Figure 4.

TNFα induces DNA-fragmentation in PCPEC. TNFα-induced apoptosis was determined by ELISA measuring the number of cellular histone-associated DNA fragments. (a) The concentration of histone-associated DNA-fragments was determined 8 hours, 24 hours, and 48 hours following apical stimulation with TNFα. PCPEC were stimulated apically with TNFα (100 ng/mL) alone or costimulated with cycloheximide (1 μg/mL). The data shown are mean ± SEM of three independent experiments, each performed in duplicate. (b) Appearance of histone-associated DNA fragments after 24 hours treatment with different doses of TNFα (1, 10, 100 ng/mL) in presence or absence of cycloheximide (1 μg/mL). A representative experiment out of three performed in duplicates is shown. OD, optical density.