Blood response upon DMF treatment depends on SC cell death sensitivity and NF-κB activity. (A) Time curve of the Sézary cells (SC) count of the only patient that responded on DMF therapy with a CR. Depicted are the SC values throughout the study (visit number reflects sampling every 4 weeks) in absolute number per μL. (B) Change in spontaneous CD4⁺ T-cell death rate in patient 2 (responder) and patients 3 and 4 (nonresponders) throughout the study. Spontaneous cell death was measured directly in CD4⁺ T cells freshly isolated from patients. (C) DMF sensitivity reflected by DMF-induced cell death in the CD4⁺ T cells of patients 2, 3, and 4 throughout the study. DMF-induced cell death was measured after stimulation of isolated CD4⁺ T cells of the respective patients with 30 μM DMF for 24 hours. (D) Specific luminescence in the NF-κB luciferase assay in isolated CD4⁺ T cells from patients 2, 3, and 4 spontaneously at 0 hours and 24 hours after transfection with treatment with 50 μM DMF for 24 hours. The specific NF-κB activity is normalized to a control plasmid and depicted as the ratio of both luminescence values.