Format

Send to

Choose Destination
Int Immunol. 2018 Aug 30;30(9):397-402. doi: 10.1093/intimm/dxy020.

The critical role of Bach2 in regulating type 2 chronic airway inflammation.

Author information

1
Department of Immunology, Graduate School of Medicine, Ehime University, Shitsukawa, Toon, Ehime, Japan.
2
Translational Research Center, Ehime University Hospital, Shitsukawa, Toon, Ehime, Japan.
3
Division of Immune Regulation, Department of Proteo-Inovation, Proteo-Science Center, Ehime University, Toon City, Ehime, Japan.

Abstract

Although Bach2 (broad complex-tramtrack-bric a brac and Cap'n'collar homology 2) plays an important role in regulating Th2 cell differentiation and type 2 immune responses, the underlying molecular mechanisms remain unclear. Our current studies demonstrate that Bach2 associates with Batf (basic leucine zipper transcription factor ATF-like) family transcription factors and binds to the regulatory regions of the Th2 cytokine gene loci. The Bach2-Batf complex antagonizes the recruitment of the interferon regulatory factor 4 (Irf4)-containing Batf complex to activator protein 1 (AP-1) motifs in the Th2 cytokine gene locus and suppresses Th2 cytokine production and/or Th2 cell differentiation. The deletion of Batf ameliorated the spontaneous development of type 2 airway inflammation that is found in mice with Bach2 deficiency specifically in T cells. Interestingly, Bach2 regulates Batf and Batf3 expression via two distinct pathways. First, the Bach2-Batf complex directly binds to the Batf and Batf3 gene loci and reduces transcription by interfering with the Batf-Irf4 complex. Second, Bach2 suppresses interleukin 4 (IL-4)-induced augmentation of Batf and Batf3 expression through the regulation of IL-4 production. These findings suggest that IL-4 and Batf family transcription factors form a positive feedback amplification loop to induce Th2 cell differentiation and that Bach2-Batf interactions block the formation of this amplification loop. Furthermore, we found that reductions in Bach2 confer an innate immunological function on CD4 T cells to induce antigen-independent cytokine production. Some Bach2-deficient lung CD4 T cells showed characteristic features similar to pathogenic Th2 cells, including IL-33 receptor expression and IL-33-dependent Th2 cytokine production. These results suggest a critical role for Bach2 in regulating Th2 cell differentiation and the subsequent onset of chronic type 2 inflammation.

PMID:
29529253
DOI:
10.1093/intimm/dxy020
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center