title: Characterization of cross-reactive norovirus-specific monoclonal antibodies.
abstract: Noroviruses (NoVs) commonly cause acute gastroenteritis outbreaks. Broadly reactive diagnostic assays are essential for rapid detection of NoV infections. We previously generated a panel of broadly reactive monoclonal antibodies (MAbs). We characterized MAb reactivities by use of virus-like particles (VLPs) from 16 different NoV genotypes (6 from genogroup I [GI], 9 from GII, and 1 from GIV) coating a microtiter plate (direct enzyme-linked immunosorbent assay [ELISA]) and by Western blotting. MAbs were genotype specific or recognized multiple genotypes within a genogroup and between genogroups. We next applied surface plasmon resonance (SPR) analysis to measure MAb dissociation constants (Kd) as a surrogate for binding affinity; a Kd level of <10 nM was regarded as indicating strong binding. Some MAbs did not interact with the VLPs by SPR analysis. To further assess this lack of MAb-VLP interaction, the MAbs were evaluated for the ability to identify NoV VLPs in a capture ELISA. Those MAbs for which a Kd could not be measured by SPR analysis also failed to capture the NoV VLPs; in contrast, those with a measurable Kd gave a positive signal in the capture ELISA. Thus, some broadly cross-reactive epitopes in the VP1 protruding domain may be partially masked on intact particles. One MAb, NV23, was able to detect genogroup I, II, and IV VLPs from 16 genotypes tested by sandwich ELISA, and it successfully detected NoVs in stool samples positive by real-time reverse transcription-PCR when the threshold cycle (CT) value was <31. Biochemical analyses of MAb reactivity, including SPR analysis, identified NV23 as a broadly reactive ligand for application in norovirus diagnostic assays.
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Baijun
authors.initials: B
authors.lastname: Kou
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Sue E
authors.initials: SE
authors.lastname: Crawford
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Nadim J
authors.initials: NJ
authors.lastname: Ajami
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Rita
authors.initials: R
authors.lastname: Czakó
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Frederick H
authors.initials: FH
authors.lastname: Neill
authors.affiliation: Sakai City Institute of Public Health, Sakai, Japan.
authors.forename: Tomoyuki N
authors.initials: TN
authors.lastname: Tanaka
authors.affiliation: Department of Food Science and Nutrition, Himeji College of Hyogo, Himeji, Japan.
authors.forename: Noritoshi
authors.initials: N
authors.lastname: Kitamoto
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA Department of Pharmacology, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Timothy G
authors.initials: TG
authors.lastname: Palzkill
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA Department of Medicine, Baylor College of Medicine, Houston, Texas, USA.
authors.forename: Mary K
authors.initials: MK
authors.lastname: Estes
authors.affiliation: Department of Molecular Virology and Microbiology, Baylor College of Medicine, Houston, Texas, USA Department of Medicine, Baylor College of Medicine, Houston, Texas, USA ratmar@bcm.edu.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Atmar
mesh_terms: D000911:Antibodies, Monoclonal / Q000276:immunology*; D000914:Antibodies, Viral / Q000276:immunology*; D000915:Antibody Affinity; D015153:Blotting, Western; D017250:Caliciviridae Infections / Q000175:diagnosis / Q000821:virology; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D005243:Feces / Q000821:virology; D006801:Humans; D008969:Molecular Sequence Data; D029322:Norovirus / Q000276:immunology*; D017422:Sequence Analysis, DNA; D020349:Surface Plasmon Resonance; D022701:Virosomes / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D022701:Virosomes