11. Normally the elastase might help break down damaged tissues so that repair could occur. 12. There appear to be two forms of neutrophil elastase , termed IIa and IIb. 13. Elastase 3B preferentially cleaves proteins after alanine residues.14. Elastase 3A preferentially cleaves proteins after alanine residues.15. However unlike other elastases, pancreatic elastase 1 is not expressed in the pancreas. 16. Acid proteinases, elastase , keratinases, and other proteinases reportedly act as virulence factors. 17. In order to minimize damage to tissues, there are few inhibitors of neutrophil elastase . 18. Reaction catalysed by pancreatic elastase 1. 19. Thus the quantification of pancreatic elastase 1 in serum allows diagnosis or exclusion of acute pancreatitis. 20. Levels of fecal elastase lower than 200 ?g / g of stool indicate an exocrine insufficiency.