CD14 is a glycophosphatidylinositol-anchored protein expressed on the surfaces of monocytes and plymorphonuclear leukocytes. It cooperates with MD-2 and TLR4 to mediate the innate immune response to bacterial lipopolysaccharide (LPS). CD14 acts via MyD88, TIRAP and TRAF6, leading to NF-kappa-B activation, cytokine secretion and the inflammatory response and up-regulates cell surface molecules, including adhesion molecules.