AUTHOR=Bignon Alexandre , Watt Alan P. , Linterman Michelle A. 

TITLE=Escherichia coli Heat-Labile Enterotoxin B Limits T Cells Activation by Promoting Immature Dendritic Cells and Enhancing Regulatory T Cell Function

JOURNAL=Frontiers in Immunology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2017.00560

DOI=10.3389/fimmu.2017.00560

ISSN=1664-3224

ABSTRACT=<p>Treatments to limit T cell activation are essential for managing autoimmune and inflammatory disorders. The B subunit of <italic>Escherichia coli</italic> heat-labile enterotoxin (EtxB) is known to ameliorate inflammatory disease <italic>in vivo</italic> but the mechanism by which this is mediated is not well understood. Here, we show that following intranasal administration, EtxB acts on two key cellular regulators of T cell activation: regulatory T cells and dendritic cells (DCs). EtxB enhances the proliferation of lung regulatory T cells and doubles their suppressive function, likely through an increase in expression of the Treg effector molecule CTLA-4. EtxB supports the generation of interleukin-10-producing DCs that are unable to activate T cells. These data show, for the first time, that mucosal EtxB treatment limits T cells activation by acting jointly on two distinct types of immune cells.</p>