Expression and function of Toll-like receptors in T lymphocytes

Curr Opin Immunol. 2007 Feb;19(1):39-45. doi: 10.1016/j.coi.2006.11.007. Epub 2006 Nov 28.


Toll-like receptors (TLRs) are widely expressed in the innate immune system. They recognize conserved microbial ligands such as bacterial lipopolysaccharide, lipopeptides or viral and bacterial RNA and DNA. TLRs play an essential role in innate immune responses and in the initiation of adaptive immune responses. However, certain TLRs are also expressed in T lymphocytes, and the respective ligands can directly modulate T cell function. TLR2, TLR3, TLR5 and TLR9 act as co-stimulatory receptors to enhance proliferation and/or cytokine production of T-cell receptor-stimulated T lymphocytes. In addition, TLR2, TLR5 and TLR8 modulate the suppressive activity of naturally occurring CD25(+)CD4(+) regulatory T cells. The direct responsiveness of T lymphocytes to TLR ligands offers new perspectives for the immunotherapeutic manipulation of T cell responses.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Humans
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism*
  • Toll-Like Receptors / biosynthesis*
  • Toll-Like Receptors / genetics
  • Toll-Like Receptors / physiology*


  • Toll-Like Receptors