Hemagglutinin antigen of Influenza A H1N1

Hemagglutinin (HA) is a glycoprotein found on the surface of the influenza A H1N1 virus. It mediates viral entry into host cells by binding to sialic acid receptors and facilitating fusion between the viral envelope and the host cell membrane. HA is a major antigen and the primary target for neutralizing antibodies, making it crucial for vaccine development. The HA protein is a homotrimer composed of HA1 and HA2 subunits, formed through proteolytic cleavage of a precursor protein. Antigenic drift and shift result in mutations that allow the virus to evade pre-existing immunity, posing a challenge for vaccine effectiveness. Broadly neutralizing antibodies targeting conserved regions of HA are a focus for universal influenza vaccine research.

Other names

HAH1N1 HemagglutininInfluenza A Hemagglutinin

Receptor binding to sialic acid, membrane fusion mediated by conformational change at low pH.