Figure 1

TAT-crmA inhibits both apoptosis and necroptosis in vitro. (A) Jurkat T cells were left untreated or treated with recombinant human TNFα plus CHX, zVAD and TAT-crmA as indicated. After 5 h of incubation at 37°C, cells were stained for phosphatidylserine exposure with annexin V-FITC antibody and analyzed by FACS. Presence of zVAD or TAT-crmA prevented TNFα/CHX-induced apoptotic cell death. (B) L929, HT29 and FADD^−/− Jurkat cells were left untreated or treated with TNFα plus CHX, zVAD, Nec-1 and TAT-crmA as indicated. After 5 h of incubation at 37°C, cells were stained with annexin V-FITC and analyzed by FACS. Necroptosis was induced by TNFα/CHX + zVAD and protection from necroptotic cell death was achieved by the addition of Nec-1 or TAT-crmA. (C) Western blot of cyclophilin A in the supernatant of L929 cells that were left untreated or treated for 7 h with TNFα, zVAD, Nec-1, TAT-crmA or mut.TAT-crmA, as indicated.