Sutton, HarryAye, RachealIdris, AzzaVistein, RachelNduati, Eunice WKai, OscarMwacharo, JedidaLi, SeanGao, XinAndrews, DanKoutsakos, MariosNguyen, Thi H ONekrasov, MaximMilburn, PeterEltahla, Auda ABerry, Andrea AChakravarty, SumanaCockburn, Ian2023-07-112023-07-112211-1247http://hdl.handle.net/1885/294111The diversity of circulating human B cells is unknown. We use single-cell RNA sequencing (RNA-seq) to examine the diversity of both antigen-specific and total B cells in healthy subjects and malaria-exposed individuals. This reveals two B cell lineages: a classical lineage of activated and resting memory B cells and an alternative lineage, which includes previously described atypical B cells. Although atypical B cells have previously been associated with disease states, the alternative lineage is common in healthy controls, as well as malaria-exposed individuals. We further track Plasmodium-specific B cells after malaria vaccination in naive volunteers. We find that alternative lineage cells are primed after the initial immunization and respond to booster doses. However, alternative lineage cells develop an atypical phenotype with repeated boosts. The data highlight that atypical cells are part of a wider alternative lineage of B cells that are a normal component of healthy immune responses.Production and characterization of PfSPZ vaccine were supported in part by National Institute of Allergy and Infectious Diseases Small Business Innovation Research Grants 5R44AI055229-11 (to S.L.H.), 5R44AI058499-08 (to S.L.H.), and 5R44AI058375-08 (to S.L.H.). F.M.N. was supported by an MRC/DFID African Research Leadership Award (MR/P020321/1) and a Senior Fellowship from the European and Developing Countries Clinical Trial Partnership (TMA2016SF-1513). R.A. was supported by the African Academy of Sciences through the DELTAS Africa Initiative (DEL-15-003).application/pdfen-AU© 2021 The authorshttp://creativecommons.org/licenses/ by-nc-nd/4.0/B cell memoryatypical B cellsalternative B cell lineagemalariasporozoitevaccinationsingle cell RNA-seqCITE-seq202110.1016/j.celrep.2020.1086842022-05-08Creative Commons Attribution licence