Serpin E1 (total)

Serpin E1 (Serine Protease Inhibitor E1, PAI-1, PAI, PLANH1, Plasminogen Activator Inhibitor 1) is a single-chain glycoprotein belonging to the serpin family of protease inhibitors. It is an inhibitor of both urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA). Both of these proteins convert plasminogen to plasmin. Serpin E1 exists in three different conformations including active, substrate, and inactive (or latent). Serpin E1 is secreted in the active form which can bind to select proteases through the P1-P1’ bond in the reactive-center loop (RCL). Cleavage of the P1-P1’ bond allows a covalent bond to form between Serpin E1 and the protease that it is inhibiting. Upon release of the protease, Serpin E1 changes to a more energetically stable conformation that is inactive. Active Serpin E1 is relatively unstable with a half-life of 1-2 hours in serum and spontaneously converts to the inactive conformation. In instances where the P1-P1’ bond is cleaved but movement of the RCL is obstructed, the active site remains available for binding but is not able to cleave the substrate. This results in the substrate conformation of Serpin E1. As an inhibitor of fibrinolysis, Serpin E1 has been implicated in many thrombotic disorders. It is also involved in cell adhesion, migration, and tumor invasion. Serpin E1 (total) consists of active, inactive (latent), and substrate conformations.


Serpin E1 (total) Singleplex Products

Our Serpin E1 (total) immunoassays provide fast, accurate, reproducible, and highly sensitive measurements of Serpin E1 (total). MSD’s MULTI-ARRAY technology uses simple protocols, requires minimal sample, and quantifies analyte concentration over a wide dynamic range.


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