Is It Possible to Develop a “Universal” Influenza Virus Vaccine?

Abstract

Current influenzavaccines preferentially generate B-cell responses to the variable hemagglu- tinin (HA) head. Focusing vaccine-induced antibody responses on epitopes in the conserved HA stem may provide better protection against future drifted and pandemic strains. Under- standing the basis for the dominantHAhead and subdominantHAstem-specific responses at the level of B-cell activation and differentiation will be critical for designing vaccines that induce sustained stem-specific responses. Identifying antibody lineages with broad neutral- izing activity against influenza Aviruses and defining the structural mode of recognition for germline precursors of those antibodies will also guide future immunogen design.