Vaccine offers Crohn's disease hope

A synthetic vaccine based on nanotechnology holds out the promise of halting autoimmune diseases such as Crohn's and rheumatoid arthritis, it has been reported.

Early research has shown that the molecular principle behind the approach works, at least in mice.

Scientists are excited by the findings, which hold out the prospect of new treatments for a broad range of conditions. The research could also lead to new ways of tackling the spread of cancer.

However, much more work is needed before experts can be sure the therapy is safe for humans. The research is published in the journal Nature Medicine.

The vaccine tricks the immune system into producing antibodies that target an enzyme at the heart of autoimmune diseases. Matrix metalloproteinases (MMPs) cut through structural materials such as collagen to assist cellular mobilisation and wound healing.

When some members of the enzyme family, especially the enzyme MMP9, get out of control they can promote autoimmune disease and cancer metastasis - the deadly spread of cancer around the body.

MMPs are normally held in check naturally by inhibitor molecules called TIMPs. But the biological mechanism involved is extremely precise and previous attempts to mimic it with artificial drugs have produced severe side effects.

The new research took a different tack by not targeting MMPs directly. Instead, tiny metallic vaccine molecules were created that fooled the immune system into manufacturing its own MMP-suppressing antibodies.

When the vaccine was tested on mice with a rodent version of Crohn's - a form of inflammatory bowel disease - it significantly reduced their symptoms. Untreated mice suffered severe damage to their colons while those injected with the vaccine experienced only "limited" inflammation.

Professor Irit Sagi, from the Weizmann Institute in Rehovot, Israel, said: "We are excited not only by the potential of this method to treat Crohn's, but by the potential of using this approach to explore novel treatments for many other diseases."