Team discovers how to turn off peanut allergy

Scientists at at Northwestern University say they believe they’ve found a way to turn off potentially life-threatening food allergies.

When an allergic person eats a peanut, the proteins are absorbed through the intestine and can activate a full-body immune response. This includes constriction of the airways, low blood pressure and shock, and can be fatal.

But, it seems, the answer is to convince the immune system that the nut proteins aren’t a threat to the body.

The technique involved attaching peanut proteins onto white blood cells, or leukocytes, in a mouse model that mimics a life-threatening peanut allergy.

After two treatments, the mice were fed a peanut extract, but failed to show the life-threatening allergic reaction because their immune system now recognized the protein as safe.

While this method’s previously been used to target autoimmune diseases, it’s the first time it’s been used in allergic autoimmune diseases.

A welcome side-effect of the treatment is that it creates a more normal, balanced immune system by increasing the number of regulatory T cells, immune cells important for recognizing the peanut proteins as normal.

“T cells come in different ‘flavors’. This method turns off the dangerous Th2 T cell that causes the allergy and expands the good, calming regulatory T cells,” says assistant professor of medicine Paul Bryce.

“We are supposed to be able to eat peanuts. We’ve restored this tolerance to the immune system.”

Each year in the US there are between 15,000 and 30,000 episodes of food-induced anaphylaxis – a life-threatening allergic reaction – with up to 200 related deaths.