors.initials: A
authors.lastname: Moussa
authors.forename: Saoussen
authors.initials: S
authors.lastname: Kacem
authors.forename: Marc
authors.initials: M
authors.lastname: Van Ranst
authors.forename: Jelle
authors.initials: J
authors.lastname: Matthijnssens
authors.forename: Abdelhalim
authors.initials: A
authors.lastname: Trabelsi
mesh_terms: D000595:Amino Acid Sequence; D000956:Antigens, Viral / Q000235:genetics* / Q000276:immunology; D036022:Capsid Proteins / Q000235:genetics* / Q000276:immunology; D000939:Epitopes / Q000235:genetics; D019143:Evolution, Molecular; D005838:Genotype; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000276:immunology; D012401:Rotavirus / Q000235:genetics* / Q000276:immunology* / Q000302:isolation & purification; D012400:Rotavirus Infections / Q000453:epidemiology / Q000821:virology*; D022243:Rotavirus Vaccines / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D016415:Sequence Alignment; D014416:Tunisia / Q000453:epidemiology; D017361:Viral Nonstructural Proteins / Q000235:genetics* / Q000276:immunology
chemical_list: D000956:Antigens, Viral; D036022:Capsid Proteins; D000939:Epitopes; D016601:RNA-Binding Proteins; D022243:Rotavirus Vaccines; C050779:VP7 protein, Rotavirus; D017361:Viral Nonstructural Proteins; C079234:NS35 protein, rotavirus
keywords: Genotype; Mutations; Phylogeny; Rotavirus; Vaccine