Peptidase inhibitor 3 (PI3) is an endogenous serine protease inhibitor which is expressed in the epithelium of the gastrointestinal tract. It is a 9.9kDa protein consisting of 95 amino acids. PI3 belongs to the chelonianin family of proteins and the gene encoding it is localized on chromosome 20.
Synonyms: Anti-ESI; Anti-Elafin precursor; Anti-Elastase-specific inhibitor; Anti-Peptidase inhibitor 3; Anti-Protease inhibitor WAP3; Anti-SKALP; Anti-Skin-derived antileukoproteinase; Anti-WAP four- disulfide core domain protein 14
Storage: -20C
Application: Anti-PI3 antibody produced in rabbit, a Prestige Antibody, is developed and validated by the Human Protein Atlas (HPA) project (www.proteinatlas.org). Each antibody is tested by immunohistochemistry against hundreds of normal and disease tissues. These images can be viewed on the Human Protein Atlas (HPA) site by clicking on the Image Gallery link. The antibodies are also tested using immunofluorescence and western blotting. To view these protocols and other useful information about Prestige Antibodies and the HPA, visit sigma.com/prestige.
Biochem Physiol Actions: Peptidase inhibitor 3 (PI3) has an inhibitory effect against various elastases and proteinases. It is a substrate of tissue transglutaminase 2 (TG-2), which has a cross-linking activity. In cardiovascular, respiratory and colonic inflammation, PI3 shows anti-inflammatory effects and barrier modifying properties. It is called an "alarm" antiproteinase, since it is secreted at the sites of inflammation by the same stimuli that causes initial inflammatory response. It has been shown that PI3 is overexpressed in basal-like breast cancer tumors and high-grade serous ovarian carcinoma. PI3 may also act as a marker of renal inflammation and injury.
Legal Information: Prestige Antibodies is a registered trademark of Sigma-Aldrich Co. LLC