(A) β2GPI-bh at 3×10−7 M were layered in each well of microtitre plates coated with 15 μg/well of PS. They were then incubated for 30 s (t=0), 30 min, 1 h 30 min, 3 h and 18 h. The supernatant was removed and the plates were washed three times with PBS at 4 °C. The adsorbed proteins were collected by the addition of 40 μl of SDS/PAGE sample buffer in each well, and adsorbed and non-adsorbed fractions were analysed by SDS/8% PAGE and transferred to nitrocellulose membrane. The membrane was cut into 1.5 mm wide strips and each strip was individually labelled with either the anti-β2GPI mAb 9G1 directed against the first domain of β2GPI at 5 μg/ml final concentration, in association with GAMIG-HRP or with SAV-HRP (5 μg/ml). As a control, strips were also labelled with GAMIG-HRP alone. Finally, strips were revealed by ECL® (Amersham). (B) β2GI-bh at 5×10−8 M, 3×10−7 M and 10−6 M was layered in each well of microtitre plates coated with 15 μg/well of PS. Then they were incubated for 1 h at 4 °C, 1 h 30 min at 20 °C then 1 h at 4 °C. The supernatant was removed and the plates were washed three times with PBS at 4 °C. The adsorbed proteins were collected by the addition of 40 μl of SDS/PAGE sample buffer in each well, submitted to SDS/8% PAGE, transferred to nitrocellulose membrane and revealed with the anti-β2GPI mAb 9GI at 5 μg/ml final concentration and GAMIG-HRP or with SAV-HRP (5 μg/ml).