title: Mutation tryptophan to leucine at position 222 of haemagglutinin could facilitate H3N2 influenza A virus infection in dogs.
abstract: An avian-like H3N2 influenza A virus (IAV) has recently caused sporadic canine influenza outbreaks in China and Korea, but the molecular mechanisms involved in the interspecies transmission of H3N2 IAV from avian to canine species are not well understood. Sequence analysis showed that residue 222 in haemagglutinin (HA) is predominantly tryptophan (W) in the closely related avian H3N2 IAV, but was leucine (L) in canine H3N2 IAV. In this study, reassortant viruses rH3N2-222L (canine-like) and rH3N2-222W (avian-like) with HA mutation L222W were generated using reverse genetics to evaluate the significance of the L222W mutation on receptor binding and host tropism of H3N2 IAV. Compared with rH3N2-222W, rH3N2-222L grew more rapidly in MDCK cells and had significantly higher infectivity in primary canine tracheal epithelial cells. Tissue-binding assays demonstrated that rH3N2-222L had a preference for canine tracheal tissues rather avian tracheal tissues, whereas rH3N2-222W favoured slightly avian rather canine tracheal tissues. Glycan microarray analysis suggested both rH3N2-222L and rH3N2-222W bound preferentially to α2,3-linked sialic acids. However, the rH3N2-222W had more than twofold less binding affinity than rH3N2-222L to a set of glycans with Neu5Aca2-3Galb1-4(Fuca-)-like or Neu5Aca2-3Galb1-3(Fuca-)-like structures. These data suggest the W to L mutation at position 222 of the HA could facilitate infection of H3N2 IAV in dogs, possibly by increasing the binding affinities of the HA to specific receptors with Neu5Aca2-3Galb1-4(Fuca-) or Neu5Aca2-3Galb1-3(Fuca-)-like structures that are present in dogs.
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Guohua
authors.initials: G
authors.lastname: Yang
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P.R. China.
authors.forename: Shoujun
authors.initials: S
authors.lastname: Li
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Sherry
authors.initials: S
authors.lastname: Blackmon
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Ye
authors.affiliation: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30307, USA.
authors.forename: Konrad C
authors.initials: KC
authors.lastname: Bradley
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Jim
authors.initials: J
authors.lastname: Cooley
authors.affiliation: Department of Biochemistry and the Glycomics Center, School of Medicine, Emory University, Atlanta, GA 30307, USA.
authors.forename: Dave
authors.initials: D
authors.lastname: Smith
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Larry
authors.initials: L
authors.lastname: Hanson
authors.affiliation: College of Veterinary Medicine, University of Minnesota, St Paul, MN 55108, USA.
authors.forename: Carol
authors.initials: C
authors.lastname: Cardona
authors.affiliation: Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA 30307, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Steinhauer
authors.affiliation: Department of Infectious Diseases, St Jude Children's Research Hospital, 262 Danny Thomas Place, Memphis, TN 38105, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Webby
authors.affiliation: College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, P.R. China.
authors.forename: Ming
authors.initials: M
authors.lastname: Liao
authors.affiliation: College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762, USA.
authors.forename: Xiu-Feng
authors.initials: XF
authors.lastname: Wan
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002460:Cell Line; D002681:China; D004283:Dog Diseases / Q000821:virology*; D004285:Dogs; D057809:HEK293 Cells; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D053122:Influenza A Virus, H3N2 Subtype / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D007930:Leucine / Q000235:genetics; D009154:Mutation; D009976:Orthomyxoviridae Infections / Q000662:veterinary* / Q000821:virology; D012794:Sialic Acids / Q000737:chemistry / Q000378:metabolism; D014364:Tryptophan / Q000235:genetics
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D012794:Sialic Acids; D014364:Tryptophan; D007930:Leucine