Triggering Receptor Expressed on Myeloid Cells (TREM) Family and the Application of Its Antagonists

The Triggering Receptors Expressed on Myeloid cells (TREM) are a family of activating receptors with some homology with activating natural killer cell receptors. TREM-1 is an activating receptor on neutrophils and monocytes that plays an important role in the amplification of inflammation. TREM-1 blockade significantly decreases mortality from bacterial sepsis. Altered TREM-1 expression on neutrophils in response to bacterial stimuli may be an important factor in susceptibility to bacterial infection. However the natural TREM-1 ligand is unknown although Toll-like receptor agonists stimulate TREM-1 upregulation and function. TREM-2 regulates dendritic cell function by inducing CCR7 expression on peripheral dendritic cells and directing them from the periphery to the draining lymph node. These receptors may potentially be manipulated to alter the inflammatory response to severe sepsis and chronic inflammation and possible therapies and patents are explored in this review.