LAUSR

Influenza Seasonal influenza vaccines have been recommended for decades, but studies focused on antigen-specific lymphocytes in humans are sparse. Koutsakos et al. examined longitudinal samples of influenza-vaccinated individuals to determine what responses generate protective immunity. Vaccination could induce circulating T follicular helper memory cells, antibody-secreting cells, and memory B cells, but it did not seem to affect other types of lymphocytes. Existing antibodies against influenza at the time of vaccination dampened these responses. The authors probed different tissues for influenza memory B cells, which they found outside the circulation. Better targeting of these cells might improve influenza vaccine efficacy. Sci. Transl. Med. 10 , eaan8405 (2018).