The many roles of apoptotic cell death in the immune system (LL3-6) Chairperson: Shin Yonehara

Apoptosis is a genetically programmed process for killing unwanted or dangerous cells. It plays a critical role in the immune system, reflected by the observation that defects in this process can cause autoimmune disease or lymphoid malignancies. Vertebrates have two distinct but ultimately converging apoptotic pathways. One is initiated by death receptors, members of the TNF-R family with an intra-cellular 'death domain' and requires the cysteine protease, caspase-8, and its adaptor FADD. The other pathway is triggered by developmentally programmed cues, growth factor deprivation and cytotoxic stimuli and is regulated by the interplay of pro- and anti-apoptotic members of the Bcl-2 protein family. We will present data from our analysis of multiple gene-targeted and transgenic mice on the identification of the functions of Bcl-2 family members and death receptors in the control of apoptosis of cells of the immune system, with emphasis on their roles in autoimmune disease and lymphoma/leukaemia.