Plasminogen fractionation

Yim, K. W., Fractionation of the human recombinant tissue plasminogen activator (rtPA) glycoforms by high-performance capillary zone electrophoresis and capillary isoelectric focusing, /. Chromatogr , 559, 401, 1991. 

Baldo-Enzi (Bl) compared the results of five different commercial immunoassays (a two-site RIA, an endpoint nephelometric assay, and three different ELlSAs) for freshly drawn serum and for plasminogen-free fractions (obtained by one-step ultracentrifugation). He observed a variable influence of plasminogen on the results of the Lp(a) determination and found no comparability between the five types of assays. This was partly due to lack of standardization. The different assays were more comparable when the plasminogen-free fraction was used. 

Bl. Baldo-Enzi, G., Baiocchi, M. R., and Crepaldi, G., Comparison of lipoprotein(a) assay methods in serum and in a plasminogen-free fraction. Clin. Chim. Acta 218, 83-95 (1993). 

Tincture of the dried seed, on agar plate at a concentration of 30 p,L/disc, was inactive on Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus. Extract of 10 g plant material in 100 mL ethanol was used b Anticoagulation activity. Serpin BSZx (an inhibitor of trypsin and chemotrypsin) inhibited thrombin, plasma kallikrein, factor Vlla/tissue factor, and factor Xa at heparin-independent association rates. Only factor Xa turned a significant fraction of BSZx over as substrate. Activated protein C and leukocyte elastase were slowly inhibited by BSZx, whereas factor Xlla, urokinase and tissue type plasminogen activator, plasmin and pancreas kallikrein, and elastase were not or only weakly affected. Trypsin from Fusarium was not inhibited, while interaction with subtilisin Carlsberg and Novo was rapid, but most BSZx was cleaved as a substrate L... 

During detailed characterization of a tryptic map of recombinant human tissue plasminogen activator (rtPA), a minor peak was resolved whose mass was not consistent with the expected set of tryptic peptides (L. Keyt and S.-L. Wu, unpublished observation). N-terminal sequence analysis of this fraction showed that it had a sequence containing residues 276-296 of rtPA with Lys-277 present as Hyl. We developed a modified amino acid analysis program capable of detecting hydroxylysine at levels down to 0.05 residues/mol to determine the distribution of Hyl in rtPA as well as in some other proteins derived from mammalian cells. 

Currently, the only treatment of patients with acute ischemic stroke is thrombolysis and restoration of blood flow [3,6,7]. Only a fraction of stroke patients benefits from this therapy [3,6,7], Therapeutic recanalization of an occluded cerebral artery is a risky option that can be applied only in the case of selected patients. The main limitation of cerebral thrombolysis is the narrow, 3-hour therapeutic window during which the thrombolytic agent has to be administered to be effective. Beyond this time limit, its effectiveness is neutralized by the high risk of cerebral hemorrhage [7], In acute stroke, only a small fraction of patients benefit from intravenous administration of recombinant tissue plasminogen activator, which is the only drug with proven effectiveness in reducing the size of infarct in humans [6],... 

Lack and Ali have reported that the tissue activator of plasminogen resides in the lysosomal fraction of cell cytoplasm and is inhibited by amino-caproic acid. This is noteworthy, since other workers " have postulated that the anti-inflammatory activity of cortisone may be attributable to its ability to prevent the release of lysosomal proteases by stabilizing the lysosomal membrane. Chloroquine may act similarly . 

Podlasek, S. J., and R. A. McPherson. 1989. Streptokinase binds to lactate dehydrogenase subunit-M which shares an epitope with plasminogen. Clinical Chemistry 35 67-73. Ratanasavanh, D., A. Tazi, M. M. Galteau, and G. Siest. 1979. Localization of gamma-glu-tamyltranferase in subcellular fractions of rat and rabbit liver Effect of phenobarbital. Biochemical Pharmacology 28 1363-1365. 

Other high molecular weight fibrinolytic substances are certain dextran fractions brinase, an enzyme derived from Aspergillus oryzae, ateroid, a naturally occuring mucopolysaccharide conplez and erythrokinase (EK) a protein isolated from red blood cells that activates human and bovine plasminogen in a manner similar to urokinase but idiich hats different physical properties ... 

This fraction contains virtually all the antibodies of plasma, as well as prothrombin, the isoagglutinins, plasminogen, and the component C, of complement. The separation of these various components is, of course, of major importance, and a systematic procedure has been developed by Oncley, Melin, Cameron, Richert and Gross (161). Briefly, it is based on the following observations ... 

Prothrombin, plasminogen, and the fibrinogen not already precipitated in Fraction I, are very insoluble at pH 5.2-5.4, even in the absence of alcohol and at moderately high ionic strengths. This fraction is denoted as III-2, or IU-2,3. 

Fraction 111-2,3—the eoglobulin fraction with minimum solubilily near pH 5.2—contains prothrombin, the midpiece (component (yj) of complement, and plasminogen, the precursor of the proteolytic enzyme of planna. 

---