Lymphocyte antigen 96 (LY96 or MD-2) is a glycoprotein essential for the innate response to lipopolysaccharide (LPS), binds to both LPS and the extracellular domain of Toll-like receptor 4 (TLR4) []. LY96 also associates with TLR2, enabling a response to LPS and peptidoglycan from both Gram-positive and Gram-negative bacteria []. The structure of LPS-bound LY96 has been solved, showing that the LPS binds in a deep hydrophobic cavity sandwiched by two beta sheets and that the phosphorylated glucosamine moieties are located at the entrance to the cavity [].
