Inhibition of platelet adhesion on VEGF-stimulated endothelial cells by blocking antibodies
| Incubation with mAb or other inhibitor . | With endothelial cells . | With platelets . |
|---|---|---|
| % inhibition (SEM) . | ||
| IgG | 17 (16) | 20 (15) |
| CD31 (PECAM) | 0 (8) | 4 (6) |
| Gp-Ib | 0 (15) | 14 (15) |
| P-selectin | 0 (49) | 33 (8) |
| Tissue factor | 92 (6)† | 100 (8)† |
| Fibrin(ogen) | 0 (18) | 89 (21)* |
| Fibrin | 0 (22) | 94 (10)† |
| αvβ3 integrin (LM609) | 0 (9) | 61 (12)* |
| reopro (αIIbβ3 and αvβ3) | 0 (20) | 72 (22)* |
| Thrombin inhibitor (I1285) | ND | 100 (3)† |
| SU5416 (VEGF-R-blocker) | 86 (12)† | ND |
| Incubation with mAb or other inhibitor . | With endothelial cells . | With platelets . |
|---|---|---|
| % inhibition (SEM) . | ||
| IgG | 17 (16) | 20 (15) |
| CD31 (PECAM) | 0 (8) | 4 (6) |
| Gp-Ib | 0 (15) | 14 (15) |
| P-selectin | 0 (49) | 33 (8) |
| Tissue factor | 92 (6)† | 100 (8)† |
| Fibrin(ogen) | 0 (18) | 89 (21)* |
| Fibrin | 0 (22) | 94 (10)† |
| αvβ3 integrin (LM609) | 0 (9) | 61 (12)* |
| reopro (αIIbβ3 and αvβ3) | 0 (20) | 72 (22)* |
| Thrombin inhibitor (I1285) | ND | 100 (3)† |
| SU5416 (VEGF-R-blocker) | 86 (12)† | ND |
VEGF indicates vascular endothelial growth factor; mAb, monoclonal antibody; IgG, immunoglobulin G; PECAM, platelet-endothelial cell adhesion molecule; Gp-Ib, glycoprotein-Ib; ND, not determined; HUVEC, human umbilical vein endothelial cell.
The fluorescence-labeled platelets were allowed to adhere to the HUVECs for 30 minutes and subsequently the remaining unbound platelets were washed away. Platelet adhesion was determined by a fluorescence plate reader. The mean percentage of inhibition is calculated from 3 independent experiments (± SEM). Significant differences (
=P < .05;
= P < .01) were calculated with the Student t test. Negative inhibition values were set at zero.