 Toll-like receptors (TLRs) can also signal to the necrosome, leading to necroptosis.TLRs are a class of receptors that function in the innate immune system to recognize conserved components of pathogens, such as flagellin.In apoptosis, extrinsic signaling via cell surface receptors or intrinsic signaling by release of cytochrome c from mitochondria leads to caspase activation.