Figure 1: (a) Lipopolysaccharide (LPS) from the Gram-negative bacterium Escherichia coli is the most potent activator of TLR4 [54]. (b) Alpha-galactosyl ceramide from the marine sponge Agelas mauritanius is presented via CD1d and activates NKT cells [55]. (c) Partial structure of lipopeptidophosphoglycan (LPPG) from Entamoeba histolytica of the HM1 : IMSS strain, which was originally isolated from a patient with liver abscess [56, 57]. The structure of the active phosphoinositol moiety of LPPG was characterized in [58].