1. Arterioscler Thromb Vasc Biol
Effect of Individual Plasma Lipoprotein(a) Variations In Vivo on Its Competition With Plasminogen for Fibrin and Cell Binding
by Thierry Soulat, Stéphane Loyau, Véronique Baudouin, Lydia Maisonneuve, Marie-France Hurtaud-Roux, Nicole Schlegel, Chantal Loirat, and Eduardo Anglés-Cano
Arterioscler Thromb Vasc Biol
Volume 20(2):
February 1, 2000
Copyright © American Heart Association, Inc. All rights reserved.

2. Concentration of Lp(a) and distribution of apo(a) isoforms during the evolution of the nephrotic syndrome.
Concentration of Lp(a) and distribution of apo(a) isoforms during the evolution of the nephrotic syndrome. Top, Changes in the concentration of large (>22K, gray bars) and small (<22K, white bars) apo(a) isoforms in 4 heterozygous patients at diagnosis (left column) and at remission after 6 weeks (middle column) and 6 months (right column). Bottom, Apo(a) phenotype of plasmas shown in top panel. Apo(a) isoform size is indicated in number of kringles (29/20, 30/17, 25/17, and 26/18) by reference to a recombinant apo(a) standard.38 The black bars at the left of each immunoblot indicate the position of 3 of the recombinant apo(a) isoforms (34K, 26K, and 18K) of the reference standard.
Thierry Soulat et al. Arterioscler Thromb Vasc Biol. 2000;20:
Copyright © American Heart Association, Inc. All rights reserved.

3. Binding of Lp(a) and plasminogen to fibrin in a plasma milieu.
Binding of Lp(a) and plasminogen to fibrin in a plasma milieu. Increasing concentrations of Lp(a) added to Lp(a)- and plasminogen-depleted plasma were incubated with fibrin in the absence (▴) and in the presence of plasminogen at 1 (•) and 2 (▪) μmol/L. Bound Lp(a) was detected with a radiolabeled sheep antibody specific for apo(a). Radioactivity bound was then transformed into femtomoles of antibody bound to fibrin. In separate wells, bound plasminogen was activated with tPA and detected with a chromogenic substrate selective for plasmin; the initial velocity of the reaction was transformed into mass of plasmin(ogen) as indicated.48 The amount of anti-apo(a) antibody bound (fmol/well, main graph) and of plasminogen bound (pmol/well, inset) are represented against the input concentration of Lp(a) added to plasma. To simplify, the graph data shown represent specific binding obtained by subtracting binding in the presence of 6-aminohexanoic acid, a lysine analogue, from total binding. The Lp(a) tested contained an 18-kringle apo(a) isoform with high affinity for fibrin (Kd 12 nmol/L) as calculated from the binding isotherms according to Hervio et al.50
Thierry Soulat et al. Arterioscler Thromb Vasc Biol. 2000;20:
Copyright © American Heart Association, Inc. All rights reserved.

4. Evolution of Lp(a), apo(a), and plasminogen parameters at different stages of the nephrotic syndrome.
Evolution of Lp(a), apo(a), and plasminogen parameters at different stages of the nephrotic syndrome. A, Binding of Lp(a) to fibrin (gray bars) and THP-1 cell surfaces (white bars), performed and quantified as indicated in Figure 4. B, Plasma concentrations of plasminogen (vertically lined bars) and apo(a) (diagonally lined bars) determined by electroimmunodiffusion according to Laurell.36 The bars indicate the standard deviation of mean values (height of columns) determined at flare-up (stage 1) and at 6 weeks (stage 2) and at 6 months (stage 3) of remission.
Thierry Soulat et al. Arterioscler Thromb Vasc Biol. 2000;20:
Copyright © American Heart Association, Inc. All rights reserved.

5. Apo(a) bound to fibrin (A) and THP-1 cell surfaces (B) as a function of the apo(a) isoform/plasminogen concentration ratio.
Apo(a) bound to fibrin (A) and THP-1 cell surfaces (B) as a function of the apo(a) isoform/plasminogen concentration ratio. Plasmas were incubated with fibrin and cell surfaces, and the apo(a) bound was detected with a radiolabeled antibody directed against apo(a). The amount bound was transformed into a binding ratio by relating the value of nephrotic samples to the value of a control with undetectable levels of Lp(a). The Lp(a) binding ratio for each apo(a) isoform is plotted against the apo(a)/plasminogen molar concentration. • indicates small isoforms; ○, large isoforms. Binding ratios for each apo(a) isoform were calculated as indicated in Methods. The molar concentrations of the apo(a) isoforms were calculated by relating their molecular mass and relative proportion in plasma with the concentration of Lp(a).
Thierry Soulat et al. Arterioscler Thromb Vasc Biol. 2000;20:
Copyright © American Heart Association, Inc. All rights reserved.

6. Effect of plasminogen concentration on the amount of Lp(a) bound to fibrin (A) and THP-1 cell surfaces (B).
Effect of plasminogen concentration on the amount of Lp(a) bound to fibrin (A) and THP-1 cell surfaces (B). Experimental procedures are as indicated in Figure 3. An inverse relation was found between the amount of Lp(a) bound and plasminogen concentrations <1.3 μmol/L.
Thierry Soulat et al. Arterioscler Thromb Vasc Biol. 2000;20:
Copyright © American Heart Association, Inc. All rights reserved.