Figure 1. Dose-dependent binding of anti-PF4/P-ABS to PF4/H complexes in EIA.

PF4/H complexes were coated to a microtiter plate and binding of ABS to PF4/H complexes was measured by EIA. Mean OD values±s.d. were averaged from 5 sera for each group and 2 sera for control IgG. (a) The curve of control IgG (black stars) provides the background reaction. The specific reactions were lowest for group-1 (dark cyan circles), higher for group-2 (blue squares) and highest for group-3 (red triangles) ABS. (b) Slopes (s) of the curves obtained in (a) for concentrations up to 20 μg ml⁻¹ (at which the background for control IgG was an OD up to 0.32).