Thromb Haemost 2000; 84(06): 1082-1086
DOI: 10.1055/s-0037-1614174
Review Article
Schattauer GmbH

Immunoassays for the Quantitation of Porcine PAI-1 Antigen and Activity in Biological Fluid Samples

Henry M. J. Leng
1   From the Laboratory for Pharmaceutical Biology and Phytopharmacology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium
,
Els Brouwers
1   From the Laboratory for Pharmaceutical Biology and Phytopharmacology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium
,
Isabelle Knockaert
1   From the Laboratory for Pharmaceutical Biology and Phytopharmacology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium
,
Paul J. Declerck
1   From the Laboratory for Pharmaceutical Biology and Phytopharmacology, Faculty of Pharmaceutical Sciences, Katholieke Universiteit Leuven, Belgium
› Author Affiliations
Henry M. J. Leng was a recipient of a post-doctoral grant from the Flemish Community Government and a travel grant from the South African Foundation for Research and Development. The authors gratefully acknowledge Mrs. T. Stassen and Dr. I. De Scheerder (Dept. of Cardiology) for collection of the samples.
Further Information

Publication History

Received 18 April 1999

Accepted after revision 29 June 2000

Publication Date:
13 December 2017 (online)

Summary

Two monoclonal antibody-based enzyme-linked immunosorbent assays (ELISAs) for the quantitation of porcine plasminogen activator inhibitor-1 (PAI-1) antigen and activity in plasma were constructed and validated. The intra-assay, interassay, and interdilution coefficients of variation were 4.3, 13, and 8%, respectively, for the antigen ELISA and 5, 16, and 11% for the activity assay. Assay recoveries, in the antigen ELISA, of either latent or active recombinant porcine PAI-1 (10 and 50 ng/ml) added to plasma were 86 ± 9% and 92 ± 22%, respectively, for the latent form and 89 ± 9% and 87 ± 7% for the active form (mean ± SD, n = 3 to 4). In the immunofunctional assay, recoveries for the same concentrations of active PAI-1 were 108 ± 16% and 92 ± 21%, respectively. In male porcine plasma the level of PAI-1 antigen was 31 ± 11 ng/ ml and the activity, 34 ± 16 ng/ml (mean ± SD, n = 10). In female plasma PAI-1 antigen levels were 20 ± 5.2 ng/ml and the PAI-1 activity 42 ± 17 ng/ml (n = 13). A linear correlation was found between PAI-1 antigen and activity levels in male (r = 0.60) and female (r = 0.70) plasma. Immunodepletion resulted in a decrease of >95% of the original PAI-1 antigen or activity levels. Incubation of plasma samples at 37° C for 16 h resulted in a significant decrease (70 to 85%) of PAI-1 activity. Under these conditions (37° C, 16 h) PAI-1 antigen levels remained unchanged in males whereas the response of the female samples in the PAI-1 antigen assay increased two-fold.

In lysed platelet-rich plasma males had 990 ± 470 ng/ml antigen and 160 ± 80 ng/ml activity and females, 920 ± 500 ng/ml antigen and 150 ± 98 ng/ml activity corresponding to 2.1 ± 0.77 fg PAI-1 antigen per platelet. Only 16% of PAI-1 released from platelets was found to be active. Linear correlations between PAI-1 antigen and activity were found for both males (r = 0.61) and females (r = 0.67).

The assays are both sensitive and specific and may, therefore, aid the elucidation of the pathophysiological role of PAI-1 in swine experimental models of atherosclerosis and other thrombotic disorders.

