TNF

TNF (tumor necrosis factor) is the master cytokine of acute inflammation: a signaling protein that coordinates the systemic response to infection and, depending on context, kills tumor cells directly or drives the inflammation that feeds them.

Function

TNF is produced mainly by activated macrophages as a membrane-bound protein cleaved to its soluble form. It signals through two receptors: TNFR1, present on nearly all cells, which recruits the TRADD complex and can launch either NF-κB survival transcription or caspase-8-mediated apoptosis (with necroptosis as a third outcome when caspases are blocked); and TNFR2, restricted to immune cells. Systemically, TNF induces fever, the acute-phase response,