STAT3 protein t_1/2measurements in EBV cells from AD-HIES patients. Single representative experiments are shown for EBV cells with WT STAT3 and STAT3 F mutation R382W (A), EBV cells with STAT3 S mutations V463del or Y657S (B), and EBV cells with STAT3 S-F mutations R423Q or V637M (C). STAT3 protein t_1/2 was determined as time after CHX addition until STAT3 levels decreased to 50% of starting level, as indicated by vertical lines.