Abstract
1.
1. Plasminogen activator (PA) from a human pancreatic carcinoma cell line and human urinary urokinase (UK) have been purified to homogeneity. Amino acid analysis indicated they have a similar amino acid composition.
2.
2. Antibodies against both PA and UK were prepared in rabbits. Immunodiffusion experiments revealed that both enzymes were immunologically identical.
3.
3. Antibodies against PA and UK cross inhibited PAs from several other human cancer cell lines, but did not inhibit PA from cultured rat breast carcinoma R2426 cells.