NF-kB p65, IkB-alfa and phospho-IkB-alfa in LCLs and fibroblats and relative densitometry. A) Western blot of NF-kB p65 nuclear levels and B-C) IkB-alfa and phospho-IkB-alfa cytosolic levels LCLs and relative densitometry. p65, IkB-alfa and phospho-IkB-alfa protein levels in fetal fibroblasts from one DS subject and one control are shown as well. As internal controls, tubulin and H1 histone were used for cytosolic and nuclear marker proteins, respectively. D) NF-kB Luciferase assay in lymphoblasts. Histograms show the average of the activity, expressed as relative light units (RLU), of DS subjects (n = 3) versus controls (n = 3) normalized on the average of the b-galactosidase activity. Experiments were performed in triplicate and repeated twice. * p < 0.05.