 
  • References

  • 1 Kruithof EKO, Tran-Thang C, Ransijn A, Bachman F. Demonstration of a fast-acting inhibitor of plasminogen activators in plasma. Blood 1984; 64: 907-13.
  • 2 Vaughan DE, Declerck PJ. Fibrinolysis and its regulation. In: Thrombosis and hemorrhage. Eds. Loscalzo and Schafer, Williams & Wilkins; 1998: 155-70.
  • 3 Pannekoek H, Veerman H, Lambers H, Diergaarde P, Verweij CL, Van Zonneveld A-J, Van Mourik JA. Endothelial plasminogen activator inhibitor (PAI): a new member of the serpin gene family. EMBO J 1986; 05: 2539-44.
  • 4 Andreasen PA, Riccio A, Welinder KG, Douglas R, Sartorio R, Nielsen LS, Oppenheimer C, Blasi F, Dano K. Plasminogen activator inhibitor type-1: reactive center and amino-terminal heterogeneity determined by protein and cDNA sequencing. FEBS Lett 1986; 209: 213-8.
  • 5 Ny T, Sawdey M, Lawrence D, Millan JL, Loskutoff DJ. Cloning and sequence of a cDNA coding for the human deta-migrating endothelial-celltype plasminogen activator inhibitor. Proc Natl Acad Sci USA 1986; 83: 6776-80.
  • 6 Ginsburg D, Zeheb R, Yang AY, Rafferty UM, Andreasen PA, Nielsen L, Dano K, Lebo RV, Gelehrter TD. cDNA cloning of human plasminogen activator-inhibitor from endothelial cells. J Clin Invest 1986; 78: 1673-80.
  • 7 Hekman CM, Loskutoff DJ. Endothelial cells produce a latent inhibitor of plasminogen activators that can be activated by denaturants. J Biol Chem 1985; 260: 11581-7.
  • 8 Declerck PJ, De Mol M, Allessi M-C, Baudner S, Paques E-P, Preissner KT, Muller GBerghaus, Collen D. Purification and characterization of a plasminogen activator inhibitor 1 binding protein from human plasma. Identification as a multimeric form of S protein (vitronectin). J Biol Chem 1988; 263: 15454-61.
  • 9 Sigurdardóttir O, Wiman B. Complex formation between plasminogen activator inhibitor 1 and vitronectin in purified systems and in plasma. BBA 1990; 1035: 56-61.
  • 10 Gils A, Declerck PJ. Structure-function relationship in serpins: current concepts and controversies. Thromb Haemost 1998; 80: 531-41.
  • 11 Diéval J, Nguyen G, Gross S, Delobel J, Kruithof EKO. A lifelong bleeding disorder associated with a deficiency of plasminogen activator inhibitor type I. Blood 1991; 77: 528-32.
  • 12 Lee MH, Vosburgh E, Anderson K, McDonagh J. Deficiency of plasma plasminogen activator inhibitor 1 results in hyperfibrinolytic bleeding. Blood 1993; 81: 2357-62.
  • 13 Fay WP, Shapiro AD, Shih JL, Schleef RR, Ginsberg D. Complete deficiency of plasminogen activator inhibitor type 1 due to a frame-shift mutation. N Engl J Med 1992; 327: 1729-33.
  • 14 Schleef RR, Higgins DL, Pillemer E, Levitt LJ. Bleeding diasthesis due to decreased functional activity of type 1 plasminogen activator. J Clin Invest 1989; 83: 1747-52.
  • 15 Juhan-Vague I, Alessi MC, Declerck PJ. Pathophysiology of fibrinolysis. Baillières Clin Haematol 1995; 08: 329-43.
  • 16 Wiman B. Predictive value of fibrinolytic factors in coronary heart disease. Scand J Clin Lab Invest 1999; 59: 23-31.
  • 17 Schneidermann J, Sawdey MS, Keeton MR, Bordin GM, Bernstein EF, Dilley RB, Loskutoff DJ. Increased type 1 plasminogen activator inhibitor gene expression in atherosclerotic human arteries. Proc Natl Acad Sci USA 1992; 89: 6998-7002.
  • 18 Chomiki N, Henry M, Alessi MC, Anfosso F, Juhan-Vague I. Plasminogen activator inhibitor-1 expression in human liver and healthy or atherosclerotic vessel walls. Thromb Haemost 1994; 72: 44-53.
  • 19 Robbie LA, Booth NA, Brown PAJ, Bennett B. Inhibitors of fibrinolysis are elevated in atherosclerotic plaque. Arterioscler Thromb Vasc Biol 1996; 16: 539-45.
  • 20 Biemond BJ, Levi M, Coronel R, Janse MJ, Ten Cate JW, Pannekoek H. Thrombolysis and reocclusion in experimental jugular vein and coronary artery thrombosis. Effects of plasminogen activator inhibitor type 1-neutralizing monoclonal antibody. Circulation 1995; 91: 1175-81.
