A recent finding from researchers at Cincinnati Children’s Hospital Medical Center could answer some important questions about severe food allergies and anaphylaxis and even lead to the development of treatments for these allergies in children. The discovery of a specific kind of cell in lab mice may explain why some people experience severe and life-threatening reactions to certain food proteins. It may also help researchers come up with a treatment that would reduce the severity or even eliminate reactions, although this possibility is far in the future.
Food Allergies and Severe Reactions
The top eight food allergens (soy, milk, eggs, wheat, fish, shellfish, tree nuts and peanuts) trigger reactions in about 4 to 6 percent of children. Some kids experience mild symptoms, while others have a severe reaction to one or more of these allergens. The severe reaction, anaphylaxis, is scary and can be life-threatening if not immediately treated.
Up until now, no one has been able to uncover a reason for this severe reaction, why some kids get it and others have only mild reactions. The latest research may have found an answer to the mystery in the form of a certain type of cell. It may be that some people have this cell, which causes the severe reaction, and others do not.
MMC9 Cells, Interleukin 9 and Anaphylaxis
The study from Cincinnati Children’s Hospital looked at lab mice with allergies to eggs. They injected the mice with egg protein and observed that, as with many food allergic children, some experienced anaphylaxis while others had milder reactions. The researchers found that the mice with severe reactions had large quantities of a type of cell called a mucosal mast cell, or MMC9. These cells produce a protein called interleukin 9 (IL-9), which is an immune system protein. Previous research has found that IL-9 is likely responsible for anaphylaxis.
The mice with milder reactions were not producing any MMC9 cells, while those with anaphylaxis produced them in significant amounts. To confirm this connection between the cells and the severe reactions, the researchers injected those mice displaying anaphylaxis and producing MMC9 cells with an antibody that destroyed the MMC9 cells. The result was that they stopped having the severe reaction. When they reintroduced the MMC9 cells, the severe reactions came back.
How This Food Allergy Research Could Help
The researchers were working with mice and have yet to find an equivalent to the MMC9 cells in humans, but they are hopeful that they can find it. They did find significant amounts of IL-9 in children with severe food allergic reactions. They now need to find the cell producing the protein in these children. Based on their findings so far, the researchers believe that children who experience anaphylaxis must have MMC9 cells.
These findings are helpful because they start to answer some questions about food allergies. The better we understand how these allergies work and why they happen to certain people and not others, the closer researchers can get to treatments or even a cure. A possible treatment would inhibit the activity of the cells producing IL-9. If some kind of treatment or medication could inhibit the process or destroy the cells, it could prevent anaphylaxis, a dream come true for many parents and children.
Unfortunately, any treatment or cure that could come as a result of this important research remains firmly in the future. For the time being, children who are at risk for anaphylaxis must avoid their food allergens and be prepared to treat the severe reaction with an epinephrine auto-injector. There is no better way to prevent or treat severe food allergies at the present, but with more research along these lines, a treatment could one day be possible.