Analysis of NEMO protein expression using intracellular staining and flow cytometry. (A) Intracellular staining of NEMO in EBV-transformed and HTLV-I-transformed cell lines. Solid lines indicate the anti-NEMO mAb, and dotted lines indicate the isotype controls. We confirmed the NEMO specificity with 2 different anti-NEMO mAbs (C73-764, BD; or clone 54, BD) and obtained identical results. (B) Intracellular staining for NEMO in PBMCs from the patient and healthy controls. The results shown were gated on lineage markers. We performed intracellular staining on PBMCs from 10 different healthy controls, all of which showed specific staining for NEMO on every lineage tested.