The Whitehead Institute’s Hidde Ploegh is a professor of biology at MIT, and one of the world’s leading researchers in immune system behavior. He studies the various tactics that viruses employ to evade our immune responses, and the ways in which our immune system distinguishes friend from foe.

In 2002 Ploegh and his laboratory reported a new mechanism by which dendritic cells sense the presence of antigens and instruct the immune response. Using fluorescent imaging, the researchers could watch the dentritic cell carry out its task in real time.

In addition, Ploegh has helped elucidate how a certain set of glycoproteins (molecules that help the immune system recognize invaders) are put together and are delivered to the right destination to help an immune response kick in. He and his fellow researchers also discovered a new mechanism by which viruses evade the immune system.

Lately, Ploegh and his coworkers have been particularly interested in generating the chemical tools with which to probe a particular family of enzymes called proteases that are a key component of the Ubiquitin-proteasome system, one of the major mechanisms by which proteins are degraded in cells.