CD95 mediated T cell apoptosis and its relevance to immune deviation

The CD95/CD95L pair plays a manifold role in regulating life and death in t he function of the immune system, Examples include CD95/CD95L acting as cyt otoxic CD8+ T cell effector molecules, or functioning on CD4+ T helper cell s to maintain peripheral tolerance or reestablishing homeostasis, Current u nderstanding of the CD95 signaling pathway reveals several potential regula tory targets, acting both receptor proximally and distally, that can termin ate or amplify the receptor's signal, The important and possibly nonredunda nt role of CD95 is highlighted both in how deficiencies in functional CD95 or its ligand manifest themselves in autoimmune syndromes, and how uncontro lled cell death results in insufficient, or inappropriate immune responses against immune challenge. This review examines CD95-mediated signal transdu ction, and the effect preferential apoptosis of T helper cell subsets has o n immune system biasing.