A Neutrophil - B-cell Axis Governs Disease Tolerance During Sepsis Via Cxcr4

Sepsis is a life-threatening condition characterized by uncontrolled systemic inflammation and coagulation, leading to multi-organ failure. Therapeutic options to prevent sepsis-associated immunopathology remain scarce. Here, we established a model of long-lasting disease tolerance during severe sepsis, manifested by diminished immunothrombosis and organ damage in spite of a high pathogen burden. We found that, both neutrophils and B cells emerged as key regulators of tissue integrity. Enduring changes in the transcriptional profile of neutrophils, included upregulated Cxcr4 expression in protected, tolerant hosts. Neutrophil Cxcr4 upregulation required the presence of B cells, suggesting that B cells promoted tissue tolerance by suppressing tissue damaging properties of neutrophils. Finally, therapeutic administration of a Cxcr4 agonist successfully promoted tissue tolerance and prevented liver damage during sepsis. Our findings highlight the importance of a critical B-cell/neutrophil interaction during sepsis and establish neutrophil Cxcr4 activation as a potential means to promote disease tolerance during sepsis. Summary We show that a B cell/neutrophil interaction in the bone marrow facilitates tissue tolerance during severe sepsis. By affecting neutrophil Cxcr4 expression, B cells can impact neutrophil effector functions. Finally, therapeutic activation of Cxcr4 successfully promoted tissue tolerance and prevented liver damage during sepsis. ### Competing Interest Statement The authors have declared no competing interest. * ALAT : Alanine aminotransferase ASAT : Apartate aminotransferase Cxcr4 : CXC-motive chemokine receptor 4 DEG : differentially expressed gene E. coli : Escherichia coli FO B cell : follicular B cell IFNAR : interferon-α/β receptor i.p. : intraperitoneally IRA B cell : innate response activator B cell i.v. : intravenously LPS : Lipopolysaccharide MZ B cell : marginal zone B cell PLF : peritoneal lavage fluid p.i. : post infection TLR : Toll-like receptor