CL binding of IgG-expressing B cells. The percentage of double-positive cells (upper right gate) is expressed as the percentage of IgG-positive B cells. Binding of labeled CL vesicles and anti-IgG: (A) patient 1 and (B) healthy subject. Inhibition of labeled CL vesicles binding with nonlabeled CL vesicles (C) or with nonlabeled PC vesicles (D).