Hemagglutinin (HA) of the influenza virus plays a crucial role in the early stage of the viral life cycle by binding to sialic acid on the surface of host epithelial cells and mediating fusion between virus envelope and endosome membrane for the release of viral genomes into the cytoplasm. To initiate virus fusion, endosome pH is lowered by acidification causing an irreversible conformational c...

Hemagglutinin (HA) is essential for Influenza A virus infection, but its diversity of subtypes presents an obstacle to developing broad-spectrum HA inhibitors. In this study, we investigated the molecular mechanisms by which poly-galloyl glucose (pGG) analogs inhibit influenza hemagglutinin (HA) in vitro and in silico. We found that (1) star-shaped pGG analogs exhibit HA-inhibition activity by ...

The present mini-review aims first at an introduction to two thermodynamic essentials of the binding between the influenza A virus hemagglutinin (HA) and the cell surface receptor sialoside, (1) the equilibrium 1:1 binding of the HA with the sialoside, (2) the polyvalent effect of the HA binding to the polyvalent sialoside. Second, the review introduces the fragment molecular orbital (FMO) stud...

The influenza glycoprotein hemagglutinin (HA) plays crucial roles in the early stage of virus infection, including receptor binding and membrane fusion. Therefore, HA is a potential target for developing anti-influenza drugs. Recently, we characterized a novel inhibitor of highly pathogenic H5N1 influenza virus, CL-385319, which specifically inhibits HA-mediated viral entry. Studies presented h...

Traditionally, immunoglobulin A (IgA) was thought to neutralize virus by forming complexes with viral attachment proteins, blocking attachment of virions to host epithelial cells. Recently we have proposed an intracellular action for dimeric IgA, which is actively transported through epithelial cells by the polymeric immunoglobulin receptor (pIgR), in that it may be able to bind to newly synthe...

to a target cell occurs through multiple simultaneous interactions between hemagglutinin (HA) and sialic acid (SA)Ðthis is an example of a polyvalent interaction. The attachment can be blocked effectively by an inhibitor that is itself polyvalent.

Influenza virus entry is mediated by the receptor binding domain (RBD) of its spike, the hemagglutinin (HA). Adaptation of avian viruses to humans is associated with HA specificity for alpha2,6- rather than alpha2,3-linked sialic acid (SA) receptors. Here, we define mutations in influenza A subtype H5N1 (avian) HA that alter its specificity for SA either by decreasing alpha2,3- or increasing al...

A recombinant baculovirus harboring the hemagglutinin (HA) gene of African swine fever virus, with homology to the T-lymphocyte surface antigen CD2, was constructed. The efficient expression of the HA gene was determined by immunofluorescence and Western blot studies on insect cells infected with the recombinant baculovirus. The baculovirus-expressed HA showed hemadsorption and erythrocyte-aggl...

Biofilm production is thought to be a crucial factor in the ability of Staphylococcus epidermidis to produce a biomaterial-based infection. A rat central venous catheter (CVC)-associated infection model was used to assess the importance of biofilm production, mediated by polysaccharide intercellular adhesin/hemagglutinin (PIA/HA), in the pathogenesis of intravascular catheter-associated infecti...