Two is better than one against tick viruses

Ticks can transmit viruses that can cause brain infection requiring hospitalization. New work shows that one such viruses, named TBEV, rapidly develops resistance to treatment, but this can be overcome when two antibodies are combined.

Bellinzona, 25.09.2023 – Ticks can transmit a number of viruses that can cause human disease. Tick-Borne Encephalitis Virus (TBEV) is one of them: it can cause brain infections (encephalitis), which can be lethal. Despite the existence of an effective vaccine against TBEV, thousands of individuals are hospitalized every year, in Switzerland and other European Countries, because of TBEV encephalitis. Even upon recovery, neurologic problems can persist for years in affected individuals.

An international research team, which included scientists at the Institute for Research in Biomedicine (IRB, affiliated to the Università della Svizzera italiana), recently discovered antibodies that are efficacious at once against TBEV and several other tick viruses (see link).

In the new study by researchers at the IRB and the Czech Academy of Sciences (CAS), two antibodies with potential for clinical development were analyzed in more detail. Although in the presence of a single antibody, the virus was able to evolve and develop resistance to treatment, it became less pathogenic. Moreover, the combination of two antibodies was able to prevent the development of resistance altogether.

“TBEV is bit like the coronavirus” says Davide Robbiani, Head of the Laboratory of immunology and infectious disease and Director of the IRB, “it continues to mutate, finding ways to evade our defenses”. “The good news is that even if the virus escapes treatment, in doing so it becomes less harmful. And combining just two antibodies is more effective than a single antibody alone”, adds Daniel Ruzek, Head of the Laboratory of Arbovirology at CAS and co-lead on the study. These antibodies are now advancing towards the clinic for TBEV-infected patients at risk of developing encephalitis.

The work is continuing with support by a joint grant of the Swiss National Science Foundation and the Czech Science Foundation. The discovery adds to the ongoing initiative at the IRB on pandemic preparedness and emerging infectious diseases (see link).

Link to the scientific article in Cell Reports


Ixodes ticks transmitting TBEV
Photo by Jan Erhart