Binding of Quinine-Dependent Antibodies to L βIX and L αβ cells
| Patient Sera . | Antibody Binding to L βIX and L αβ Cells . | |||
|---|---|---|---|---|
| L βIX Cells . | L αβ Cells . | |||
| −QN . | +QN . | −QN . | +QN . | |
| Group 1 n = 6 | − | + | − | + |
| Group 2 n = 7 | − | + | − | − |
| Group 3 n = 2 | − | − | − | + |
| Patient Sera . | Antibody Binding to L βIX and L αβ Cells . | |||
|---|---|---|---|---|
| L βIX Cells . | L αβ Cells . | |||
| −QN . | +QN . | −QN . | +QN . | |
| Group 1 n = 6 | − | + | − | + |
| Group 2 n = 7 | − | + | − | − |
| Group 3 n = 2 | − | − | − | + |
Reactions of sera from patients with quinine-induced thrombocytopenia to L cells expressing GPIbβ and GPIX (L βIX cells) or GPIbα and GPIbβ (L αβ cells) in the presence or absence of quinine were assayed by flow cytometry and the MAIPA assay. As shown above, three distinct quinine-dependent antibody binding patterns were observed. A negative control of pooled normal AB sera did not react with either cell type in the presence of quinine (data not shown).