Maintained IL-18bp secretion by intestinal epithelial cells upon selective inhibition of IFN-γ-dependent apoptosis

Introduction: Interferon (IFN)-γ is capable of inducing apoptosis in intestinal epithelial cells (IEC), even in absence of other pro-apoptotic stimuli. At the same it alters the interleukin (IL)-18/IL-18 binding protein (bp) ratio in vitro as well as in vivo. Aim: To study presence of IL-18bp in vivo and to inhibit IFN-γ mediated apoptosis, while preserving IFN-γ dependent up-regulation of IL-18bp in vitro. Methods: Cultivated IEC lines HT-29, Caco-2 and T84 were stimulated with different concentrations of IFN-γ. Staining of phosphatidylserine, DNA laddering, cleavage of poly-ADP-ribose-polymerase (Parp) and act…