Link between CD47-induced PS exposure and cytoskeleton rearrangement.

(A) Freshly isolated B-CLL cells or the U937 cell line were cultured overnight in the presence or absence of immobilized CD47 mAbs with or without cytochalasin D (Cyto D; 20 μM). Shown is percent of dead cells (annexin-V⁺ or DiOC₆^lowcells); one representative experiment of 4 is shown. (B-D) PBMCs were isolated from 4 WAS patients and cultured in the absence (Bi) or presence (Bii) of immobilized CD47 mAb. Annexin-V/PI and DiOC₆ staining (patient no. 3) (B) and CD47 expression of PBMCs from patient no. 3 (B6H12) (C); percent viable cells (annexin-V⁻/PI⁻) in PBMCs of 4 WAS patients and 1 control donor (D).