title: Comparison of human saliva and synthetic histo-blood group antigens usage as ligands in norovirus-like particle binding and blocking assays.
abstract: Blocking of norovirus-like particle binding to their cellular ligands, histo-blood group antigens with immune sera, is considered a surrogate norovirus neutralization assay. We compared human secretor positive saliva and synthetic biotinylated carbohydrates as a source of histo-blood group antigens in binding and blocking assays. Six norovirus capsid-derived virus-like particles belonging to genogroup I (GI-1-2001 and GI-3-2002) and genogroup II (GII-4-1999, GII-4-2010 New Orleans, GII-4-2012 Sydney and GII-12-1998) noroviruses were produced by a recombinant baculovirus expression system and binding profile to saliva type A, B and O and to synthetic antigens (A trimer, B trimer, H type 1, H type 3, Lewis(a) and Lewis(b)) was identified. Good correlation between virus-like particle binding to saliva type A and synthetic A trimer (r = 0.66, p < 0.05) and saliva type B and synthetic B trimer (r = 0.75, p < 0.05) was observed. Binding of each norovirus virus-like particle to the selected histo-blood group antigens was blocked by convalescent sera from NoV-infected subjects or type-specific mouse antisera. Our results support the use of either saliva or synthetic antigens in blocking assay to measure the ability of norovirus antisera to block virus-like particle binding to the carbohydrate ligands.
authors.affiliation: Vaccine Research Center, University of Tampere Medical School, Biokatu 10, FI-33520 Tampere, Finland.
authors.forename: Hanni
authors.initials: H
authors.lastname: Uusi-Kerttula
authors.affiliation: Vaccine Research Center, University of Tampere Medical School, Biokatu 10, FI-33520 Tampere, Finland.
authors.forename: Kirsi
authors.initials: K
authors.lastname: Tamminen
authors.affiliation: Vaccine Research Center, University of Tampere Medical School, Biokatu 10, FI-33520 Tampere, Finland.
authors.forename: Maria
authors.initials: M
authors.lastname: Malm
authors.affiliation: Vaccine Research Center, University of Tampere Medical School, Biokatu 10, FI-33520 Tampere, Finland; Department of Pediatrics, Tampere University Hospital, Teiskontie 35, FI-33521 Tampere, Finland.
authors.forename: Timo
authors.initials: T
authors.lastname: Vesikari
authors.affiliation: Vaccine Research Center, University of Tampere Medical School, Biokatu 10, FI-33520 Tampere, Finland. Electronic address: vesna.blazevic@uta.fi.
authors.forename: Vesna
authors.initials: V
authors.lastname: Blazevic
mesh_terms: D000818:Animals; D001789:Blood Group Antigens / Q000737:chemistry*; D002241:Carbohydrates / Q000737:chemistry; D005260:Female; D005838:Genotype; D006801:Humans; D007106:Immune Sera / Q000737:chemistry; D008024:Ligands; D051379:Mice; D008807:Mice, Inbred BALB C; D012463:Saliva / Q000737:chemistry*; D014771:Virion / Q000737:chemistry; D053585:Virus Attachment
chemical_list: D001789:Blood Group Antigens; D002241:Carbohydrates; D007106:Immune Sera; D008024:Ligands
keywords: Ligand binding; Neutralization; Norovirus; Virus-like particle