KLK2, also known as kallikerin-2 isoform1, is a secreted serine protease that is highly expressed in the human prostate gland. The enzyme is highly specific for cleavage after arginine residues. This protein is able to activate the urokinase-type plasminogen activator. It is inhibited by serpins such as protein C inhibitor, antichymotrypsin and plasminogen activator inhibitor. Recombinant human KLK2, fused to His-tag at C-terminus, was expressed in insect cell and purified by using conventional chromatography techniques.