SerpinB9; also known as Cytoplasmic antiproteinase 3; CAP-3; Peptidase inhibitor 9; SERPINB9 and PI-9; is a cytoplasm protein which belongs to the serpin family and Ov-serpin subfamily. Serpin-B9 ( CAP-3 / PI-9 ) is the only known human intracellular inhibitor of granzyme B (GrB); the effector molecule in immunity against cytomegalovirus (CMV) and in renal allograft rejection. Serpin-B9 and SPI-6 expression in immune-privileged cells; APCs; and CTLs protects these cells against the actions of granzyme B; and when expressed in tumor cells or virally infected hepatocytes; confers resistance to killing by CTL and NK cells. Expression of increasing levels of Serpin-B9 ( CAP-3 / PI-9 ) in target cells may progressively inhibit immune surveillance by blocking NK and CTL-induced cytotoxicity through the perforin / granzyme pathway and then through the Fas / FasL pathway. Serpin-B9 ( CAP-3 / PI-9 ) is selectively up-regulated in hepatocytes in response to infiltration of the liver by NK cells that express perforin and enzymatically active granzyme B. Upregulated expression of Serpin-B9 ( CAP-3 / PI-9 ) in NSCLC cells may serve to protect them from apoptosis induced by GrB.
Product Name:
Human SERPINB9/PI-9 Recombinant Protein (RPES1814)
<1.0 EU per µg of the protein as determined by the LAL method.
Protein Construction:
A DNA sequence encoding the human SERPINB9 (P50453) (Glu 2-Pro 376) was expressed; with a polyhistidine tag at the N-terminus.
Purity:
> 97 % as determined by reducing SDS-PAGE.
Mol Mass:
44.5 kDa
AP Mol Mass:
43 kDa
Formulation:
Lyophilized from sterile 50mM Tris; 100mM NaCl; pH 7.4
Shipping:
This product is provided as lyophilized powder which is shipped with ice packs.
Stability and Storage:
Lyophilized proteins are stable for up to 12 months when stored at -20 to -80°C. Reconstituted protein solution can be stored at 4-8°C for 2-7 days. Aliquots of reconstituted samples are stable at < -20°C for 3 months.
