HLA-P and alkaline phosphatase measurement: During the initiation phase of AP, especially HLAP, pancreatic enzymes, including trypsin, lipase, phospholipase A2 (PLA2), and kinin-releasing enzyme, are inappropriately activated to initiate a cascade reaction in which PLA2 breaks down cell membrane phospholipids and produces lysophosphatidic lecithin and lysophosphatidylcholine.