A TNF-α-CCL20-CCR6 axis regulates Nod1-induced B cell responses

J Immunol. 2014 Mar 15;192(6):2787-99. doi: 10.4049/jimmunol.1203310. Epub 2014 Feb 17.

Abstract

Innate immune responses provoke the accumulation of leukocytes at sites of inflammation. In addition to monocytes and granulocytes, B cells also participate in antimicrobial innate immune responses; however, the mechanisms for accumulation of B cells to sites of inflammation are not well understood. To study B cell accumulation following systemic inflammation, we used a model synthetic ligand that stimulates a specific pattern recognition molecule, nucleotide-binding oligomerization domain-containing protein 1 (Nod1). Upon exposure to Nod1 agonists, both B cells and neutrophils rapidly accumulate within the spleen, and dendritic cells migrate into the periarterial lymphoid sheath. Nod1 stimulation led to a marked increase in several chemokines within the spleen, including CXCL13, CCL2, and CCL20. Whereas the lymphotoxin pathway was critical for the induction of the B cell chemoattractant CXCL13 in response to Nod1 agonists, B cell accumulation within the spleen following Nod1-induced systemic inflammation was independent of the lymphotoxin pathway. In contrast, a CCR6/CCL20 chemokine loop instructed rapid increase of B cells in the spleen in response to systemic administration of Nod1 agonists in a TNF-α-dependent manner. Moreover, CCR6 was required to regulate Nod1-mediated B cell responses. These results reveal a novel mechanism of B cells during inflammation and shed light on how B cells participate in innate immune responses to microbial stimulation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • B-Lymphocytes / drug effects
  • B-Lymphocytes / immunology*
  • B-Lymphocytes / metabolism
  • Bone Marrow Cells / drug effects
  • Bone Marrow Cells / immunology
  • Bone Marrow Cells / metabolism
  • Bone Marrow Transplantation / methods
  • Cell Line
  • Cells, Cultured
  • Chemokine CCL20 / immunology*
  • Chemokine CCL20 / metabolism
  • Diaminopimelic Acid / analogs & derivatives
  • Diaminopimelic Acid / pharmacology
  • Female
  • Flow Cytometry
  • Lymphocyte Count
  • Lymphoid Tissue / cytology
  • Lymphoid Tissue / immunology
  • Lymphoid Tissue / metabolism
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microscopy, Fluorescence
  • Neutrophils / drug effects
  • Neutrophils / immunology
  • Neutrophils / metabolism
  • Nod1 Signaling Adaptor Protein / genetics
  • Nod1 Signaling Adaptor Protein / immunology*
  • Nod1 Signaling Adaptor Protein / metabolism
  • Receptors, CCR6 / genetics
  • Receptors, CCR6 / immunology*
  • Receptors, CCR6 / metabolism
  • Spleen / cytology
  • Spleen / immunology
  • Spleen / metabolism
  • Transplantation Chimera / blood
  • Tumor Necrosis Factor-alpha / genetics
  • Tumor Necrosis Factor-alpha / immunology*
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • CCR6 protein, mouse
  • Chemokine CCL20
  • Nod1 Signaling Adaptor Protein
  • Nod1 protein, mouse
  • Receptors, CCR6
  • Tumor Necrosis Factor-alpha
  • Diaminopimelic Acid
  • FK 156