Proteinase inhibitor 9 (PI-9, also designated cytoplasmic antiproteinase 3, or CAP3) is a 42kD member of the ovalbumin family of serpins that is expressed in placenta, lung and cytotoxic lymphocytes. PI-9 is a potent inhibitor of granzyme B and of granzyme B-mediated apoptosis, and is also an inhibitor of capase-1 and, to a smaller extent, caspase-4 and caspase-8. PI-9 expression is also upregulated in response to inflammatory stimuli. This upregulation protects cells from apoptosis induced by endogenously expressed or released granzyme B, particulary during target cell killing.
Suitable for use in Western Blot and Immunohistochemistry. Other applications not tested.
Western Blot: 2-4ug/ml
Optimal dilutions to be determined by the researcher.
Storage and Stability:
May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.