Critical milestone reached in radical new antiviral treatment approach

The VIROFIGHT team has succeeded with a first proof-of-concept for its virus engulfing and neutralizing nano-shells

Instead of targeting virus-specific proteins or enzymes by small molecules as done by current antivirals, researchers of the EU-funded VIROFIGHT project develop nano-shells that engulf and neutralize entire viruses. This novel approach may one day help fight multiple viruses such as Sars-CoV-2, HIV, influenza and hepatitis B with one and the same platform. A year after the project has started, the team led by project coordinator Hendrik Dietz of the Technical University of Munich (TUM) has now managed to demonstrate the feasibility of the virus engulfing and neutralizing nano-shells.

 Need for a broadly applicable antiviral treatment

 Viral infections affect millions of people every year and cause tremendous human suffering and costs to society. For approximately 70% of all WHO listed viruses, no treatment is available and the antiviral drugs that do exist must be applied very early after infection to be effective. The current COVID-19 pandemic is only one such example. The vision of the VIROFIGHT consortium is therefore to develop and test prototypes of nano-shells that may have the principal capacity to neutralize any given virus by engulfing them.

Experiments reveal virus engulfing and -neutralizing nature of the nano-shells

The team around Hendrik Dietz now demonstrated the virus-trapping concept of this approach. The researchers designed nano-shells using the concept of DNA-origami and by mimicking symmetry principles found in natural virus capsids. The artificial shells feature  internal cavity diameters up to 280 nm – big enough to fit most human viruses. When applying the nano-shells to human cell cultures infected with Adeno-associated virus in a first series of tests, the number of infected cells is significantly decreased. Cryo-EM images revealed that indeed the nano-shells neutralized the virus by engulfing viral particles inside their cavities. The results were recently published in the  journal Nature Materials.

DNA nano-shells trapping Hepatitis B virus particles

“These promising results mark an important milestone. But more work is still needed to validate this new avenue for antiviral technology” says Hendrik Dietz, professor of Biomolecular Nanotechnology at the Technical University of Munich (TUM) and Principal Investigator at TUM’s Munich School of BioEngineering. “The next steps for the VIROFIGHT team include how to trap and neutralize many different viruses without the need for antibodies, and testing the system in organisms.”

Ulrike Protzer, professor of Virology at TUM and co-author of the publication adds: „If the idea can be realized to simply eliminate viruses mechanically, this would be broadly applicable and thus an important breakthrough, especially for newly emerging viruses.”

Multidisciplinary consortium to further validate the approach

The interdisciplinary VIROFIGHT consortium integrates experts on supramolecular chemistry, molecular nanoengineering, and virology across Europe. Project partners are Aarhus University (Denmark), ARTTIC S.A.S. (France), ARTTIC Innovation GmbH (Germany), National Institute of Chemistry (Slovenia), University of Regensburg (Germany), Technical University of Munich (Germany) (coordinator). VIROFIGHT is supported by a 3.88 million Euro grant from the European Union’s Horizon 2020 funding programme. The project kicked-off on June 1st 2020 and will run until 31 May 2024.

* featured image shows Christian Sigl preparing nano-shells   for virus trapping. 
  photo by Daniel Delang / TUM