BCR and influenza: We used TyCHE to investigate a published dataset of single-cell BCR sequences from longitudinal blood, lymph node, and bone marrow samples obtained from two human adults following seasonal influenza vaccination over the 2018/2019 and 2019/2020 flu seasons (Fig. 5).30 Among these data, we identified 8 measurably evolving lineages that contained GC B cells sampled after each vaccination, and were experimentally confirmed to bind to influenza antigens using monoclonal antibodies.