Merck, L2630-25MG, Lipopolysaccharides from Escherichia coli O111:B4

Lipopolysaccharide is a glycolipid, that is composed of carbohydrates linked to fatty acids. Lipopolysaccharides (LPSs) are characteristic components of the cell wall of Gram-negative bacteria. A typical LPS molecule has lipid A (a glucosamine-based phospholipid), a relatively short core oligosaccharide and a distal polysaccharide (O-antigen). LPSs contribute to the integrity of the outer membrane, and protect the cell against the action of bile salts and lipophilic antibiotics. They stimulate host cells via TLR2 and TLR4 (toll like receptors). This stimulation results in the generation of various proinflammatory cytokines, such as TNFα (tumor necrosis factor), IL-1 (interleukin 1) and IL-6. This product is phenol extracted from Escherichia coli serotype O111:B4. The source strain is from a private collection. This LPS serotype has been used to stimulate B-cells and induce NOS (nitric oxide synthase) in human hepatocytes.