SERPINB1 Antibody - #DF13548

Neutrophil serine protease inhibitor that plays an essential role in the regulation of the innate immune response, inflammation and cellular homeostasis. Acts primarily to protect the cell from proteases released in the cytoplasm during stress or infection. These proteases are important in killing microbes but when released from granules, these potent enzymes also destroy host proteins and contribute to mortality. Regulates the activity of the neutrophil proteases elastase, cathepsin G, proteinase-3, chymase, chymotrypsin, and kallikrein-3. Acts also as a potent intracellular inhibitor of GZMH by directly blocking its proteolytic activity. During inflammation, limits the activity of inflammatory caspases CASP1, CASP4 and CASP5 by suppressing their caspase-recruitment domain (CARD) oligomerization and enzymatic activation. When secreted, promotes the proliferation of beta-cells via its protease inhibitory function.

Secreted. Cytoplasm. Cytoplasmic granule.

In human bone marrow, present in all CD45+ populations. Expression levels are highest in the neutrophil lineage, intermediate in monocytic, and lowest in lymphocytic lineage. Within the neutrophil lineage, expression is highest in promyelocytes.

Monomer. Interacts (via C-terminus) with CASP1; CASP4 (via CARD domain) and CASP5; these interactions regulate the activity of inflammatory caspases. Interacts with PRTN3. Interacts with GZMH.

Reactive bond 1 is specific for reaction with chymotrypsin-like protease such as cathepsin G, chymotrypsin, chymase or granzyme H, while reactive bond 2 is specific for reaction with elastase-like protease such as neutrophil elastase, proteinase-3, pancreatic elastase or PSA.

Belongs to the serpin family. Ov-serpin subfamily.