It can be hard to imagine there are many perks to be gleaned from tick bites, but as it happens a protein in their spit has become a key focus for certain medications. A new study published in the journal Proceedings of the National Academy of Sciences describes how a team in Australia have synthesized this protein for the first time, and how it could play a key role in preventing harmful overactive immune responses.
When ticks bite us, they’re able to keep drinking our blood without us noticing thanks to evasin proteins present in their saliva. These evasin proteins bind to chemokines in our blood that usually act as signaling proteins, triggering an immune response such as swelling and irritation. When evasin proteins bind with chemokines, it halts this immune response and they’re free to chug away without alerting the host to their presence.
While less ideal when under attack from ticks, it’s thought this immune-response blocking interaction could be harnessed for good in treating overactive immune responses such as allergic reactions to harmless irritants, for example nuts. Until now, scientists hadn’t been able to isolate these evasin proteins from the tick spit, but this new research has successfully synthesized the protein for the first time, opening up new possibilities in drug treatments.
As well as successfully synthesizing evasin proteins, PhD candidate Charlotte Frank, a member of the research team, has discovered that sulfate molecules attached to the evasin protein in tick spit are a key feature that makes them so effective at binding to chemokines. It’s hoped this discovery can be incorporated into the application of the synthetic evasin proteins by spiking them with sulfates to improve their efficacy for treating inflammatory illnesses. Such a drug could even be effective in treating Covid-19, which is now known to cause a sometimes-fatal immune response, which results in severe lung inflammation.
"We are now trying to engineer these sulfated evasin molecules to make them even more effective and more stable in blood," Frank said in a statement. "We can then start to explore how effective they could be for a range of inflammatory conditions in the clinic."