Reactivity of quinidine-dependent antibodies in sera from 20 patients with PECAM-1, GPIb/IX, GPIIb/IIIa, and GPIa/IIa
| Patient . | Specificity . | |||
|---|---|---|---|---|
| PECAM-1 . | GP Ib/IX . | GP IIb/IIIa . | GP Ia/IIa . | |
| 1 | (+) | 4 | 2 | — |
| 2 | — | — | — | — |
| 3 | 2 | 2 | 1 | — |
| 4 | 1 | 4 | 4 | — |
| 5 | 2 | 2 | 4 | — |
| 6 | (+) | 4 | — | — |
| 7 | 3 | 4 | 4 | — |
| 8 | 1 | 4 | 4 | — |
| 9 | — | 4 | — | — |
| 10 | 1 | 1 | 4 | — |
| 11 | 1 | 3 | (+) | — |
| 12 | 1 | 4 | — | — |
| 13 | 2 | 4 | — | — |
| 14 | 1 | 3 | 1 | — |
| 15 | 1 | 4 | 2 | — |
| 16 | — | 4 | 4 | — |
| 17 | — | 2 | — | — |
| 18 | — | — | — | — |
| 19 | (+) | 4 | — | — |
| 20 | — | — | — | — |
| aab 1 | — | — | 4 | — |
| aab 2 | — | 3 | — | — |
| aab 3 | — | 2 | 3 | — |
| allo ab | — | — | — | 4 |
| Patient . | Specificity . | |||
|---|---|---|---|---|
| PECAM-1 . | GP Ib/IX . | GP IIb/IIIa . | GP Ia/IIa . | |
| 1 | (+) | 4 | 2 | — |
| 2 | — | — | — | — |
| 3 | 2 | 2 | 1 | — |
| 4 | 1 | 4 | 4 | — |
| 5 | 2 | 2 | 4 | — |
| 6 | (+) | 4 | — | — |
| 7 | 3 | 4 | 4 | — |
| 8 | 1 | 4 | 4 | — |
| 9 | — | 4 | — | — |
| 10 | 1 | 1 | 4 | — |
| 11 | 1 | 3 | (+) | — |
| 12 | 1 | 4 | — | — |
| 13 | 2 | 4 | — | — |
| 14 | 1 | 3 | 1 | — |
| 15 | 1 | 4 | 2 | — |
| 16 | — | 4 | 4 | — |
| 17 | — | 2 | — | — |
| 18 | — | — | — | — |
| 19 | (+) | 4 | — | — |
| 20 | — | — | — | — |
| aab 1 | — | — | 4 | — |
| aab 2 | — | 3 | — | — |
| aab 3 | — | 2 | 3 | — |
| allo ab | — | — | — | 4 |
Sera were analyzed by monoclonal antibody-specific immobilization of platelet antigens (MAIPA) assay by using mabs Gi18, FMC25, Gi5, and Gi9. All tests were performed both in the presence and in the absence of 1 mg/mL quinidine. Results in the presence of the drug were evaluated as positive only if the reactivity without drug was negative. Three sera containing autoantibodies (aab) against glycoprotein IIb/IIIa and/or GPIb/IX and one serum with a GPIa/IIa-specific Bra alloantibody (alloab) were tested in the presence of quinidine to exclude drug-induced coprecipitation of platelet endothelial cell adhesion molecule-1 (PECAM-1). Tests were run in duplicates or in triplicates. Reactivity was categorized according to optical density as follows: <0.100 indicated by —; 0.100-0.199, (+); 0.200-0.399, 1; 0.400-0.799, 2; 0.800-1.599, 3; and ≥1.600, 4.