PCSK9 (neural apoptosis-regulated convertase, NARC-1) is a 692-residue extracellular11`q protein expressed primarily in the kidneys, liver and intestines. PCSK9 has a major role in cholesterol metabolism through post-translational down regulation of LDLR, the receptor responsible for clearing LDL-C from plasma. The secreted form of PCSK9 binds to LDLR directly and results in degradation of the receptor.
PCSK9 inhibition has been shown to effectively lower plasma LDL-cholesterol. This strategy is able to enhance the LDL-cholesterol lowering ability of statins in patients with severe hypercholesterolemia who are intolerant of statins. MBL International has been leading the way in providing PCSK9 assay kits and reagents for the goal of progressing PCSK9 clinical trials.