Article

CpG DNA inhibits CD4+CD25+ Treg suppression through direct MyD88-dependent costimulation of effector CD4+ T cells.

Department of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
Immunology Letters (impact factor: 2.53). 03/2007; 108(2):183-8. DOI:10.1016/j.imlet.2006.12.007 pp.183-8
Source: PubMed

ABSTRACT Toll-like receptor (TLR) ligands are notable for their ability to induce APC maturation, which in turn facilitates optimal T cell mediated immune responses. Toll-like receptor ligands, such as CpG DNA, can also modulate immune responses by blocking the suppressive effects of CD4+CD25+ regulatory T cells (Tregs). Recently, we have demonstrated that CpG DNA, in addition to its actions on APCs and Tregs, can provide direct costimulatory signals to CD4+CD25- T cells. Here we show that this costimulatory effect is sufficient to abrogate suppression by Tregs. These data indicate a previously undefined role for TLR ligands in directly modulating CD4+ T cell responses.

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Keywords

abrogate suppression
 
actions
 
CD4+CD25+ regulatory T cells
 
costimulatory effect
 
CpG DNA
 
direct costimulatory signals
 
immune responses
 
induce APC maturation
 
modulate immune responses
 
modulating CD4+ T cell responses
 
Toll-like receptor
 
Toll-like receptor ligands
 
Tregs
 
turn facilitates optimal T cell