Could This Be the End of Allergies?
Allergies plague millions of people, in the form of hay fever, food allergies, or asthma. When our immune system reacts to protect us from allergens, the result can be miserable. But now relief may be on the horizon.
Researchers have recently developed a system that could possibly convince our bodies to recognize harmless allergens, such as peanuts or plant pollens, as neutral, rather than as a danger against which they must defend. Previous efforts have focused on calming the immune system, but this approach is different. These scientists are using nanoparticles as a “Trojan horse” to sneak allergens past the body’s defenses – the immune system.
The research thus far has been limited to mice subjects, and much more work is needed. But the technique is progressing to clinical trials, and it looks promising. Lead researcher Stephen Miller, of Northwestern University in Chicago, says:
Depending on what allergy you want to eliminate, you can load up the nanoparticle with ragweed pollen or a peanut protein.
The findings represent a novel, safe and effective long-term way to treat and potentially “cure” patients with life-threatening respiratory and food allergies. This may eliminate the need for life-long use of medications to treat lung allergy.
The human immune system is critical in keeping viruses and dangerous bacteria at bay. Sometimes however, for reasons that are mysterious to us, the immune system identifies harmless substances, such as animal fur or eggs, as a danger. The immune system them produces antibodies against these allergens. This results in inflammation, excess mucus, and all the miseries of allergies.
The immune system has a branch that tells the body that a substance to which it is exposed is harmless is called the “innate immune system.” However, once the body has labeled a substance as “bad,” it never comes in contact with this innate immune system again. So the researchers decided to smuggle in the information.
The scientists developed dissolvable nanoparticles made of an FDA-approved polymer. They filled these with egg protein, then injected them into mice that were allergic to eggs. Generally, the mice would develop an asthma-like reaction, but because the allergen was stored inside friendly-appearing nanoparticles, the bodies of the mice did not react. Then the nanoparticles were cleaned up by macrophages, a process that “vacuums up” any debris in the bloodstream. These macrophages are part of the innate immune system, resulting in the allergens being treated as normal. Miller explains:
The vacuum-cleaner cell presents the allergen or antigen to the immune system in a way that says, “No worries, this belongs here.”
The result? The mice were no longer allergic to eggs, and their immune systems were actually strengthened. The researchers explained that this method turns off the Th2 T cells that cause the allergy, and expands the positive, calming regulatory T cells.
In addition to its obvious possibilities in eliminating allergies, researchers hope this system may eventually overcome autoimmune diseases such as multiple sclerosis and celiac disease.