Eosinophils control the resolution of inflammation and draining lymph node hypertrophy through the proresolving mediators and CXCL13 pathway in mice.

ABSTRACT: Resolution of inflammation is critical to restoration of tissue function after an inflammatory response. We previously demonstrated that 12/15-lipoxygenase (12/15-LOX)-expressing eosinophils contribute to this process in murine zymosan-induced peritonitis. In this study, eosinophils promoted resolution by regulating expression of macrophage CXCL13. Microarray analysis revealed that eosinophils significantly increased (?3-fold) the expression of macrophage CXCL13 by a 12/15-LOX-dependent mechanism. CXCL13 depletion caused a resolution defect, with the reduced appearance of phagocytes carrying engulfed zymosan in the draining lymph nodes. Inflamed lymph node hypertrophy, a critical feature of the resolution process, was reduced by ?60% in eosinophil-deficient mice, and adoptive transfer of eosinophils or administration of CXCL13 corrected this defect. Administration of the 12/15-LOX-derived mediator lipoxin A4 (LXA4) increased the expression of CXCL13 and restored the defect of lymph node hypertrophy in eosinophil-deficient mice. These results demonstrate that eosinophils control the resolution of inflammation and draining lymph node hypertrophy through proresolving lipid mediators and the CXCL13 pathway in mice.

SUBMITTER: Tani Y 

PROVIDER: S-EPMC5395732 | biostudies-literature | 2014 Sep

REPOSITORIES: biostudies-literature