Your Mitochondria Are Running Your Immune System’s Surveillance Network

Inside a dendritic cell, something is being decided. The cell has just swallowed a fragment of debris from a dead tumour neighbour and is now, in a sense, reading it, translating molecular scraps into instructions for the immune system’s killer T cells. Whether that message gets through with enough clarity to trigger an effective response turns out to depend not on anything obviously immunological but on a protein complex tucked into the inner membrane of the cell’s mitochondria. Complex I, as..