Methods for inducing apoptosis.

Apoptotic cells are sources of tolerogenic material during tissue homeostasis; abnormalities in apoptosis or in the clearance of apoptotic material generate a novel source of antigens against which an autoimmune response may be initiated. In our laboratory, we study the biochemistry and cell biology of systemic autoimmune disease autoantigens during different forms of cell death. Several different methods for inducing apoptosis, and for assaying the induction of this cellular process, are routinely performed. This chapter describes methods for inducing apoptosis via ultraviolet B irradiation, small molecule drug treatments, death receptor ligation, and exposure to granule components of cytotoxic lymphocytes. Assays to confirm the induction of apoptosis by quantifying changes in mitochondrial membrane potential, phosphatidylserine membrane localization, DNA content, and autoantigen cleavage are also detailed.