CELA3B

Function

Elastases form a subfamily of serine proteases that hydrolyze many proteins in addition to elastin. Humans have six elastase genes which encode the structurally similar proteins elastase 1, 2, 2A, 2B, 3A, and 3B. Unlike other elastases, elastase 3B has little elastolytic activity. Like most of the human elastases, elastase 3B is secreted from the pancreas as a zymogen and, like other serine proteases such as trypsin, chymotrypsin and kallikrein, it has a digestive function in the intestine. Elastase 3B preferentially cleaves proteins after alanine residues. Elastase 3B may also function in the intestinal transport and metabolism of cholesterol. Both elastase 3A and elastase 3B have been referred to as protease E and as elastase 1, and excretion of this protein in fecal material is frequently used as a measure of pancreatic function in clinical assays.

Clinical significance

Fecal elastase is a medical test that measures how well the pancreas is functioning.

The fecal elastase test measures the concentration of the elastase-3B enzyme found in fecal matter with an enzyme-linked immunosorbent assay (ELISA). Results of this test can give a good indication of exocrine pancreatic status, and the test is less invasive and expensive than the current "gold standard", secretin-cholecystokinin test. Levels of fecal elastase lower than 200 μg / g of stool indicate an exocrine insufficiency. Correlations between low levels and chronic pancreatitis and cancer have been reported.

References

References

1. (Feb 1988). "Identification of a novel class of elastase isozyme, human pancreatic elastase III, by cDNA and genomic gene cloning". J Biol Chem.
2. (Dec 1988). "Molecular cloning of complementary DNA encoding one of the human pancreatic protease E isozymes". J Biochem.
3. "Entrez Gene: ELA3B elastase 3B, pancreatic".
4. "Entrez Gene: chymotrypsin-like elastase family, member 1".
5. Molinari I.. (September 2004). "Fecal chymotrypsin and elastase-1 determination on one single stool collected at random: diagnostic value for exocrine pancreatic status". Clin Biochem.
6. Fecal Elastase 1 ELISA For Exocrine Pancreatic Insufficiency: Comparison With ERCP-Morphology And Fecal Fat Excretion [http://www.uniklinikum-giessen.de/med3/poster/publ_pdf/118.pdf] {{Webarchive. link. (2007-09-27)