Lipopolysaccharide-binding protein (LBP)

Lipopolysaccharide-binding protein (LBP) is a soluble, secreted, class I acute-phase glycoprotein primarily synthesized in the liver and found in blood plasma[3][7]. LBP binds bacterial lipopolysaccharide (LPS)—a key endotoxin of Gram-negative bacteria—and acts as a pattern recognition molecule in the innate immune system[1][3][7]. Upon binding LPS, LBP facilitates the transfer of LPS to CD14, TLR4, and MD-2 on monocytes and macrophages, triggering a strong pro-inflammatory cytokine response including tumor necrosis factor production[1][3]. LBP is a member of the BPI/LBP/CETP family of lipid transfer/lipopolysaccharide recognition proteins and shares structural homology with bactericidal/permeability-increasing protein (BPI)[5][4]. LBP is critical for the acute-phase response to Gram-negative infection, and its circulating levels rise rapidly during sepsis and other inflammatory states. Elevated LBP is observed in obesity, diabetes, and chronic metabolic conditions, reflecting low-grade endotoxemia[3][7]. Clinical interest has focused on LBP as a biomarker for endotoxemia and as a potential target to modulate excessive inflammatory responses to Gram-negative bacteria, though no approved drugs selectively targeting LBP currently exist[3][7]. LBP participates in the recognition and clearance of LPS from the circulation but can amplify pro-inflammatory signaling at high concentrations. Genetic variants of LBP have been associated with differential risk or clinical outcomes in sepsis, infections, metabolic syndrome, and cancer[7][4]. The structure of LBP features specialized domains for LPS binding and interaction with CD14, with disease-associated mutations mapped to functional regions[1][4][8]. No spelling or entity errors are present; this is a well-defined, therapeutically relevant immunologic protein involved in pattern recognition, acute inflammation, and host defense[3][7][1].

Other names

LBPLipopolysaccharide binding proteinLPS-binding protein

Inhibition of LBP-LPS interaction (investigational); Reduction of LBP synthesis (investigational); Disruption of LBP-mediated LPS delivery to CD14/TLR4 receptor complex (investigational)