Allergic to Life

Her nose is stuffy, her throat sounds scratchy, and the University of Minnesota’s Smith Hall, where Christy Haynes has an office, seems a ripe venue for dust mites, mold cultures, and other irritants you probably wouldn’t want to meet under a dark microscope. Even so, Haynes blames the redness around her eyes on an infant son who still hasn’t slept through the night—not on any airborne contaminant. “It’s really just a cold,” she says, almost apologetically. “I don’t actually have allergies.”

While she may not suffer herself, Haynes, an assistant professor of chemistry, has been singled out by the National Institutes of Health for an innovative investigation that could help bring relief to the 50 million Americans who are made miserable by itchy eyes, runny noses, and much worse. While new medications for allergy symptoms multiply every season (hay fever sufferers will now find more than 60 prescription and over-the-counter drugs made just for them), research still hasn’t fully revealed why a growing number of us have exaggerated immune responses to such generally harmless substances as pollen, pet dander, and peanuts. With the help of a $1.5 million NIH New Innovator award, Haynes and her research team hope to find some of the answers by building a cell-by-cell model of the human immune system. On credit card–sized chips built by the University’s Nanofabrication Center, investigators will isolate each cell, charting the way each reacts and communicates in turn—a painstaking process that may someday reveal the molecular science behind the sneeze or the swollen insect bite.

“We can come up with ways to treat diseases—to make symptoms better or more tolerable—but if we don’t understand fundamentally what’s happening from a biological level, we’re never going to defeat it,’’ says Haynes. “We’ll never understand why more kids are allergic or why a particular drug doesn’t work for everyone. Unless we understand how these cells talk to each other during an allergic reaction, we’re always going to be dealing with it.”

In fact, more of us are dealing with allergies than ever before. The American Academy of Allergy, Asthma & Immunology reports that more than one in two Americans now test positive to one or more allergens, making allergies the fifth most common chronic disease among adults and the third most common in kids. The surge in diagnosed allergies among children—particularly food allergies, which the Centers for Disease Control report have risen by 18 percent in the last decade—has fueled a $3.9 billion market for products aimed at consumers with food allergies and intolerance, and has sparked the creation of “peanut-free zones” in schools and daycares across the country. Whether we’re suffering from a new sensitivity to our environment or what some have termed “an epidemic of diagnosis” is not yet clear, says Malcolm Blumenthal, a professor of medicine and director of the University of Minnesota’s allergy and asthma program. But research like Haynes’ immune-system-on-a-chip could help find the answer.

“Up to now we’ve only been treating the symptoms of allergies, but she’s right where the action is,” says Blumenthal. “Allergies are an adverse immune reaction, and to understand disease you have to get down to the molecular level. Once you understand the pathways involved then you can get very rational treatment.”

“Rational” isn’t the best word to describe how the public has responded to fresh concerns about allergic reactions. Parenting blogs are full of headlines such as “Scrambled eggs almost killed my baby” and “Why won’t my doctor prescribe an Epi-pen?” that can leave the impression that we’re all at risk for a suddenly swollen windpipe. When a Massachusetts school bus was evacuated last year after a stray peanut was found rolling on the floor, one of the parents, a Harvard professor, wrote an article in the British Medical Journal titled “This allergies hysteria is just nuts,” in which he argued that sports participation is a greater risk to children than severe food allergies, yet no one would stand for football-free zones.

Even the new first family has added to the confusion about allergies in its much-debated search for a “hypoallergenic” dog—a creature that may be as mythical as the unicorn. “I suppose anything is possible,” says Blumenthal. “But the clinical wisdom is that the common allergen in all dogs is dander, and most people aren’t allergic to the hair. So the party line is if you’re allergic to one dog, you’re probably allergic to all dogs.”

While some critics have assailed food allergies as the latest form of yuppie hysteria, allergies to nuts, shellfish, and other foods are more than mere nuisance—in the United States an estimated 150 people die each year from serious allergic food reactions, while 2,000 are hospitalized. Even allergic rhinitis, the medical term for run-of-the-mill runny noses and watery eyes, takes a toll in the form of “presenteeism” (not sick enough to stay home, not well enough to get anything done), sapping $700 million every year in lost productivity, not to mention the nearly $6 billion sufferers spend on treatment.

