Article

Innate Response Activator B Cells Protect Against Microbial Sepsis

Center for Systems Biology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA.
Science (Impact Factor: 31.48). 02/2012; 335(6068):597-601. DOI: 10.1126/science.1215173
Source: PubMed

ABSTRACT 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.

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