SERPINB1

Description

The SERPINB1 (serpin family B member 1) is a protein-coding gene located on chromosome 6.

SerpinB1, also known as Leukocyte elastase inhibitor (LEI), is a protein encoded by the SERPINB1 gene in humans. It belongs to the clade B serpins or ov-serpins (ovalbumin related serpins). SerpinB1 is a cytoplasmic serine protease inhibitor found in polymorphonuclear neutrophils. It specifically inhibits neutrophil elastase, PR3, and cathepsin G, all found in neutrophil granules, by a suicide inhibition mechanism. SerpinB1 reduces tissue damage caused by these proteases during inflammation and plays a role in neutrophil homeostasis in mice. Absence of SerpinB1 has been linked to a lack of microbial clearance in various infection models, such as pneumonia. Different knockout strains are used as models to investigate the role of SerpinB1 in vivo.

SerpinB1 is a crucial regulator of the innate immune response, inflammation, and cellular homeostasis. Its primary function is to protect cells from proteases released into the cytoplasm during stress or infection. These proteases are vital for killing microbes, but their uncontrolled release can damage host proteins and contribute to mortality. SerpinB1 inhibits the activity of several neutrophil proteases, including elastase, cathepsin G, proteinase-3, chymase, chymotrypsin, and kallikrein-3. It also acts as a potent intracellular inhibitor of GZMH by directly blocking its proteolytic activity. During inflammation, SerpinB1 limits the activity of inflammatory caspases CASP1, CASP4, and CASP5 by suppressing their caspase-recruitment domain (CARD) oligomerization and enzymatic activation. When secreted, SerpinB1 promotes the proliferation of beta-cells via its protease inhibitory function.

SERPINB1 is also known as EI, ELANH2, HEL-S-27, HEL57, LEI, M/NEI, MNEI, PI-2, PI2.

Associated Diseases

WES Whole Exome Sequencing