title: Sialic acid content in human saliva and anti-influenza activity against human and avian influenza viruses.
abstract: It was shown previously that human saliva has higher antiviral activity against human influenza viruses than against H5N1 highly pathogenic avian influenza viruses, and that the major anti-influenza activity was associated with sialic-acid-containing molecules. To further characterize the differential susceptibility to saliva among influenza viruses, seasonal influenza A and B virus, pandemic H1N1 virus, and 15 subtypes of avian influenza virus were tested for their susceptibility to human and chicken saliva. Human saliva showed higher hemagglutination inhibition (HI) and neutralization (NT) titers against seasonal influenza A virus and the pandemic H1N1 viruses than against influenza B virus and most avian influenza viruses, except for H9N2 and H12N9 avian influenza viruses, which showed high HI and NT titers. To understand the nature of sialic-acid-containing anti-influenza factors in human saliva, α2,3- and α2,6-linked sialic acid was measured in human saliva samples using a lectin binding and dot blot assay. α2,6-linked sialic acid was found to be more abundant than α2,3-linked sialic acid, and a seasonal H1N1 influenza virus bound more efficiently to human saliva than an H5N1 virus in a dot blot analysis. These data indicated that human saliva contains the sialic acid type corresponding to the binding preference of seasonal influenza viruses.
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok, 10700, Thailand.
authors.forename: Nattavatchara
authors.initials: N
authors.lastname: Limsuwat
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok, 10700, Thailand.
authors.forename: Ornpreya
authors.initials: O
authors.lastname: Suptawiwat
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok, 10700, Thailand.
authors.forename: Chompunuch
authors.initials: C
authors.lastname: Boonarkart
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok, 10700, Thailand.
authors.forename: Pilaipan
authors.initials: P
authors.lastname: Puthavathana
authors.affiliation: Faculty of Veterinary Science, Mahidol University, Bangkok, Thailand.
authors.forename: Witthawat
authors.initials: W
authors.lastname: Wiriyarat
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, 2 Prannok Road, Bangkok, 10700, Thailand. prasert.aue@mahidol.ac.th.|Institute of Molecular Biosciences, Mahidol University, Bangkok, Thailand. prasert.aue@mahidol.ac.th.
authors.forename: Prasert
authors.initials: P
authors.lastname: Auewarakul
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry* / Q000378:metabolism*; D002645:Chickens; D006801:Humans; D009980:Influenza A virus / Q000187:drug effects* / Q000502:physiology; D009981:Influenza B virus / Q000187:drug effects* / Q000502:physiology; D005585:Influenza in Birds; D019158:N-Acetylneuraminic Acid / Q000032:analysis*; D012463:Saliva / Q000737:chemistry* / Q000378:metabolism*
chemical_list: D000998:Antiviral Agents; D019158:N-Acetylneuraminic Acid