Composition and phenotypical characterization of κaAPC and control beads (CB). (A) Composition of a HLA-A₂ IgG1–based κaAPC and CB. (B) FACS analysis of IgM (α-Fas mAb; left panels) and IgG1 (HLA-A₂ IgG1; right panels) immobilized on CBs and κaAPCs. ■ represents the isotype control, whereas □ indicates α-Fas mAb (clone CH11) and HLA-A₂ IgG1.