Platelet Aggregation and ATP Release Induced by HIT Sera, Control Sera, and Thrombin in the Presence and Absence of ADP Receptor Inhibitor
| Agonists . | % Platelet Aggregation at 5 min (±SD; n = 3) . | ATP Release at 5 min (nmol/1010 platelets; ±SD; n = 3) . | ||
|---|---|---|---|---|
| Without ADP Rec. Inh. . | With ADP Rec. Inh. . | Without ADP Rec. Inh. . | With ADP Rec. Inh. . | |
| 2 nmol/L thrombin | 61 ± 4 | 51 ± 5 | 41 ± 6 | 32 ± 5 |
| HIT sera | ||||
| 1 | 62 ± 5 | <3 | 52 ± 4 | <1 |
| 2 | 62 ± 5 | <3 | 30 ± 4 | <1 |
| 3 | 57 ± 8 | <3 | 29 ± 4 | <1 |
| 4 | 55 ± 7 | <3 | 24 ± 4 | <1 |
| 5 | 55 ± 5 | <3 | 23 ± 5 | <1 |
| 6 | 39 ± 8 | <3 | 13 ± 2 | <1 |
| 7 | 30 ± 6 | <3 | 8 ± 3 | 3 ± 2 |
| 8 | 10 ± 4 | <3 | 2 ± 1 | <1 |
| 9, 10, 11 | <5 | <3 | <1 | <1 |
| Control sera | ||||
| 1, 2, 3 | <3 | <3 | <1 | <1 |
| Agonists . | % Platelet Aggregation at 5 min (±SD; n = 3) . | ATP Release at 5 min (nmol/1010 platelets; ±SD; n = 3) . | ||
|---|---|---|---|---|
| Without ADP Rec. Inh. . | With ADP Rec. Inh. . | Without ADP Rec. Inh. . | With ADP Rec. Inh. . | |
| 2 nmol/L thrombin | 61 ± 4 | 51 ± 5 | 41 ± 6 | 32 ± 5 |
| HIT sera | ||||
| 1 | 62 ± 5 | <3 | 52 ± 4 | <1 |
| 2 | 62 ± 5 | <3 | 30 ± 4 | <1 |
| 3 | 57 ± 8 | <3 | 29 ± 4 | <1 |
| 4 | 55 ± 7 | <3 | 24 ± 4 | <1 |
| 5 | 55 ± 5 | <3 | 23 ± 5 | <1 |
| 6 | 39 ± 8 | <3 | 13 ± 2 | <1 |
| 7 | 30 ± 6 | <3 | 8 ± 3 | 3 ± 2 |
| 8 | 10 ± 4 | <3 | 2 ± 1 | <1 |
| 9, 10, 11 | <5 | <3 | <1 | <1 |
| Control sera | ||||
| 1, 2, 3 | <3 | <3 | <1 | <1 |
Platelets were preincubated with or without 200 nmol/L ADP receptor inhibitor for 1 minute before adding the agonists. Note that HIT sera 9, 10, and 11 were also positive in SRA21 and HIPA37 tests with longer incubation times.