Go nuts for new allergy clue
6 July 2007
Experts have uncovered a vital clue that helps explain why peanuts can send some people's immune systems into overdrive. They've found that peanut-allergic mice are missing a key immune molecule, a discovery that could bring new treatments for the killer allergy. Antenna investigates...
Around 1 in 70 children are thought to be allergic to peanuts.
Image: iStockphoto.com/Mark Dietrich
Antibodies are produced by 'B' cells, shown above.
Image: Michelle Peckham, University of Leeds/Centre for Bioscience ImageBank
Claudio Nicoletti, Institute of Food Research.
Image: Institute of Food Research
Although mice have a very similar immune system to our own, they are normally pretty resistant to allergies. Scientists only worked out how to mimic human food allergy in mice in 2000.
Claudio and his team studied mice that were prone to develop allergic reactions to food. They focused on a certain type of immune cell in the mice's gut called a 'dendritic' cell. 'Dendritic cells act like an orchestral conductor,' explains Claudio. 'They tell the other immune cells what to do.'
Jeff Temblay, Institute of Food Research.
Image: Jeff Temblay
The large cell in the top left of this image is a dendritic cell, shown interacting with other cells of the immune system.
Image: Claudio Nicoletti
In mice with a peanut allergy, IL-12 is missing at a crucial time in the immune reaction - the point at which the dendritic cells tell the other immune cells how they should react to peanuts. Without IL-12, the other immune cells respond as if peanuts are harmful.
The lining of the gut is covered with 'Peyer's patches', which have a high concentration of immune cells. Delivering IL-12 to these areas might help people with food allergies.
Image: Gordon Beakes, University of Newcastle upon Tyne/Centre for Bioscience ImageBank