Figure 3.

Conventional antigenic sites and recently identified epitopes. (A) The five major antigenic sites A-E on H3N2 HA are shown. (B) There is an accumulation of glycosylation sites during human H3N2 evolution. While many antigenic sites have now been masked by glycans (yellow), antigenic site B (blue) remains exposed due to its proximity to the RBS, making it immunodominant in recent human H3N2 strains [95,96]. (C) Broadly neutralizing epitopes that have been identified in the past decade are shown. (D) A recently identified trimeric interface epitope is illustrated.