WASp expression. A, Flow cytometry characterization of WASp expression in patient and HC lymphocytes. Percentage of WASp+ cells is reported on histograms. Detection of WASp was performed after permeabilization (Cytofix/Cytoperm kit; BD Biosciences, San Jose, Calif) by a noncommercial rabbit polyclonal antibody (“EFOB,” generated against a WASp peptide), kindly provided by GSK. Gray line: negative control. B, Western blot performed on untransformed T-cell line generated in vitro from patient and his parents. Antibody for detection: polyclonal H250 (BD). C, Restoration of WASp expression in a patient's T-cell line after transduction with LV. GAPDH, Glyceraldehyde 3-phosphate dehydrogenase; HC, healthy control; LV, lentiviral vector; Pt, patient.