Electro-pulsation was carried out by 3 consecutive 10 ms rectangular pulses (240 V, electrode width 4 mm, 1 s delay). Immediately after pulse delivery, FCS was added to reach a 20% final concentration and cells were then incubated at 37uC in 2 mL RPMI medium containing 10% FCS. Under these optimized experimental conditions, 1463% (mean 6 SEM, n = 7) of the Jurkat cells transfected with the plasmid encoding EGFP robustly expressed EGFP (mean fluorescence intensity = 15886150, mean 6 SEM). HeLa cells were transiently transfected with 8 mg of plas- mids encoding EGFP, EGFP- tagged wild-type caspase-8 or EGFP-tagged wild-type caspase-10 using Lipofectamine 2000 (Invitrogen, Cergy Pontoise, France) according to manufacturers’ recommendations. HeLa cells transfected with EGFP-tagged caspase-10 were cultured in the presence of 0.8 mg/mL G418 for 45 days. 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PLoS ONE | www.plosone.org 11 October 2010 | Volume 5 | Issue 10 | e13638