Normal phospho-Akt levels in T-cell blasts from ALPS patients. Role of FasL in controlling Akt activation. (A) Anti–phospho-Akt (P-Akt) or anti–β-actin immunoblots were performed on extracts from day-6 T-cell blasts, obtained from healthy donors (Control) or from ALPS-Ic patient 1 or ALPS-Ia patient 2, as indicated. (B) Day-6 T-cell blasts were cultured for an additional period of 48 hours in the presence of increasing doses of IL-2, as indicated, and in the presence (+NOK-1) or absence (Control) of 1 μg/mL of the anti-FasL–blocking mAb NOK-1. The extracts used correspond to 1 × 106 cells, and the levels of P-Akt were quantified in a densitometer and normalized to the same amount of β-actin. The results obtained for the P-Akt/β-actin ratios are shown in panels A and B. In panel A, results are the mean ± SD from 4 different healthy controls and from 2 different experiments performed with the individual ALPS patients, as indicated. In panel B, results are representative of experiments performed with T-cell blasts from 4 different healthy donors. The samples shown in each immunoblot panel were run in the same gel.
