Lysosphingomyelin is an endogenous bioactive sphingolipid and a constituent of lipoproteins.1,2It is produced by the removal of the acyl group from sphingomyelin by a deacylase and acts as a precursor in the biosynthesis of sphingosine-1-phosphate . D-erythroLysosphingomyelin is an agonist of the S1P receptors S1P1, S1P2, and S1P3(EC50s = 167.7, 368.1, and 482.6 nM, respectively, for the human receptors).3It is also an agonist of the orphan receptor ovarian cancer G protein-coupled receptor 1 (ORG1) that induces calcium accumulation in cells overexpressing OGR1 (EC50= ~35 nM).4Levels of D-erythrolysosphingomyelin are increased in skin isolated from patients with atopic dermatitis, as well as postmortem brain from patients with Niemann-Pick disease type A, but not type B.2,5L-threolysosphingomyelin is also an S1P1-3agonist (EC50s = 19.3, 131.8, and 313.3 nM, respectively).3This product is a mixture of D-erythroand L-threolysosphingomyelin. [Matreya, LLC. Catalog No. 1321] 1.Ito, M., Kurita, T., and Kita, K.A novel enzyme that cleaves the N-acyl linkage of ceramides in various glycosphingolipids as well as sphingomyelin to produce their lyso formsJ. Biol. Chem.270(41)24370-24374(1995) 2.Nixon, G.F., Mathieson, F.A., and Hunter, I.The multi-functional role of sphingosylphosphorylcholineProg. Lipid Res.47(1)62-75(2008) 3.Im, D.-S., Clemens, J., Macdonald, T.L., et al.Characterization of the human and mouse sphingosine 1-phosphate receptor, S1P5 (Edg-8): Structure-activity relationship of sphingosine1-phosphate receptorsBiochemistry40(46)14053-14060(2001) 4.Meyer zu Heringdorf, D., Himmel, H.M., and Jakobs, K.H.Sphingosylphosphorylcholine-biological functions and mechanisms of actionBiochim. Biophys. Acta1582(1-3)178-189(2002) 5.Rodriguez-Lafrasse, C., and Vanier, M.T.Sphingosylphosphorylcholine in Niemann-Pick disease brain: Accumulation in type A but not in type BNeurochem. Res.24(2)199-205(1999)

M199, a novel inhibitor of TLR3/9 activation, induces secretion of IL-6, IL-8 and TNFalpha in human PBMCs.