Overall, this work lays the foundation for the rational design of anti-tick vaccines that induce tick resistance-without needing to get bitten.

We found 199 tick antigens recognized by immune sera, including many proteins with histamine binding domains-key proteins secreted by ticks during feeding. Further, we developed a novel anti-tick vaccine of antigens from tick cement, and found this vaccine inhibited tick feeding.

So we built IscREAM (I. scapularis Rapid Extracellular Antigen Monitoring, and an apt name) to probe all potential extracellular or secreted tick antigens with tick-exposed or resistant serum. We were able to map the antigens recognized by humans and animal models in fine detail.

Humans and other animals can develop immunity to these tick proteins, known as acquired tick resistance. Ticks feeding on a resistant host detach early and are less likely to transmit disease. But finding which of the thousands of tick antigens leads to resistance is a challenge.

Ticks like I. scapularis feed for several days, over which time they can transmit diseases like Lyme disease and Babesiosis. To facilitate this prolonged feeding, they inject saliva proteins into the skin to numb pain, suppress the immune system, and prevent blood clotting.