CD14 is a glycoprotein expressed on the membrane surface of monocytes/macrophages and serves as a receptor for complexes of lipopolysaccharides (LPS) and LPS binding protein (LPB), activating the toll-like receptor 4 (TLR4) specific pro-inflammatory signaling cascade on contact with infectious agents. Simultaneously, CD14 is shed from the cell membrane into the circulation forming soluble CD14 (sCD14). However, plasma protease activity generates also another sCD14 molecule called sCD14 subtype (sCD14-ST) or presepsin [Endo S et al, Ref.1].
The levels of presepsin were significantly higher in septic patients than in patients with SIRS or appearently healthy individuals [Shozushima T et al, Ref. 2].
Presepsin levels were elevated earlier than IL-6 and D-dimer along with occurrence of blood bacteria in animal model. The determination of the presepsin concentration can be used for diagnosis and prognosis of sepsis and also to monitor the course of the disease [Endo S et al, Ref. 3].