Scott Smith, MD, PhD, associate professor of Medicine in the Division of Infectious Diseases, has been awarded a five-year, $3.5 million grant from the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health, to study the human immune response to tick bites and its role in preventing tick-borne illnesses.
The research aims to shed light on the phenomenon of acquired tick resistance and its implications for diseases like alpha-gal syndrome, an acquired meat allergy associated with past exposure to certain tick bites. (According to the U.S. Centers for Disease Control and Prevention, in the five years from 2017 through 2022, some 90,000 suspected cases of alpha-gal syndrome were identified in the United States.)
The study will focus on tick-bite defenses as mounted by immunoglobulin E (IgE), an antibody involved in allergic reactions. The team will generate IgE monoclonal antibodies from individuals with alpha-gal syndrome or a history of numerous tick bites, identify the specific tick salivary proteins targeted by these antibodies, and characterize the role of IgE in immunity to tick bites using mouse models.
Smith and his team have preliminary data suggesting that repeated exposure to tick bites triggers the production of IgE antibodies targeting tick salivary proteins, potentially resulting in protection from subsequent bites.
Along with contributing to the development of strategies to prevent tick-borne illnesses, which have become an increasing public health concern in recent years, findings from the study could provide new insights into the adaptive immune system.
“This work will have implications in studies of pathogenesis and immunity of tick-borne diseases,” Smith said. “By understanding the dominant immune targets that could allow for interruption of tick feeding, we can begin to establish correlates of protection against tick bites. And there’s also reason to believe this new understanding could have implications for the transmission of infectious pathogens and disease more generally.”
The study is supported by NIH grant R01AI182247.