  • 21 Emeis JJ. Introduction to the Leiden Workshop on animal models in Fibrinolysis and Thrombolysis and in vitro alternatives. Fibrinolysis 1990; 04 (Suppl. 02) 1.
  • 22 Cevallos WH, Holmes WL, Myers RN, Smink RD. Swine in atherosclerosis research. Development of an experimental animal model and study of the effect of dietary fats on cholesterol metabolism. Atherosclerosis 1979; 34: 303-17.
  • 23 Fuster V, Badimon L, Badimon JJ, Ip JH, Chesebro JH. The porcine model for the understanding of thrombogenesis and atherogenesis. Mayo Clin Proc 1991; 66: 818-31.
  • 24 Lufinbühl H, Pauli B, Ratcliffe HL. Atherosclerosis in swine and swine as a model for the study of atherosclerosis. Adv Cardiol 1974; 13: 119-26.
  • 25 Lee KT, Nam SC, Florentin RA, Thomas WA. Genesis of atherosclerosis in swine fed high fat-high cholesterol diets. Med Clin North Amer 1974; 58: 281-92.
  • 26 Thorpe PE, Hunter WJ, Zhan XX, Dovgan PS, Agrawal DK. A noninjury, diet-induced swine model of atherosclerosis for cardiovascular intervention research. Angiology 1996; 47: 849-58.
  • 27 Daoud AS, Jormolych J, Augustyn JM, Fritz KE, Singh JK, Lee KT. Regression of advanced atherosclerosis in swine. Arch Pathol Lab Med 1976; 100: 372-9.
  • 28 Galfré F, Milstein C. Preparation of monoclonal antibodies: strategies and procedures. Methods Enzymol 1981; 73: 3-46.
  • 29 Bijnens AP, Knockaert I, Cousin E, Declerck PJ. Expression and characterization of recombinant porcine plasminogen activator inhibitor-1. Thromb Haemost 1997; 77: 350-6.
  • 30 Nakane PA, Kawaoi A. Peroxidase labelled antibody: a new method of conjugation. J Histochem Cytochem 1974; 22: 1084-91.
  • 31 Declerck PJ, Verstreken M, Collen D. An immunofunctional assay for active plasminogen activator inhibitor-1 (PAI-1). Fibrinolysis 1988; 02: 77-8.
  • 32 Debrock S, Declerck PJ. Characterization of common neoantigenic epitopes generated in plasminogen activator inhibitor-1 after cleavage of the reactive center loop or after complex formation with various serine proteinases. Febs Lett 1995; 376: 243-6.
  • 33 Verheijen JH, Chang GtG, Kluft C. Evidence for the occurrence of a fastacting inhibitor for tissue-type plasminogen activator in human plasma. Thromb Haemost 1984; 51: 392-5.
  • 34 Samama M, Nguyen G, Szwarcer E, Conrad J. Problems of t-PA specific inhibitor determination in human plasma. Thromb Haemost 1985; 54: 726.
  • 35 Kruithof EKO, Nicolosa G, Bachmann F. Plasminogen activator inhibitor 1: development of a radioimmunoassay and observations on its plasma concentration during venous occulsion and after platelet aggregation. Blood 1987; 70: 1645-53.
  • 36 Booth NA, Simpson AJ, Croll A, Bennett B, MacGregor IR. Plasminogen activator inhibitor (PAI-1) in plasma and platelets. Br J Haematol 1998; 70: 327-33.
  • 37 Declerck PJ, Alessi MC, Verstreken M, Kruithof EKO, Juhan-Vague I, Collen D. Measurement of plasminogen activator inhibitor 1 in biological fluids with a murine monoclonal antibody-based enzyme-linked immunosorbent assay. Blood 1988; 71: 220-5.
  • 38 Ngo TH, Verheyen S, Knockaert I, Declerck PJ. Monoclonal antibodybased immunoassays for the specific quantitation of rat PAI-1 antigen and activity in biological samples. Thromb Haemost 1998; 79: 808-12.
  • 39 Ngo TH, Declerck PJ. Immunological quantitation of rabbit plasminogen activator inhibitor-1 in biological samples. Evidence that rabbit platelets do not contain PAI-1. Thromb Haemost 1999; 82: 1510-5.
  • 40 Declerck PJ, Verstreken M, Collen D. Immunoassay of murine t-PA, u-PA and PAI-1 using monoclonal antibodies raised in gene-inactivated mice. Thromb Haemost 1995; 74: 1305-9.
  • 41 Lang IM, Marsh JJ, Moser KM, Schleef RR. Presence of active and latent type 1 plasminogen activator inhibitor associated with porcine platelets. Blood 1992; 80: 2269-74.
  • 42 Fay WP, Murphy JG, Owen WG. High concentrations of active plasminogen activator inhibitor-1 in porcine coronary artery thrombi. Arterioscler Thromb Vasc Biol 1996; 16: 1277-84.