A New Treatment To Prevent Asthma Is Only Skin-Deep notes the connection between skin reactions and other allergic reactions:
In the long search for the cause of asthma — a fast-growing disease that affects some nine million American children under 18 — scientists have variously blamed pollution, exposure to irritants in food and even excessive hygiene. But a new theory focuses on the kind of rashes Ryan has had as a baby. It suggests that infant eczema is the trigger of an allergic chain reaction that can lead to a childhood full of wheezing.
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The Elidel study represents another approach to asthma: trying to attack the immune system’s overreaction at its origin. Elidel inhibits a molecule called calcineurin, which is a key early activator of the allergic response. Doctors hope this will keep in check the antibody IgE, which is found at high levels in 80% of kids with eczema. IgE is seen as a master switch that turns on inflammation-producing immune cells. According to the new theory, these cells at first cluster around the skin, producing eczema in infants, and later migrate to the lymph nodes and lungs, where they cause asthma. That could explain why asthmatics tend to have high IgE levels.Evidence to support this theory came from some wheezing mice in the lab of Jonathan Spergel, an assistant professor of pediatrics at the University of Pennsylvania and the Children’s Hospital of Philadelphia. Dr. Spergel, who is a consultant to Novartis, induced eczema by smearing egg white protein — a common cause of allergies — onto the skin of young lab mice. The mice developed eczema. Next he gave these mice and healthy control animals a whiff of egg-white protein through their airways. Mice without eczema breathed normally. “But mice who had had pre-exposure to the skin would wheeze,” he says. “The mouse work really showed things went from the skin to the lungs.” Through skin irritation, he says, “we were inducing asthma.”
When scientists tried other parts of the body instead of the skin, they couldn’t induce asthma. “So the hypothesis is there’s something special about the skin,” says Thomas Hultsch, who heads dermatology research at Novartis. “The skin is the portal.”