Within the bloodstream of every living person, a form of cellular self-sacrifice unfolds continuously and without fanfare. Since 2004, scientists have understood that neutrophils—the body's most numerous immune defenders—are capable of deliberately detonating themselves, releasing sticky webs of their own DNA to ensnare and destroy pathogens they cannot otherwise contain. This mechanism, called NETosis, reframes the immune cell not merely as a soldier but as a living weapon that chooses annihilation over retreat. The same strategy that protects us from infection, however, can turn inward, impl