Serpin B9 is a protein that in humans is encoded by the SERPINB9 gene. [5] [6] [7] Serpin B9 is an inhibitor of Granzyme B (GzmB). GzmB is a potent cytotoxic molecule that is secreted by cytotoxic T lymphocytes and natural killer (NK) cells to induce apoptosis in target cells during an immune response. Serpin B9, expressed in the cytosol and nucleus, thus protects from apoptosis by cytotoxic T lymphocytes and NK cells. [8]
Serpin B9 belongs to the large superfamily of serine proteinase inhibitors (serpins), which bind to and inactivate serine proteinases. These interactions are involved in many cellular processes, including coagulation, fibrinolysis, complement fixation, matrix remodeling, and apoptosis (Sprecher et al., 1995).[supplied by OMIM] [7]
This article incorporates text from the United States National Library of Medicine, which is in the public domain.