Fig. 4.

edFAS inhibits FAS-mediated apoptosis in T cells. Jurkat T cells, stably expressing FAS constructs, were established by transfection with either the edFAS/pcDNA3 expression construct (edFAS T cells) or the wild-type FAS/pcDNA3 expression construct (wtFAS T cells). Cell viability was determined as described in the section of “Materials and Methods”. All experiments have been repeated at least three times. A). Jurkat T cells were treated with anti FAS mAb (2 μg/ml of CH-11) for 4, 8, and 18 hours. Bars (means ± S.D. of three experiments performed in triplicates) show the percentages of surviving cells after anti FAS antibody treatment. T cells expressing edFAS had significantly higher survival rates than those of the cells expressing only the wtFAS at respective time points (*, P < 0.05). B). Stable T cells expressing edFAS were treated with SuperFAS Ligand (20 ng/ml) for 4, 8, and 18 hours and expression of edFAS significantly inhibited SuperFAS Ligand-induced cell death in Jurkat T cells at respective time points (*, P < 0.05). C). Surface FAS levels detected with extracellular staining were comparable between cells tranfected with edFAS and those with wtFAS (left panel). The edFAS was undetectable in T cells transfected with wtFAS by anti edFAS mAb (1D4) (middle panel). The edFAS expression was detected in T cells transfected with edFAS (right panel).