Influenza Hemagglutinin Antigen H3N2 Subtype A Virus Protein (HA)

The hemagglutinin (HA) antigen of the influenza A virus subtype H3N2 is a surface glycoprotein crucial for viral entry. It mediates binding to host cell receptors containing sialic acid, initiating infection through membrane fusion. HA is a trimeric protein, with each monomer composed of HA1 and HA2 subunits. Antigenic drift, especially in the receptor-binding site, and glycan shielding contribute to immune evasion, necessitating frequent updates to vaccine strains. HA is a primary target for neutralizing antibodies and antiviral interventions. Mutations at positions 226 and 228 in HA are key determinants of host range and receptor specificity.

Other names

HemagglutininH3N2 HemagglutininHA H3N2

Facilitates viral entry into host cells by binding to sialic acid receptors and mediating membrane fusion. Neutralizing antibodies against HA prevent binding or fusion.