Allergies Treatment News: Peanut Allergies: Breakthrough Could Improve Diagnoses
Peanut Allergies: Breakthrough Could Improve Diagnoses
“Caution: This product may contain nuts.” It’s an increasingly common warning on food labels of all kinds, given the recent heightened awareness of the dangers of nut allergies. Roughly three million Americans suffer from peanut allergies; yet current diagnostic methods don’t detect every case. New findings by University of Virginia scientists, however, may allow for the development of more sensitive diagnostic tools and a better understanding of nut allergies.
The study, “Structural and Immunologic Characterization of Ara h 1, a Major Peanut Allergen,” appeared in the November 11 issue of the Journal of Biological Chemistry.
Rethinking the Proteins
In the study, researchers determined that the emerging cutting-edge use of a recombinant, or artificially produced, protein in diagnostic tests may not be a suitable replacement for the natural protein Ara h 1, one of the major peanut allergens. This new insight will be critical in the effort to accurately diagnose peanut allergies and better understand their mechanisms.
“In allergy diagnostics, using a recombinant protein is thought to reveal more consistent results, as they are more homogenous than natural proteins. Individual protein molecules purified from a natural source show much more variation at a molecular level from one another,” says Wladek Minor, PhD, professor of molecular physiology and biological physics in the UVA School of Medicine and study co-leader.
“However, people are exposed to allergens from natural sources, not recombinant protein,” he continues, “and people develop antibodies to different fragments of natural allergens. If there is a significant difference between a natural source and the recombinant allergen used for allergy diagnosis, the recombinant allergen is not a good replacement in the test, because different types of allergies can be overlooked.”
In their analysis, researchers also found strong similarities in the structure of the Ara h 1 protein and those of other plant-seed proteins, which could help explain why patients with peanut allergies frequently also have allergies to tree nuts such as walnuts, almonds, and cashews.
Allergy Detection Could Save Lives
For children and adults who suffer from these serious allergies, accurate and early detection is critical. Allergic reactions to peanuts and tree nuts are the number-one cause of food-induced anaphylaxis, a life-threatening condition that develops rapidly after consumption. Armed with an accurate diagnosis, however, allergy sufferers can learn to avoid certain foods and equip themselves with a portable injection of epinephrine, the lifesaving treatment for anaphylaxis.
The team’s next steps in their research will be to determine exactly why peanut-allergic patients are often allergic to tree nuts as well, and to explain why peanut and tree-nut allergies are extremely difficult to outgrow, usually lasting a lifetime.
In addition to Minor, the international research team included Maksymilian Chruszcz, a member of Minor’s UVA research group; Soheila Maleki, from the U.S. Department of Agriculture; and Heimo Breiteneder, from the Medical University of Vienna. The multidisciplinary study included structural, bioinformatics, and immunological research on Ara h 1. Some methodology used in the project was developed as part of the NIH Protein Structure Initiative, and in particular the New York Structural Genomics Consortium.
Your guide to seasonal allergies
Ah, December! The month when the temperatures finally dip below 100 degrees and many of us prepare for the season by rushing out to stores, cash and credit cards in hand, looking for those perfect items for the tree.
Unfortunately, the season is allergy season, the items are antihistamines and decongestants, and the tree is the mountain cedar — a (sadly) drought-resistant evergreen that produces the pollen that makes many of us miserable from mid-month to late February.
The first time a particular type of pollen travels across your nasal membrane or through your lungs, your body kicks into gear and develops allergic antibodies to that pollen trigger, says Dr. Jackee Kayser, pediatric allergist at ‘Specially for Children and Dell Children’s Medical Center. When your body encounters the pollen trigger again, your immune system is waiting with the pre-formed antibodies. Histamine and other mediators head into a battle of overreaction, causing the classic allergic and even asthmatic symptoms.
Kayser says some research suggests that the immune system has to be exposed to at least two allergy seasons in order to produce an allergic reaction, which could explain why some people who have lived here for years without symptoms might suddenly find themselves affected.
Summertime’s grasses and fall’s ragweed join winter’s mountain cedar and spring’s oak pollen in testing our love for Central Texas, not to mention the molds and dust present year-round. Mountain cedar can be a bad pollen for patients, but not necessarily the worst, Kayser says, recalling an oak pollen season a few years ago when we were all driving around with the allergen covering our cars.
Prevention is the first step to battling seasonal allergies. Keep windows and doors closed. Launder pillowcases frequently, because pollen can collect in hair and be transferred to pillowcases to be breathed in throughout the night.
But once the telltale signs appear, the first step in treatment is determining whether you have a seasonal allergy or the common cold. Nasal congestion or runny nose can occur in both conditions, Kayser says, as can headaches.
One way to rule out a seasonal allergy is to remember that “cedar fever” is a misnomer. “A fever should not really accompany an allergic flare,” Kayser says. If you’re a generally allergic person and your allergy medication provides no relief, that can be another sign that allergens are not to blame.
Allergies can cause fatigue, because sufferers often don’t sleep well. But severe, flulike body aches should not result from allergies. “True muscle aches makes me concerned that there’s something else going on,” Kayser says.
It can be confusing. That’s why she recommends that patients consult an allergist. Hypersensitivity skin testing is one way to find out which environmental triggers or pollens, if any, are the cause of allergic symptoms.
Kayser usually starts with the skin prick device, which she calls “a very friendly, little device” that precludes the use of needles. A bit of the allergen is placed on the patient’s skin. Fifteen minutes later, both the bump and redness it produces are measured. Those results determine the patient’s sensitivity to that particular allergen. Once that’s known, a course of treatment can be prescribed.
In addition to prescription solutions, “nasal saline rinses and neti pots are a fantastic, nonpharmacological, therapeutic way to approach allergies,” Kayser says. In fact, she often recommends that patients use these systems before applying nasal sprays so that the sprays aren’t blocked by all of the mucus that’s being produced.
“In patients that really have significant disease, it’s usually not the sole option, but it’s a fantastic addition to helping with allergies.”
Kayser says that when patients find the typical nasal sprays and oral antihistamines ineffective (or their side effects unbearable), allergy shots help decrease sensitivity to allergens.
“It definitely is something that patients have to want to do, because it does require weekly participation for quite a while and it is a shot,” she explains. “But we know it works. If patients are just miserable and their allergy medications are not working, there’s an option out there.”
And there are other new options on the horizon.
Kayser says there is a lot of research on oral immunotherapy — popular in Europe — taking place here. Formulations containing small amounts of the problem allergen are placed under the tongue, where the substances can be quickly absorbed into the bloodstream. Although the practice has not yet been adopted as an effective therapy by the United States medical community, homeopathic remedies such as Cedar Allergy Mix can be found locally at People’s Pharmacy. It comes in drop, spray and tablet form and contains allergic agents in homeopathic dosages.