Rescuing cells from apoptosis after induction in cells protected by Toxoplasma infection (MPF7P.720)

Abstract

Abstract CTLL-2, a cell line commonly used to quantify IL-2 levels, undergo apoptosis when IL-2 is not present. We previously demonstrated that infection with Toxoplasma gondii prevents this programmed cell death. We also demonstrated that Toxoplasma infection prevents apoptosis induced by beauvericin. In this study, we undertook to determine whether the protection from apoptosis provided by Toxoplasma infection is partial and only protects to the level of our assay determination, or whether it is complete and the cells could continue to grow once the apoptotic inducer is removed. Of course this is an artificial system since the parasite would normally quickly kill the cell. However, the results could be relevant when cytotoxic T lymphocytes are killing infected cells when at the same time Toxoplasma treatment drugs are employed. More importantly, the information gained from this study will help us better understand inhibition of apoptosis by Toxoplasma and of apoptotic mechanisms. Since apoptosis is involved in so many processes, understanding and potentially being able to modulate its occurrence could be valuable. Here we present the fate of cells that had apoptosis induced, were treated to prevent Toxoplasma from killing the cells, and then maintained under normal conditions.