Improving Peanut Allergy Diagnoses
December 19, 2011
CHARLOTTESVILLE, Va.—New findings by University of Virginia scientists may allow for the development of more sensitive diagnostic tools and a better understanding of nut allergies, which affects approximately 3 million Americans. The study was published in the Journal of Biological Chemistry.
According to the findings, 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," the researchers said. “However, people are exposed to allergens from natural sources, not recombinant protein, 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."
The 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 have allergies to tree nuts such as walnuts, almonds and cashews.
The team’s next research phase will be to determine exactly why peanut-allergic patients are also often allergic to tree nuts, and to explain why peanut and tree-nut allergies are extremely difficult to outgrow, usually lasting a lifetime.