Tumor necrosis factor-induced cytotoxicity is not related to rates of mitochondrial morphological abnormalities or autophagy-changes that can be mediated by TNFR-I or TNFR-II

Tumor necrosis factor (TNF) may cause apoptosis or necrosis and induces mit ochondrial changes that have been proposed to be central to cytotoxicity. W e report similar patterns of TNF-induced mitochondrial morphological altera tions and autophagy in cell types with differing sensitivity to TNF-induced cytotoxicity. Specific ligation of TNFR-I or TNFR-II induces different rat es of apoptosis and mitochondrial morphological change, but similar rates o f autophagy. These changes do not invariably lead to cell death, and surviv al or progression to apoptosis or necrosis following TNF exposure may depen d in part on the extent of mitochondrial damage and/or the autophagic capac ity of the cell.