TREM-1 is a 30 kD glycoprotein also known as triggering receptor expressed on myeloid cells 1, and triggering receptor expressed on monocytes 1. It is a Type I membrane protein that contains an immunoglobulin-like V-type domain. Alternatively spliced protein variant may be secreted. TREM-1 is highly expressed on peripheral blood myeloid cells (particularly mature monocytes and granulocytes); TREM-1 expression can be further upregulated by bacteria, fungi and lipopolysaccharide. TREM-1 has been shown to interact with the adaptor protein DAP12 to stimulate neutrophil and monocyte-mediated inflammatory responses through the triggering and release of pro-inflammatory cytokines and chemokines. TREM-1 is thought to amplify inflammatory responses to fungal and bacterial infections and potentiate septic shock. This antibody has been shown to be useful for flow cytometry and activation of monocytes and granulocytes.