LPS-binding protein (LBP) is serum factor known to regulate the endotoxin-induced cellular immune response. Sepsis is a morbid condition induced by a toxin, the introduction or accumulation of which is most commonly caused by infection or trauma. Sepsis-inducing toxins have been found associated with pathogenic bacteria, viruses, plants and venoms.
Among the well described bacterial toxins are the endotoxins or lipopolysaccharides (LPS) of the gram-negative bacteria. Upon introduction of LPS into the blood it binds to lipopolysaccharide binding protein (LBP). LBP recognizes the lipid A region of LPS and forms high affinity complexes with both rough and smooth form LPS. During the acute phase, LBP is synthesized by hepatocytes, and reaches very high concentrations in serum.