Repeated vaccination with homologous influenza hemagglutinin broadens human antibody responses to unmatched flu viruses.

ABSTRACT: The ongoing diversification of influenza virus necessitates annual vaccine updating. The vaccine antigen, the viral spike protein hemagglutinin (HA), tends to elicit strain-specific neutralizing activity, predicting that sequential immunization with the same HA strain will boost antibodies with narrow coverage. However, repeated vaccination with homologous SARS-CoV-2 vaccine eventually elicits neutralizing activity against highly unmatched variants, questioning this immunological premise. We evaluated a longitudinal influenza vaccine cohort, where each year the subjects received the same, novel H1N1 2009 pandemic vaccine strain. Repeated vaccination gradually enhanced receptor-blocking antibodies (HAI) to highly unmatched H1N1 strains within individuals with no initial memory recall agains

SUBMITTER: Deng Y 

PROVIDER: S-EPMC12614894 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature