Inhibition of eptifibatide- and tirofiban-dependent patient Abs by GPIIb- and GPIIIa-specific monoclonals
| Patient Abs . | mAbs . | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| GPIIb-specific . | GPIIIa-specific . | |||||||||
| 10E5 . | 290.5 . | 184.2 . | 312.8 . | 312.2 . | 312.6 . | 7E3 . | AP2 . | AP3 . | 330.1 . | |
| E1 | 97.0 | 96.6 | 19.9 | 17.5 | 25.9 | 27.5 | 98.6 | 48.0 | 40.0 | 49.7 |
| E2 | 94.1 | 94.5 | 14.5 | 11.2 | 82.8 | 87.4 | 99.4 | 42.3 | 46.7 | 49.9 |
| E3 | 59.8 | 50.3 | 49.5 | 47.5 | 68.3 | 74.6 | 99.5 | 75.4 | 80.9 | 75.0 |
| T1 | 26.8 | 24.6 | 6.5 | 45.2 | 41.1 | 44.6 | 93.2 | 44.9 | 40.9 | 30.0 |
| T2 | 18.7 | 0.0 | 34.2 | 3.1 | 17.6 | 25.6 | 97.5 | 95.8 | 17.8 | 4.5 |
| T3 | 16.1 | 11.1 | 5.7 | 22.9 | 17.4 | 29.3 | 93.7 | 34.4 | 44.8 | 58.2 |
| Patient Abs . | mAbs . | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| GPIIb-specific . | GPIIIa-specific . | |||||||||
| 10E5 . | 290.5 . | 184.2 . | 312.8 . | 312.2 . | 312.6 . | 7E3 . | AP2 . | AP3 . | 330.1 . | |
| E1 | 97.0 | 96.6 | 19.9 | 17.5 | 25.9 | 27.5 | 98.6 | 48.0 | 40.0 | 49.7 |
| E2 | 94.1 | 94.5 | 14.5 | 11.2 | 82.8 | 87.4 | 99.4 | 42.3 | 46.7 | 49.9 |
| E3 | 59.8 | 50.3 | 49.5 | 47.5 | 68.3 | 74.6 | 99.5 | 75.4 | 80.9 | 75.0 |
| T1 | 26.8 | 24.6 | 6.5 | 45.2 | 41.1 | 44.6 | 93.2 | 44.9 | 40.9 | 30.0 |
| T2 | 18.7 | 0.0 | 34.2 | 3.1 | 17.6 | 25.6 | 97.5 | 95.8 | 17.8 | 4.5 |
| T3 | 16.1 | 11.1 | 5.7 | 22.9 | 17.4 | 29.3 | 93.7 | 34.4 | 44.8 | 58.2 |
Platelets were treated with tirofiban or eptifibatide and were then incubated with saturating quantities of the indicated mAbs or with buffer alone. Abs from patients who experienced thrombocytopenia after treatment with eptifibatide (E1, E2, E3) or tirofiban (T1, T2, T3) were then added, and platelet-bound human IgG was measured by flow cytometry. Values shown (average of triplicate determinations) indicate the extent to which each mAb reduced the signal obtained with platelets treated with eptifibatide or tirofiban alone (expressed as percentage of inhibition).
Bold values indicate reactions inhibited by 90% or more; and underlined values, reactions inhibited by 45% or more.