MLKL and multiple sclerosis: Caspase-8 activation has been reported to be the key event to determine apoptotic fate of cells (Oberst et al., 2011), and defective activation of caspase-8 is critical for RIP1/RIP3/MLKL signaling to induce oligodendrocyte necroptosis in multiple sclerosis (Ofengeim et al., 2015).