Researchers probe the secret of how ticks stick
Several creatures are able to glue themselves to rocks or solid surfaces – think mussels or spiders – but ticks are different.
We all know that getting pricked by a tick can make you sick, but what makes the tick stick?
That’s the mystery a group of 13 researchers led by Ingrid Dijkgraaf and Siddharth Deshpande at Wageningen University and Research in the Netherlands set out to solve. Their findings, published in Nature Chemistry, could lead to discoveries ranging from better tick control to new ways of dealing with wounds.
Several creatures are able to glue themselves to rocks or solid surfaces – think mussels or spiders – but ticks are different. They stick to skin. How they do it was not previously well understood.
When a tick gets onto a victim, it pierces the skin with a feeding tube and immediately starts secreting saliva containing proteins with a high concentration of glycine – the same amino acid that helps your body build proteins.
Ganar, K.A., Nandy, M., Turbina, P. et al. Phase separation and ageing of glycine-rich protein from tick adhesive. Nat. Chem. 17, 186–197 (2025). https://doi.org/10.1038/s41557-024-01686-8
These glycine-rich proteins (GRPs) quickly undergo what’s known as liquid-to-liquid phase separation, similar to the way oil and vinegar in salad dressing separates into two distinct layers. The GRPs concentrate around the edge of the pool of saliva, forming a milky-white, sticky ring that covers the host’s skin and the tick’s mouth.
The GRP-rich saliva turns into a gel-like adhesive cone within a few hours and the tick starts to feed. Over time, the cone hardens and becomes very difficult to break. Often, some of it will remain stuck to the skin, even after the tick is removed.
The researchers found that tick saliva is particularly good at liquid-to-liquid phase separation. That’s because the GRP molecules lack a fixed three-dimensional structure, allowing them to readily interact with other molecules, including themselves. That property means the proteins can more easily clump together to form the sticky glue.
The study notes that there are still many unanswered questions, including how ticks dissolve their bio-glue so they can let go after they’re finished feeding.
More research could also lead to new methods to control ticks. With a better understanding of how the adhesive is made, it should be possible to disrupt the process, making it difficult for the ticks to stay attached. And since GRPs produce an immune response, they could play a role in some future anti-tick vaccine. There is even the possibility of mimicking the tick saliva chemistry to create new adhesives that could be used to hold skin wounds together during healing.