Effect of MoAbs on Shear-Induced Platelet Aggregation in the Presence of vWF
| Anti-Platelet MoAb . | Disappearance of Single Platelets (%) . | |
|---|---|---|
| Anti-vWF MoAb MoAb 418 . | Anti-vWF MoAb MoAb 724 . | |
| none | 36.5 ± 2.6 | 48.5 ± 5-150 |
| 6D1 | 8.7 ± 2.1 | 8.9 ± 2.7 |
| 10E5 | 23.6 ± 3.7 | 25.1 ± 4.3 |
| Anti-Platelet MoAb . | Disappearance of Single Platelets (%) . | |
|---|---|---|
| Anti-vWF MoAb MoAb 418 . | Anti-vWF MoAb MoAb 724 . | |
| none | 36.5 ± 2.6 | 48.5 ± 5-150 |
| 6D1 | 8.7 ± 2.1 | 8.9 ± 2.7 |
| 10E5 | 23.6 ± 3.7 | 25.1 ± 4.3 |
Purified vWF was preincubated for 5 minutes with either MoAb 418 to the D′ domain of vWF, used as control antibody, or with MoAb 724 to the A1 domain. These mixtures were added to platelet suspensions that had been preincubated with MoAb to platelet receptors. A shear rate of 4,000 seconds−1 was applied for 5 minutes at 20°C. Aggregation was measured by flow cytometry and expressed as % DSP as outlined in the legend of Fig 1. Relative to MoAb 418, MoAb 724 clearly increases DSP (P < .05). This increase is reduced by either 6D1 or 10E5 to the level obtained in MoAb 418-vWF samples in the presence of the respective platelet MoAbs. Means ± SEM were calculated from three experiments performed in duplicate.
P < .05.