Plasminogen

The concentration of t-PA in human blood is 2—5 ng/mL, ie, 2—5 ppb. Plasminogen activation is accelerated in the presence of a clot, but the rate is slow. The dissolution of a clot requites a week or more during normal repair of vascular damage (17). Prevention of irreversible tissue damage during a heart attack requires that a clot, formed by mpture of an atherosclerotic plaque, be dissolved in a matter of hours. This rapid thrombolysis (dissolution of the clot) must be achieved without significant tibrinogenolysis elsewhere in the patient. 

Fig. 2. Outline of possible steps in the recovery and purification sequence for recombinant tissue plasminogen activator derived from recombinant CHO...

Fig. 3. Overview of puriftcation sequence for the nonrecombinant tissue plasminogen activator (t-PA) which also contains urokinase plasminogen activator (u-PA). Serum-free culture conditional media is from normal human ceU line. The temperature for aU. steps, except for size-exclusion chromatography...

S. E. Builder, R. van Reis, N. Paoni, and J. Ogez, "Process Development and Regulatory Approval of Tissue-Type Plasminogen Activator," in... 

Sequences have been determined for plasminogen and bovine Factor XII, and they are not homologous with the other serine proteases. The amino-terminal sequence of Factor XII is homologous, however, with the active site of several naturally occurring protease inhibitors (11). 

Protein G. This vitamin K-dependent glycoproteia serine protease zymogen is produced ia the Hver. It is an anticoagulant with species specificity (19—21). Proteia C is activated to Proteia by thrombomodulin, a proteia that resides on the surface of endothefial cells, plus thrombin ia the presence of calcium. In its active form, Proteia selectively iaactivates, by proteolytic degradation. Factors V, Va, VIII, and Villa. In this reaction the efficiency of Proteia is enhanced by complex formation with free Proteia S. la additioa, Proteia activates tissue plasminogen activator, which... 

Cryoprecipitate Fresh-frozen plasma Autoplex-T VIIFC VIIFvWFAg Fibrinogen Plasminogen Factor XIII all coagulation factors, r VIIFC 11 a, Vila, IXa, Xa DH American Red Cross American Red Cross Hyland, Immuno... 

Cryoprecipitate von VIIFvWFAg VIIFC, Fibrinogen Plasminogen Factor XIII Willebrand Factor products American Red Cross... 

The secondary stmcture of the plasminogen molecule, as determined by circular dichroism spectra, is 80% random coil, 20% beta-stmcture, and 0% alpha-helix. Electron microscopy has demonstrated the tertiary stmcture of plasminogen to be a 22- to 24-nm long spiral filament with a diameter of 2.2 to 2.4 nm. 

Although the precise mechanism of plasminogen activation is unknown, three principal theories have developed based on studies of the in vitro activation of native human plasminogen. Activation of native Glu-plasminogen in the absence of any plasmin inhibitor yields Lys —plasmin plus the so-called pre-activation peptides (PAP) formed by cleavage at LySg2 S E3 Activation takes place by a two-step mechanism in... 

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