Effect of PGE₁ on adhesion of K562-GPIb/V/IX cells to VWF.

K562-GPIb/V/IX and K562-GPIb(βSer166Gly)/V/IX cells (1 × 10⁶/mL) were perfused for 10 minutes at a shear rate of 150 s^-1 through microcapillaries coated with 1% HSA (♦) or 25 μg/mL bovine VWF (▪,■,▵). The cells were pretreated with 10 μM PGE₁ (■), 10 μM adrenaline (▵), or buffer (▪). Adherent cells were counted off-line at the indicated times and results are expressed as the mean ± SEM of 4 separate experiments. PGE₁ treatment increased adhesion of K562 cells transfected with the wild-type complex but had no effect on the adhesion of cells expressing the GPIbβ Ser166Gly mutant.