Lymphotoxin-beta receptor activation on macrophages ameliorates acute DSS-induced intestinal inflammation in a

Nadin Wimmer1, Barbara Huber, Anja K Wege

  • 1Institute of Immunology, University of Regensburg, 93053 Regensburg, Germany.

Molecular Immunology
|March 23, 2012
PubMed

Insights

LTβR activation on macrophages is crucial for controlling intestinal inflammation. This pathway, involving TRIM30α, down-regulates inflammatory responses, as shown in DSS-induced models.

Area of Science:

  • Immunology
  • Gastroenterology
  • Molecular Biology

Background:

  • LTβR activation is vital for controlling intestinal inflammation.
  • Previous studies highlighted T cell-derived LTα₁β₂ as a key activator.

Purpose of the Study:

  • To investigate the specific role of LTβR activation on macrophages and neutrophils in DSS-induced intestinal inflammation.
  • To elucidate the cellular and molecular mechanisms underlying LTβR-mediated control of inflammation.

Main Methods:

  • Generation of cell type-specific LTβR-deficient mice (LTβR((flox/flox))×LysM-Cre).
  • Adoptive transfer experiments using bone marrow-derived macrophages (BMDM) and CD4+ T cells.
  • Analysis of TRIM30α and NFκB signaling pathways, and pro-inflammatory cytokine expression.

Main Results:

  • LTβR deficiency in macrophages/neutrophils exacerbated DSS-induced intestinal inflammation.
  • LTβR activation on BMDM induced TRIM30α, a negative regulator of NFκB.
  • Ablation of LTβR signaling impaired TRIM30α induction and increased pro-inflammatory cytokines.

Conclusions:

  • LTβR signaling on macrophages, activated by CD4+ T cell-derived LTαβ, controls intestinal inflammation.
  • This control is mediated by the TRIM30α-dependent pathway, which down-regulates NFκB activation and pro-inflammatory responses.