Abstract
Fibrin high-affinity urokinase (UK) differed from single chain UK was purified with fibrin-Sepharose chromatography and gel filtration. The molecular weight of the purified fibrin high affinity UK (Fib-UK) was 95-100K. This Fib-UK was similar in immunological nature to UK but was different from it by molecular weight, its binding affinity for fibrin and lower specific activity (1865IU/mg). The plasminogen activator activity of Fib-UK was quenched by anti Fib-UK serum and anti UK serum. Zymogram after SDS-PAGE revealed that Fib-UK lyzed plasminogen rich fibrin plate at the molecular weight of 95-100K. Immunoelectrophoresis of Fib-UK and UK revealed that Fib-UK had an antigenicity against UK, while UK had not an antigenicity against Fib-UK.
It was concluded that Fib-UK was a protein having an activator activity, UK antigen and fibrin high affinity, and its molecular weight was 95-100K.
