Urokinase-type Plasminogen Actvator (uPA) is a glycosylated serine protease that is synthesized in endothelial and kidney epithelial cells.  There are two forms of uPA, the low molecular weight (LMW -31 kDa) and high molecular weight (HMW -55 kDa).   The HMW form undergoes autoproteolysis resulting in the LMW plus and 18.5 kDa amino terminal fragment (ATF).  It is this ATF that has been shown to inhibit proliferation and invasion of cancer cells by binding to uPA receptors.

Principle of Assay

This is an ELISA for the quantitative analysis of total uPA levels in biological fluids. This test operates as a sandwich ELISA where active, latent and complexed uPA enzyme complexes with PAI-1 and is quantified with the use of an HRP labeled secondary antibody.