Platelet-Activating Factor (PAF or 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) is an important phospholipid mediator, which has diverse biological activities. PAF is synthesized and secreted by a variety of cells such as mast cells, monocytes, macrophages etc. Up-regulated PAF signaling can cause pathological inflammation and also has been found to be responsible for sepsis, shock, and traumatic injury. PAF-Acetylhydrolase (PAF-AH or 1-alkyl-2-acetylglycerophosphocholine esterase or Lipoprotein-associated Phospholipase A2 or Lp-PLA2) (EC 3.1.1.47) hydrolyzes PAF by removing acetyl group at the sn-2 position and converts PAF into biologically inactive form, lyso-PAF. PAF-AH has two forms: extracellular and intracellular that shares some