title: Pre-existing cross-reactive antibodies to avian influenza H5N1 and 2009 pandemic H1N1 in US military personnel.
abstract: We studied cross-reactive antibodies against avian influenza H5N1 and 2009 pandemic (p) H1N1 in 200 serum samples from US military personnel collected before the H1N1 pandemic. Assays used to measure antibodies against viral proteins involved in protection included a hemagglutination inhibition (HI) assay and a neuraminidase inhibition (NI) assay. Viral neutralization by antibodies against avian influenza H5N1 and 2009 pH1N1 was assessed by influenza (H5) pseudotyped lentiviral particle-based and H1N1 microneutralization assays. Some US military personnel had cross-neutralizing antibodies against H5N1 (14%) and 2009 pH1N1 (16.5%). The odds of having cross-neutralizing antibodies against 2009 pH1N1 were 4.4 times higher in subjects receiving more than five inactivated whole influenza virus vaccinations than those subjects with no record of vaccination. Although unclear if the result of prior vaccination or disease exposure, these pre-existing antibodies may prevent or reduce disease severity.
authors.affiliation: Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand; National Center for Genetic Engineering and Biotechnology, Pathum Thani, Thailand; Department of Microbiology, Faculty of Science, Mahidol University, Bangkok, Thailand; Department of Dentistry, Chulalongkorn University, Bangkok, Thailand; Hong Kong University-Pasteur Research Center, Hong Kong.
authors.forename: Sathit
authors.initials: S
authors.lastname: Pichyangkul
authors.forename: Somporn
authors.initials: S
authors.lastname: Krasaesub
authors.forename: Anan
authors.initials: A
authors.lastname: Jongkaewwattana
authors.forename: Arunee
authors.initials: A
authors.lastname: Thitithanyanont
authors.forename: Suwimon
authors.initials: S
authors.lastname: Wiboon-Ut
authors.forename: Kosol
authors.initials: K
authors.lastname: Yongvanitchit
authors.forename: Amporn
authors.initials: A
authors.lastname: Limsalakpetch
authors.forename: Utaiwan
authors.initials: U
authors.lastname: Kum-Arb
authors.forename: Duangrat
authors.initials: D
authors.lastname: Mongkolsirichaikul
authors.forename: Nuanpan
authors.initials: N
authors.lastname: Khemnu
authors.forename: Rangsini
authors.initials: R
authors.lastname: Mahanonda
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Garcia
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Mason
authors.forename: Douglas S
authors.initials: DS
authors.lastname: Walsh
authors.forename: David L
authors.initials: DL
authors.lastname: Saunders
mesh_terms: D000328:Adult; D000368:Aged; D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral / Q000097:blood*; D005260:Female; D006801:Humans; D053118:Influenza A Virus, H1N1 Subtype / Q000276:immunology*; D053124:Influenza A Virus, H5N1 Subtype / Q000276:immunology*; D007251:Influenza, Human / Q000097:blood / Q000276:immunology / Q000821:virology*; D008297:Male; D008875:Middle Aged; D008889:Military Personnel; D009500:Neutralization Tests; D016017:Odds Ratio; D014481:United States
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral