Triggering receptor expressed on myeloid cells-1(TREM)-1,a recently identified molecule,is involved in monocytic activation and inflammatory responses.TREM-1 is a member of natural killer cell receptor family and is expressed on neutrophils,mature monocytes and macrophages,and it can enhance the inflammatory responses mediated by Toll-like receptor-2 and -4,showing a role of inflammation promotion.Reportedly sTREM-1 was detectable in the body fluids in the presence of bacterial or fungal infection; therefore it might be used as a marker for inflammation.In addition,recombinant sTREM-1 may also be a new method for anti-inflammatory therapy.Recently,it has been found that TREM-1 not only promoted the acute inflammatory responses,but also participated in the development of chronic inflammation.This review summarizes the role of TREM-1 in the inflammation-associated dieases.