Dan Murphy: Tick-et to a cure?

Lone Star tick ( CDC )

One of summer’s — and insects’ — worst curses is the red meat allergy that can develop after getting bit by the Lone Star tick. But a new treatment finally offers some hope for sufferers.

This little vignette took place way back when … actually, during the administration of Gerald Ford (who was unfairly characterized as a bumbling, slow-witted placeholder appointed after Nixon’s resignation; in an interview some years after he left office, he proved to be quite gracious, statesman-like and a sharp critic of foreign policy).

During that long, hot bicentennial summer of 1976, I had the unenviable job of hauling around a chainsaw to mow down thousands of “whips” — spindly little saplings — on a 48-acre timber unit that had been reforested a decade earlier, the idea being to eliminate the “competition” for the hybrid Douglas fir trees that were scheduled to be turned into newsprint around the turn of the new century.

Our equally spindly crew was equipped with those old-fashioned hard hats, the ones with the big wide brims that resembled World War I helmets. At the time I thought, this is stupid; why are we wearing these ungainly hunks of metal that seemed to snag every single tree branch and bush on the unit?

It didn’t take more than 10 minutes after the sun rose on day one to figure out why, as I soon began to hear, and feel, the ceaseless “dings” on that hardhat, as ticks roused by the heat of the day dropped from trees or brush and bounced off my helmet.

At the same time, I also realized why we were ordered to wear long-sleeved collared shirts, despite the 90-degree weather. In the woods. ticks are prolific and quite active in hot weather; their bites are painful and can transmit serious diseases, including Lyme disease and in the case of the Lone Star tick, a mysterious lingering allergy to red meat.

Not only have public health officials struggled to explain the causation of this syndrome, but even leading scientific researchers, who typically love to showcase their four-syllable vocabularies, can only label the red meat allergy that’s affected thousands of people as “strange.”

Unfortunately, that characterization is accurate, not only because the mechanism that causes the allergic reaction is poorly understood, but also because the syndrome doesn’t always behave like “classical” allergies. People afflicted in the aftermath of a Lone Star tick bite exhibit the hives and swelling characteristic of food allergies; however, the reaction is often delayed for hours after a meal containing meat, which complicates both diagnosis and treatment.

A big step forward

Now, a light has finally appeared to partially illuminate what has been a puzzling medical dead-end.

According to a new study published in the Journal of Immunology, scientists at the University of Virginia are close to deciphering the biological mechanisms that cause the red meat allergy, although before summarizing their findings, a trigger alert:

“This summary contains references to animal testing and may cause distress for sensitive activists who believe that computers should substitute for all medical research involving biological systems.”

The key to this study, aptly titled, “Cutaneous Exposure to Clinically Relevant Lone Star Ticks Promotes IgE Production and Hypersensitivity through CD4+ T Cell–and MyD88-Dependent Pathways in Mice,” is understanding how people become sensitized to a compound called alpha-gal, which apparently causes the immune reaction experienced by affected patients after they’ve eaten red meat.

Simply stated, the human body produces antibodies to “foreign” substances — usually proteins, although in this case, alpha-gal is a type of carbohydrate — antibodies which are then responsible for creating the symptoms associated with an allergy.

The scientists, led by Loren Erickson, an associate professor of Microbiology, Immunology and Cancer Biology at the University of Virginia, found a way to trigger the red meat allergy in specially bred laboratory mice — an essential methodology because neither mice nor humans naturally produce antibodies to alpha-gal.

Nor do computers.

“Our study used mice that are deficient in the gene that makes alpha-gal, which mirrors humans that also lack the gene that makes alpha-gal,” Erickson was quoted in an interview on Gizmodo.com.

Although Erickson, et al, admitted that there are more questions than answers at this point, they did manage to take an important step forward by identifying an antibody called IgE that is involved in causing the allergic symptoms.

The researchers created the IgE-moderated allergic reaction in the alpha-gal deficient mice, which mirrored the clinical developments observed in people after eating meat. They also were able to induce the allergy by exposing the skin of the mice to the proteins found in Lone Star tick bites, just like it occurs with people.

There’s a lot more scientific work needed before researchers can perfect an effective treatment, but it’s worth noting that none of these preliminary findings would have been achieved had scientists been restricted to running hypotheticals on some software program.

While animal rights proponents decry the “horrors” of using any living creature in medical research, they conveniently seem to overlook the pain and suffering the victims of the Lone Star tick-related allergy struggle with, often for a lifetime.

I doubt if too many activists would accept that such misery should be inflicted on one of their loved ones if it could be alleviated with the sacrifice of a few lab rats or mice.

But that’s just me. I could be wrong.

The opinions this commentary are those of Dan Murphy, an award-winning journalist and commentator.

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