LBP (Lipopolysaccharide binding protein) is a 58-kD acute phase glycoprotein, binds to the lipid A portion of Lipopolysaccharide (LPS) with high affinity and catalyzed the CD14 and TLR4 dependent cellular activation by LPS. LBP interacted with CD14, TLR2, TLR4 und the co-receptor MD-2. LBP is involved in the acute-phase immunologic response to gram-negative bacterial infections. Gram-negative bacteria contain LPS on their outer cell wall. Together with bactericidal permeability-increasing protein (BPI), LBP binds LPS and interacts with the CD14 receptor, probably playing a role in regulating LPS-dependent monocyte responses. Earlier studies suggest that LBP is necessary for the rapid acute-phase response to LPS but not for the clearance of LPS from circulation. LBP is part of a family of structurally and functionally related proteins, including BPI, plasma cholesteryl ester transfer protein (CETP), and phospholipid transfer protein (PLTP).