New research out of Australia holds great promise. A study team announced in December, 2010 that they had discovered fragments of peanut protein that may be the key component to a peanut vaccine that could be given by injection.

Allergic Living’s Lisa Ferlaino spoke with Dr. Robyn O’Hehir, the team’s leader and a professor of allergy and immunology at Monash University in Australia, about the discovery and what it means.

Why the focus on immunotherapy as a treatment for peanut allergy?

“Allergen immunotherapy is the only treatment that can actually change the natural course of allergic diseases. We know from the aero-allergens such as house dust mites and grass pollens, and even from bee and wasp venom, that allergy shots make a big difference in people’s lives. That’s what we’re striving for.

We also know that peanut allergy is becoming more common worldwide, and that people find traces of peanut in unexpected foods. That’s one of the reasons avoidance isn’t really sufficient.”

Peanuts have long been viewed as too risky for immunotherapy, too likely to provoke anaphylaxis. How do you address that?

“By studying the white blood cells of patients with peanut allergy, we’ve been able to narrow down the core epitopes – the critical fragments of peanut protein that drive the allergic response in people with peanut allergy – and we’ve identified ones that are too small to cause anaphylaxis. They won’t bind to IgE [allergy antibodies], but they’re big enough to kickstart the immune system to develop tolerance.”

Are these fragments parts of peanut’s infamous Ara h 1 and Ara h 2 proteins?

“Yes. We’ve identified the critical peptides [protein fragments] in Ara h 2, the major peanut allergen. That’s the one most associated with anaphylaxis. Ara h 1 is also important, and we’re well on the way to identifying the critical peptides in it, too.”

There are a few peanut therapies in the works. Is your research unique?

“There’s a lot of research in animal models [using mice], but our research looks at human white blood cells. That’s important, because peanut allergy is not a natural condition for mice.”

Next Page: More questions on the vaccine

Recent studies of oral food desensitization suggest exciting possibilities for the 1.2 million Canadians with severe food allergies. Canadian families, particularly those families with young children living with food allergies, are understandably hopeful of medical advancements that could reduce the risk of a life threatening allergic reaction.

It is important, however, to keep the results from studies recently cited in the media in perspective. These are early days. No universal “cure” has been found. The number of study participants has been small, patients have been carefully selected, and the environments in which the studies were conducted have been very controlled.

The CSACI believes that decisions that affect public health must be evidence-based, as all good science is. There is not yet enough evidence to provide us with the information necessary to develop definitive guidelines for the public. As allergists in Canada and around the world continue to gain experience with this procedure both through research and in their own practices, the body of evidence will become greater and so too will our collective understanding of what this may mean for food allergic individuals.

In the interim, we urge families to NOT try oral desensitization for food allergies on their own. Instead, they should contact their allergist to discuss the benefits and risks of such an undertaking. Oral desensitization should only be conducted on appropriately chosen patients under the supervision and guidance of a trained and accredited allergist.

We further urge allergic individuals to continue to follow their usual safety strategies, including the individualized management plan they have developed with their allergist.

For full story Tolerating Peanut, about peanut oral immune therapy, see Summer 2009 issue.
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See Also:

• Making Peanut Allergy “Go Away“
• Canadian Peanut and Nut Allergy Statistics