Signalling by CD95 and TNF receptors: Not only life and death

Members of the TNF family of receptors play important roles in normal physi ology and in defence. The recent rapid progress in the understanding of the mechanisms of apoptosis has been accompanied by assumptions that TNF famil y receptors such as CD95(Fas(APO-1) only have a role in regulating cell sur vival. While regulation of cell death is one important function of TNF fami ly receptors, they are capable of activating signal transduction pathways t hat have many other effects. The present review will focus on signalling of some TNF family receptors in the immune system, not only for apoptosis, bu t also for survival or activation.