biostudies-literatureRauch PJNCRR NIH HHSNHLBI NIH HHSNCI NIH HHSPHS HHS597-601https://www.ebi.ac.uk/biostudies/studies/S-EPMC3279743biostudies-literatureUnknown335(6068)Recognition and clearance of a bacterial infection are a fundamental properties of innate immunity. Here, we describe an effector B cell population that protects against microbial sepsis. Innate response activator (IRA) B cells are phenotypically and functionally distinct, develop and diverge from B1a B cells, depend on pattern-recognition receptors, and produce granulocyte-macrophage colony-stimulating factor. Specific deletion of IRA B cell activity impairs bacterial clearance, elicits a cytokine storm, and precipitates septic shock. These observations enrich our understanding of innate immunity, position IRA B cells as gatekeepers of bacterial infection, and identify new treatment avenues for infectious diseases.Science (New York, N.Y.)Innate response activator B cells protect against microbial sepsis.PMC3279743P50 CA086355-11R24 CA692461R01HL095612P50 CA086355P50 CA86355P01-A154904S10 RR026360U01 HL080731R01 HL095612R01 HL095612-03U01 HL080731-04P01 CA069246Etzrodt MNahrendorf MWeber GFWeissleder RRobbins CSRauch PJWaring MTChudnovskiy ATheurl IHilgendorf IChicoine ATPittet MJSwirski FKGorbatov RIwamoto YMouded MFigueiredo JLTiglao EfalseInnate response activator B cells protect against microbial sepsis.Recognition and clearance of a bacterial infection are a fundamental properties of innate immunity. Here, we describe an effector B cell population that protects against microbial sepsis. Innate response activator (IRA) B cells are phenotypically and functionally distinct, develop and diverge from B1a B cells, depend on pattern-recognition receptors, and produce granulocyte-macrophage colony-stimulating factor. Specific deletion of IRA B cell activity impairs bacterial clearance, elicits a cytokine storm, and precipitates septic shock. These observations enrich our understanding of innate immunity, position IRA B cells as gatekeepers of bacterial infection, and identify new treatment avenues for infectious diseases.2012-01-01T00:00:00Z2012 Feb2020-11-07T08:41:02Z2019-03-27T00:49:10ZS-EPMC32797432224573810.1126/science.1215173