The researchers carried out their investigations both on skin samples from test persons and on human skin models on which the bite of the common wood tick (Ixodes ricinus, colloquially: tick) was imitated. In both cases, the team noted rapidly emerging patterns of immune modulation.
Immune cell function disrupted
For example, it was found that the function of the immune cells, especially the T cells that are important for immunological memory, was disrupted by contact with tick saliva. The scientists made similar observations in the early stages of model infections caused by Borrelia burgdorferi, the most common pathogen of Lyme disease. It turned out that the pre-incubation of Lyme disease-transmitting bacteria (spirochetes) with tick salivary gland extracts hinders the accumulation of immune cells in the skin and increases the burden of pathogens.
“Overall, we show that sucking the tick causes profound changes in the skin’s immune system, which inhibit the immune response. This means that dangerous pathogens, which are introduced into the skin together with tick saliva, multiply more easily and thus lead to an infection can,” said Johanna Strobl, first author of the study, summarizing the central research results. The study was carried out under the direction of Georg Stary (among others, MedUni Vienna’s Department of Dermatology) in collaboration with Hannes Stockinger’s research group (Center for Pathophysiology, Infectious Diseases and Immunology at MedUni Vienna).
Location in Austria
Austria is one of the countries in the world with the highest spread of ticks. Almost every second common wood goat is infected with pathogens, Lyme disease and tick-borne encephalitis (TBE) are the most common diseases transmitted by ticks. The arachnids become active from a temperature of seven degrees. Due to the temperature changes in the context of the climate crisis, ticks are now also a danger in higher-lying regions of Austria and well into late autumn.