Tissue Plasminogen Activator

Abstract
TISSUE plasminogen activator (t-PA) is a naturally occurring protein that catalyzes the conversion of the inactive proenzyme plasminogen into the active serine protease plasmin. It is one of two major endogenous mammalian enzymes with this property and is found in blood and tissue from various organs. Although it exerts a similar enzymatic action, it is structurally different from the other major endogenous enzyme, urokinase. t-PA was first identified as a product of melanoma cells in 1980,1 and Rijken and Collen2 first purified the enzyme from melanoma cells in culture one year later. The isolation of the complementary DNA coding for . . .