Antibody repertoires that converge upon influenza virus infection

In this study, we analyzed changes in antibody diversity and estimated the convergent sequences of antibody clones upon influenza virus infection in a mouse model using bulk repertoire analysis of antibody heavy-chain complementarity-determining region 3 (CDRH3) sequences. A decrease in the diversity of the antibody repertoire was observed upon viral infection, along with an increase in neutralizing antibody titers. Using background signal subtraction, we identified several convergent spots of sequences induced upon influenza virus infection on the kernel density estimation map. Most of these repertoires were detected more frequently in infected mice than in uninfected control mice, suggesting that infection-specific antibody sequences can be extracted using this method. More accurate extraction of antigen- or infection-specific repertoire information is a useful tool for future vaccine evaluation.