CD14 is a cell surface-anchored glycoprotein that is expressed predominantly by monocytes and tissue macrophages. CD14 associates with MD-2 (LY-96) and TLR4 to form a receptor complex, which signals specifically in response to bacterial lipopolysaccharide (LPS) binding. The CD14/MD-2/TLR4 receptor complex signals via MyD88, TIRAP, and TRAF6, and ultimately activates NF-kappaB. CD14 also exists in a soluble form, designated as sCD14, which is capable of specifically binding LPS in the extracellular space. Recombinant sCD14 is a 331 amino acid glycoprotein comprising the extracellular portion of the CD14 receptor. The calculated molecular weight of Recombinant Human sCD14 is 35.6 kDa.