Analysis of the XL-EDA-ID patient's B cells. (A) Recombinant human soluble CD40L stimulation of the patient's B cells induced CD23, CD54, CD86, and CD95 up-regulation to a lesser extent. PBMCs from the patient and healthy controls were treated with (open histograms) or without (shaded histograms) recombinant human soluble CD40L (2.5 μg/mL) for 48 hours. Histograms are shown gated on CD19⁺ cells of a control, CD19⁺NEMO^low, and CD19⁺NEMO^normal cells of the patient. (B) IgD^-CD19⁺ class-switched B cells were NEMO^normal. PBMCs from the patient and healthy controls were stained with CD19, NEMO, and IgD, and CD19⁺-gated cells are shown.