title: Quantitative serology assays for determination of antibody responses to Ebola virus glycoprotein and matrix protein in nonhuman primates and humans.
abstract: The West Africa Ebola virus disease (EVD) outbreak has reached unprecedented magnitude and caused worldwide concerns for the spread of this deadly virus. Recent findings in nonhuman primates (NHPs) demonstrate that antibodies can be protective against EVD. However, the role of antibody response in vaccine-mediated protection is not fully understood. To address these questions quantitative serology assays are needed for measurement of the antibody response to key Ebola virus (EBOV) proteins. Serology enzyme-linked immunosorbent assays (ELISA's), using a reference detection antibody, were developed in order to standardize the quantitation of antibody levels in vaccinated NHPs or in humans exposed to EBOV or immunized with an EBOV vaccine. Critical reagents were generated to support the development of the serology ELISAs. Recombinant EBOV matrix protein (VP40) was expressed in Escherichia coli and purified. Two variants of the glycoprotein (GP), the ectodomain lacking the transmembrane domain (GPΔTM), and an engineered GP lacking the mucin-like domain (GPΔmuc) were expressed and purified from mammalian cell systems. Using these proteins, three ELISA methods were developed and optimized for reproducibility and robustness, including stability testing of critical reagents. The assay was used to determine the antibody response against VP40, GPΔTM, and GPΔmuc in a NHP vaccine study using EBOV virus-like particles (VLP) vaccine expressing GP, VP40 and the nucleoprotein. Additionally, these ELISAs were used to successfully detect antibody responses to VP40, GPΔTM and GPΔmuc in human sera from EBOV infected individuals.
authors.affiliation: Integrated BioTherapeutics, Inc., Gaithersburg, MD 20878, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Vu
authors.affiliation: Integrated BioTherapeutics, Inc., Gaithersburg, MD 20878, USA.
authors.forename: Sergey
authors.initials: S
authors.lastname: Shulenin
authors.affiliation: Public Health Agency of Canada, Winnipeg, Canada.
authors.forename: Allen
authors.initials: A
authors.lastname: Grolla
authors.affiliation: Public Health Agency of Canada, Winnipeg, Canada.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Audet
authors.affiliation: Public Health Agency of Canada, Winnipeg, Canada.
authors.forename: Shihua
authors.initials: S
authors.lastname: He
authors.affiliation: Public Health Agency of Canada, Winnipeg, Canada.
authors.forename: Gary
authors.initials: G
authors.lastname: Kobinger
authors.affiliation: Integrated BioTherapeutics, Inc., Gaithersburg, MD 20878, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Unfer
authors.affiliation: Integrated BioTherapeutics, Inc., Gaithersburg, MD 20878, USA.
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Warfield
authors.affiliation: Integrated BioTherapeutics, Inc., Gaithersburg, MD 20878, USA.
authors.forename: M Javad
authors.initials: MJ
authors.lastname: Aman
authors.affiliation: Integrated BioTherapeutics, Inc., Gaithersburg, MD 20878, USA. Electronic address: rick@integratedbiotherapeutics.com.
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Holtsberg
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood* / Q000276:immunology; D000917:Antibody Formation; D004195:Disease Models, Animal; D046129:Ebola Vaccines / Q000276:immunology* / Q000494:pharmacology; D029043:Ebolavirus / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006023:Glycoproteins / Q000097:blood / Q000276:immunology*; D057809:HEK293 Cells; D019142:Hemorrhagic Fever, Ebola / Q000097:blood / Q000276:immunology* / Q000821:virology; D006801:Humans; D008251:Macaca; D008252:Macaca fascicularis; D008297:Male; D015202:Protein Engineering; D015203:Reproducibility of Results; D014763:Viral Matrix Proteins / Q000097:blood / Q000235:genetics / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D046129:Ebola Vaccines; D006023:Glycoproteins; C080981:VP40 protein, virus; D014763:Viral Matrix Proteins
keywords: Antibodies; Ebola virus; Human; Nonhuman primate; Serology ELISA; Vaccine