The role of toll-like receptors in the immune-adrenal crosstalk

Ann N Y Acad Sci. 2006 Nov:1088:307-18. doi: 10.1196/annals.1366.027.

Abstract

Sepsis and septic shock remain major health concerns worldwide, and rapid activation of adrenal steroid release is a key event in the organism's first line of defense during this form of severe illness. Toll-like receptors (TLRs) are critical in the early immune response upon bacterial infection, and recent data from our lab demonstrate a novel link between the innate immune system and the adrenal stress response mediated by TLRs. Glucocorticoids and TLRs regulate each other in a bidirectional way. Bacterial toxins acting through TLRs directly activate adrenocortical steroid release. TLR-2 and TLR-4 are expressed in human and mice adrenals and TLR-2 deficiency is associated with an impaired glucocorticoid response. Furthermore, TLR-2 deficiency in mice is associated with marked cellular alterations in adrenocortical tissue. TLR-2-deficient mice have an impaired adrenal corticosterone release following inflammatory stress induced by bacterial cell wall compounds. This defect appears to be associated with a decrease in systemic and intraadrenal cytokine expression. In conclusion, TLRs play a crucial role in the immune-adrenal crosstalk. This close functional relationship needs to be considered in the treatment of inflammatory diseases requiring an intact adrenal stress response.

Publication types

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

MeSH terms

  • Adrenal Cortex / immunology*
  • Animals
  • Humans
  • Immune System / immunology*
  • Neuroimmunomodulation / immunology
  • Receptor Cross-Talk / immunology
  • Sepsis / immunology*
  • Toll-Like Receptors / immunology*

Substances

  • Toll-Like Receptors