sequence analysis and phylogenetic study of hemagglutinin (ha) gene of h9n2 subtype of avian influenza virus isolates (outbreaks of 1998-2002) in tehran province (iran) were studied. two sets of forward and reverse primers in highly conserved regions, based on sequences of ha gene in genbank, were designed. pcr products of a 430-bp fragment of 16 isolates were sequenced and then were aligned wi...

D222G/N substitutions in A(H1N1)pdm09 hemagglutinin may be associated with increased binding of viruses causing low respiratory tract infections and human pathogenesis. We assessed the impact of such substitutions on the balance between hemagglutinin binding and neuraminidase cleavage, viral growth and in vivo virulence.Seven viruses with differing polymorphisms at codon 222 (2 with D, 3 G, 1 N...

We have used the technique of DNA-mediated gene transfer to examine cytotoxic T lymphocyte (CTL) recognition of the product of the cloned A/JAPAN/305/57 hemagglutinin (HA) gene in murine (L929) cells. Using both heterogeneous and homogeneous (clonal) populations of type A influenza-specific CTL, we have demonstrated that the HA molecule can serve as a target antigen for both the subtype-specifi...

Virus H9N2 has become the most common subtype of low pathogenic avian influenza (LPAI) in poultry and shows ability to infect humans. One important factors triggering virus ​​pandemic is live bird market (LBM). The acts as an internal gene donor other subtypes, such H5N1, H5N2, H7N9, H10N8, This study was conducted detect presence molecular characteristics hemagglutinin fragment at cleavage sit...

introduction: in recent years, influenza viruses have caused moderate to severe infections all around the world while so far there is no influenza vaccine that can protect people with only one dose of injection. in this regard, producing a universal vaccine based on virus-like-particles (vlp) could be an ideal approach.  methods: in this study, the full-length orf of influenza hemagglutinin (ha...

We assessed whether influenza virus hemagglutinin stalk-based immunity protects ferrets against aerosol-transmitted H1N1 influenza virus infection. Immunization of ferrets by a universal influenza virus vaccine strategy based on viral vectors expressing chimeric hemagglutinin constructs induced stalk-specific antibody responses. Stalk-immunized ferrets were cohoused with H1N1-infected ferrets u...

During two winter seasons between 1999 and 2001, seven strains of influenza virus were isolated from healthy pigs in Saitama Prefecture, Japan. All isolates were identified as A (H1N2) reassortant viruses. Genetic and phylogenetic analyses indicated that they had classical swine-like hemagglutinin (HA) and internal genes, and relatively early human-like neuraminidase (NA) gene. The HA and NA ge...

Electrically controllable deoxyribonuclic acid (DNA) nanolevers are used to investigate the binding interaction between Influenza A/Aichi/2/1968 and peptide called “PeB”, which specifically binds viral surface protein hemagglutinin. PeB is immobilized on gold electrodes of a “switchSENSE” biochip by conjugation DNA-strands that hybridized complementary anchors. The surface-tethered DNA strand c...

Significant genetic variability in the head region of the influenza A hemagglutinin, the main target of current vaccines, makes it challenging to develop a long-lived seasonal influenza prophylaxis. Vaccines based on the conserved hemagglutinin stalk domain might provide broader cross-reactive immunity. However, this region of the hemagglutinin is immunosubdominant to the head region. Peptide-b...

The 1918 influenza pandemic caused more than 40 million deaths and likely resulted from the introduction and adaptation of a novel avian-like virus. Influenza A virus hemagglutinins are important in host switching and virulence. Avian-adapted influenza virus hemagglutinins bind sialic acid receptors linked via alpha2-3 glycosidic bonds, while human-adapted hemagglutinins bind alpha2-6 receptors...