The presence of Covid-19 has sometimes been observed in the brains of certain patients. However, as reported by our colleagues from New Scientist, “the ACE2 receptor, which the virus normally uses to enter cells, is barely detectable in the brain, unlike the cells that line the nose, mouth and lungs” . The researchers therefore sought to find out how SARS-CoV-2 managed to migrate to the brain.
A team from the Institut Pasteur may have some leads to answer this question. According to a study, led by Chiara Zurzolo and published Wednesday in the journal Science Advancesthe virus would build tiny tunnels through which it could easily pass from the nose to the brain.
A drug to block this process
To do this, the scientists placed human brain cells and cells lining the nose in particular. While the brain cells, which do not have ACE2 receptors, should not have been infected, the scientists found, after incubation, that they had indeed been.
By observing the cells of the nose, using an electron microscope, they then discovered that the viruses had stimulated them “to develop tiny tubes, called nanotubes, which formed connections with brain cells”. . This is how SARS-CoV-2 would travel to the brain.
So far, these tiny tunnels have only been observed in the laboratory. But if it turns out that the virus does circulate in this way inside the human brain, this discovery could lead to the development of a drug to block this process. “At the moment, we do not have a specific molecule blocking the nanotubes, but we are screening to find one”, announced Chiara Zurzolo.