"Hearst Magazines and Yahoo may earn commission or revenue on some items through these links." The human immune system is a remarkable evolutionary tool that is often taken for granted—until, that is, ...

Why can the human immune system often remember a vaccination for a whole lifetime? Researchers at ...

Bacteria in the human gut can directly deliver proteins into human cells, actively shaping immune responses. A consortium led by researchers at Helmholtz Munich, with participation from Ludwig ...

How does the same infection, say the flu or a cold, give some people mild symptoms and leave others suffering? Why do people develop autoimmune diseases? And will we ever be able to predict when—and ...