Allergy rates have been rising steadily in the industrialized world, and theories as to why have been on the rise as well. Some scientists suggest allergies are linked to lack of sunlight and low levels of vitamin D, since those of us in northern climates have higher rates of life-threatening allergic reactions. Others say differences in food manufacturing may be a factor—Americans typically eat roasted peanuts, while Asian cultures, which have lower rates of peanut allergies, generally boil theirs. Others question the wisdom of delaying the introduction of certain allergenic foods to children, suggesting that an earlier dose might stimulate a better immune response. (One study of Jewish children found higher rates of peanut allergies among those who lived in the United Kingdom, compared to those who lived in Israel, where peanuts are introduced into the diet earlier.) Researchers in England are even infecting asthma sufferers (some 70 percent of asthmatics have allergies as well) with hookworms, a parasite that’s been missing from most of the developed world, to find out whether they once had a role in rebalancing the human immune system—and as a possible treatment path for such autoimmune diseases as diabetes and multiple sclerosis, which are also on the rise.

Yet another popular theory (often repeated by those of us whose housekeeping skills aren’t what they should be) suggests the cleanliness of our modern environment has lowered our natural resistance to allergens our ancestors may have encountered without incident—a sort of use-it-or-lose-it model of the human immune system. This so-called “hygiene hypothesis” has been used to explain why allergy rates rose after the fall of the Berlin Wall and the westernized clean-up that followed, and why larger families—whose members are, presumably, exposed to more germs than small ones—have lower rates of hay fever and eczema. Yet, as the years go by, the hygiene hypothesis hasn’t explained why asthma rates in the inner city are higher than in the newer and presumably cleaner suburbs. “I think the explanation is much more complex than hygiene,” says Blumenthal. “And it’s not genetic either. We’re talking about a change that’s taken place in the last 50 years.”

Haynes has her own hunches. “I think it has to be something in the environment. It has to be something we’re doing,” she says. “It will be interesting to see the data.”

Unfortunately, those facts aren’t likely to appear before the first buds of spring—the signal to many of us hay fever sufferers that it’s time to start breathing out of our mouths again. Still, there are some ways to mitigate the misery of allergy season.

“The first step is avoidance,” says Blumenthal. Roll up the windows, turn on the air conditioning, avoid going outdoors in the early morning and late nights when pollen counts are high, and—contrary to the hygiene hypothesis—dust and vacuum your house frequently. He acknowledges that staying indoors is a lot to ask after a long winter, and adds, “We do have some very good medicines that might be new to some patients.” For instance, the latest generation of antihistamines doesn’t have the same drowsy side effects as its predecessors on the market. New nasal steroids can help reduce inflammation, while drugs such as Singulair block leukotrienes, a substance involved in spurring allergy symptoms.

In spite of these new treatments, a 2005 survey from the Asthma and Allergy Foundation of America found that one in four allergy sufferers cycle through a host of new pills and sprays, “constantly trying different medications to find one that works.” Another 2006 survey endorsed by the American College of Allergy, Asthma, and Immunology found that more than half of all allergy sufferers experience symptoms all year long. If you’re one of them, Blumenthal recommends meeting with an allergist for a thorough history, if you haven’t already, and getting a skin or blood test to determine what’s really bothering you. For patients with persistent and severe allergies that don’t respond to other medicines, immune therapy is often the recommended treatment. In this approach, a cocktail of allergens is specially mixed for each patient and administered as a weekly shot in the arm to train the body not to react to pollen or pet dander. Monthly maintenance shots may be required for a few years, but immune therapy is successful for about 7 out of 10 patients who suffer from environmental allergies, and it has been shown to decrease the risk of asthma in children.

The needle-shy may be relieved to know that Europeans have been promoting immune therapy with sublingual allergens that dissolve under the tongue, though they have yet to win Food and Drug Administration approval. Even more treatment paths may be revealed as researchers such as Haynes learn more. Haynes adds that not being a hay fever sufferer herself doesn’t mean she lacks the motivation to help the other half of us who are miserable.

“My husband is allergic to cats,” she says. “I’m definitely motivated.”