An Inside Story

Leukocytes, antigens, RNA viruses—what does that even mean? How does your body know how to respond when bad things attack? It's complicated.Tod, the magnificent killer T cell, takes you into his microscopic world to experience the battles and day-to-day surveillance that go on in your bloodstream and tissues and how different kinds of cells play their specialized roles in coordinated attacks and defenses. Tod relates how he learned to be a killer T cell and what his specific role will be if his target virus should show up in the body. He explains what happens in lymph nodes and how he would be activated for battle if his sworn enemy were to appear.He observes the fog of war when bacteria invade through a wound with frantic chemical signaling between responders, as well as collateral damage among innocent bystander cells. He assists a B cell friend trying to figure out what antibodies to produce. He travels around the body, observing specialized defenses in intestinal areas and the lungs. He survives a near-death experience when the body goes into shock. Then at last, Tod's virus enemy appears, and he is activated. A battle ensues, with a bittersweet outcome.Tod's story is about the immune system and its astonishing complexity, but it is also a story about teamwork and friendship.