Fig. 4

Detection of NF-κB activation in 2D and 3D cultures by luciferase reporter assay. a Comparison of transfection efficiency between 2D and 3D culture systems. Constitutive luciferase secretion in both systems was measured at 24 hr after transfection with control vector under same experimental conditions. Data expressed as fold induction over untransfected control value. b Comparison of NF-κB activation between 2D and 3D culture systems. Transfected MRC5 lung fibroblasts were stimulated with three different doses of TNF-α for 24 h in both systems after transfection. NF-κB activation was measured as fold induction increment of luciferase reporter activity from respective untreated control. c Assessment of cell viability between 2D and 3D culture system. Cell viability was assessed by Alamar Blue assay after 24 h stimulation with different doses of TNF-α. Untreated controls were defined as 100 % and experimental data were expressed as percentage reduction compared to that of control. Data are mean ± SEM of combined results from three independent experiments and collected as triplicates samples from duplicate wells for each experiment ****p < 0.0001,**p < 0.01, ns = not significant,(n = 3)