Nanoparticles from combustion engines can activate viruses that are dormant in in lung tissue cells. This is the result of a study by researchers of Helmholtz Zentrum München, a partner in the German Center for Lung Research (DZL), which has now been published in the journal ‘Particle and Fibre Toxicology’.

To evade the immune system, some viruses hide in cells of their host and persist there (latent infection). If the immune system becomes weakened or if certain conditions change, the viruses become active again, begin to proliferate and destroy the host cell. A team of scientists now report that nanoparticles can also trigger this process. From previous model studies it is already known that the inhalation of nanoparticles has an inflammatory effect and alters the immune system.

The scientists showed that an exposure to nanoparticles can reactivate latent herpes viruses in the lung. Specifically, they tested the influence of nanoparticles typically generated by fossil fuel combustion in an experimental model for a particular herpes virus infection. They detected a significant increase in viral proteins, which are only produced with active virus proliferation. Moreover, further experiments with human cells demonstrated that Epstein-Barr viruses are also ‘awakened’ when they come into contact with the nanoparticles.

In further studies, the research team would like to test whether the results can also be transferred to humans. Many people carry herpes viruses, and patients with idiopathic pulmonary fibrosis are particularly affected. If the results are confirmed in humans, it would be important to investigate the molecular process of the reactivation of latent herpes viruses induced by particle inhalation. Then the scientists could try to use this pathway therapeutically.

Special cell culture models shall therefore elucidate the exact mechanism of virus reactivation by nanoparticles. In addition in long-term studies the scientists would like to investigate to what extent repeated nanoparticle exposure with corresponding virus reactivation leads to chronic inflammatory and remodeling processes in the lung.


Further Information / Sources:

Original Publication:
Sattler C, Moritz F, Chen S, Steer B, Kutschke D, Irmler M, Beckers J, Eickelberg O, Schmitt-Kopplin P, Adler H, Stoeger T. (2016): Nanoparticle exposure reactivates latent herpesvirus and restores a signature of acute infection. Particle and Fibre Toxicology, DOI 10.1186/s12989-016-0181-1

 Press release from the "Helmholtz Zentrum München"