Ann Arbor Times

Nanoparticles delivered intravenously in mice can block allergic reactions to red meat caused by the bite of the lone star tick, new research led by the University of Michigan shows.

The condition, called alpha-gal syndrome, is on the rise in humans as climate change and other factors have led ticks to expand their habitat. Developed at U-M, the nanoparticles contain allergens that retrain the immune system to ignore the type of sugar found in beef, pork, lamb, and other mammals. Once the nanoparticles were delivered to test subjects, University of Virginia research collaborators exposed those mice to ticks to trigger an immune response to alpha-gal sugars. In 10 out of 12 mice, a reduced immune response was recorded.

A paper on the findings is published in Frontiers in Allergy.

Other nanoparticles developed at U-M have shown similar effectiveness in dealing with more common egg and peanut allergies. Research published in May showed two doses of allergen-encapsulating nanoparticles delivered intravenously prevented anaphylaxis during allergy tests in mice.

Food allergies often leave those affected with few options other than avoiding whatever products cause the reactions.

“Treating food allergies usually means desensitizing patients to the allergen so that their immune system does not react inappropriately,” said Lonnie Shea, the Steven A. Goldstein Collegiate Professor of Biomedical Engineering at U-M and co-corresponding author on the study. “Our nanoparticles, when introduced prior to or after sensitization, have been remarkably effective in reducing the immune response in multiple food allergies."

“There is potential here for a platform technology that can be used to address a variety of food-allergic responses.”

Alpha-gal syndrome is thought to be transmitted to humans via lone star tick saliva when the insect bites. It can cause hives and itching, scaly skin, swelling of the face, throat or other body parts, shortness of breath, stomach pain, diarrhea and vomiting. In some cases, it can be fatal.

In 2023, the Centers for Disease Control and Prevention estimated 450,000 U.S. residents may be living with alpha-gal syndrome—admitting that number is likely far lower than the actual figure. Historically based in the southeastern United States, lone star ticks have been increasingly found in the Midwest and Northeast as well as Canada.

“Typically when a body detects an allergen,” said Loren Erickson, associate professor of microbiology, immunology and cancer biology at UVA School of Medicine,“immune cells mistakenly identify it as a harmful substance and release antibodies that attack it."

“We found that treatment with several doses of nanoparticles reduced certain allergic reactions that were linked to changes in immune response to alpha-gal."

“While these findings highlight the first therapeutic potential of nanoparticles to treat red meat allergy," Erickson added,“we’re calling for further studies to better understand implications and long-lasting effects.”

In addition to research in mice this allergen-encapsulating nanoparticle platform has completed a phase two clinical trial for treating autoimmune condition celiac disease.

“Traditional allergen-specific immunotherapies such as oral or skin-based immunotherapy expose patient daily,” said Jessica O’Konek research assistant professor at U-M’s Mary H Weiser Food Allergy Center co-corresponding author on study.“Over time this desensitizes patients meaning immune system largely ignores allergen.” However these protocols are often months years duration patients often have allergies return if stop therapy.“

“Our goal with allergen-encapsulating nanoparticles retrain immune system tolerant small number doses ultimate goal achieving long-lived tolerance,” O’Konek said.

The research was supported by National Institutes Health Shea consultant financial interests Cour Pharmaceutical pursuing license technology.