Surgery News

Study implicates cytokine molecule IL-17 in low back pain associated with herniated discs

November 17, 2015

"The center of the disc is immune-privileged since it has never been exposed to the immune system," says Shamji. When a disc is injured or degenerates, the body reacts against the invading inner material as it would against any virus or foreign body, and launches a response targeted at destruction. The nerve root, which is present near the protruding disc material, becomes painfully inflamed, swollen and damaged during that cascade of events.

In recent years, several anti-immune therapies, including steroids, have been injected into the space between the disc and the nerve, but with limited success, doctors say, because they don't target a specific immune response, and because low doses are used to minimize potentially serious side effects that include a higher predisposition to infection, activation of tuberculosis and a six-fold increase in lymphoma incidence.

The identification of IL-17 in the cascade of events is significant, Shamji says. "It's a product of a specific subgroup of immune cells that are involved in auto immune phenomena like rheumatoid arthritis and asthma, but not in the body's response against infection or tumor. If you target this specific lymphocyte, you may avoid compromising the body's ability to protect itself against infection or tumor."

Researchers say they're still several steps away from human studies of IL-17 blockers currently in development.

Source: Duke University Medical Center