title: Assessment of influenza A neuraminidase (subtype N1) potency by ELISA.
abstract: Antibodies that inhibit neuraminidase (NA) activity of influenza virus provide resistance against disease and have been associated with milder epidemics. Although studies have demonstrated a correlation between NA inhibition antibody titers and vaccine efficacy, neither the quantity nor form of NA is measured in seasonal and pandemic influenza vaccines. In this report, we describe development of enzyme-linked immunosorbent assays (ELISAs) that are suitable for quantitation of the native form of NA of subtype N1. The assays use mouse monoclonal antibodies (mAbs) 1H5 and CD6 to capture NAs of viruses, and a different mAb 4E9 to detect bound antigen. The 1H5-capture ELISA detects NAs of seasonal and pandemic H1N1 viruses as well as H5N1 viruses and has a limit of quantitation (LOQ) of 5.5ng/mL for seasonal H1N1A/Brisbane/59/2007 NA. The CD6-capture ELISA is specific for NA of the 2009 pandemic viruses with a LOQ of 67ng/mL for A/California/07/2009 NA. The ELISA signals in both assays are proportional to NA enzymatic activity and correlate with NA immunogenicity. The ELISAs we describe may expedite the development of NA-based influenza vaccines by providing a practical assay to measure NA potency.
authors.affiliation: Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, United States.
authors.forename: Hongquan
authors.initials: H
authors.lastname: Wan
authors.affiliation: Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, United States.
authors.forename: Ishrat
authors.initials: I
authors.lastname: Sultana
authors.affiliation: Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, United States.
authors.forename: Laura K
authors.initials: LK
authors.lastname: Couzens
authors.affiliation: Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, United States.
authors.forename: Samuel
authors.initials: S
authors.lastname: Mindaye
authors.affiliation: Division of Viral Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, MD 20993, United States. Electronic address: maryna.eichelberger@fda.hhs.gov.
authors.forename: Maryna C
authors.initials: MC
authors.lastname: Eichelberger
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D009980:Influenza A virus / Q000201:enzymology* / Q000276:immunology; D051379:Mice; D009439:Neuraminidase / Q000032:analysis* / Q000276:immunology; D014764:Viral Proteins / Q000032:analysis* / Q000276:immunology
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D014764:Viral Proteins; C487630:NA protein, influenza A virus; D009439:Neuraminidase
keywords: ELISA; Influenza; Monoclonal antibody; Neuraminidase; Potency