Figure 5

ESb-MP cells are resistent towards TRAIL-, CD95L- or TNF-α induced apoptosis. (A) Jurkat cells were treated with 1 μg ml⁻¹ CD95L, BL60 cells were cultured with 1 μg ml⁻¹ TRAIL and U937 cells were incubated with 1 μg ml⁻¹ TNF-α for 12 h. Apoptosis was blocked by 1–30 μg ml⁻¹ CD95-Fc, TRAIL-R2-Fc or TNF-R2-Fc. One representative experiment out of three is shown. (B) ESb-MP cells were incubated with 10 nM recombinant IFN-γ for 24 h in RPMI medium supplemented with 10% FCS followed by treatment with 1 or 10 μg ml⁻¹ TRAIL, 1 μg ml⁻¹ CD95L, 1 or 10 μg ml⁻¹ TNF-α. As a control, ESb-MP cells remained untreated (ESb-MP). (C) ESb-MP cells were cultured for 4 h alone, with Vβ6⁺ T cells (Vβ6), Vβ6⁺ T cells and IgG (10 μg ml⁻¹), with Vβ6⁺ T cells and TRAIL-R2-Fc (10 μg ml⁻¹), Vβ6⁺ T cells and CD95-Fc (10 μg ml⁻¹) or with Vβ6⁺ T cells and TNF-R2-Fc (10 μg ml⁻¹). In (B) and (C) the effector : target cell ratio was 10 : 1. The death of ESb-MP and Jurkat cells was assessed by PI staining and FACScan analysis. The mean±standard deviation from three independent experiments are shown.