Gardênia Vargas (CDTS/Fiocruz)
In a partnership with Instituto D’Or (Idor) and the Federal University of Rio de Janeiro (UFRJ), a study by the Center for Technological Development in Health (CDTS/Fiocruz) observed that the virus responsible for the Covid-19 pandemic, the SARS-CoV-2, can infect neural cells and create brain damage. Organized by Faperj and published in preprint, the project started with the analysis of the neural tissue of a patient who died due to the disease.
“We had observed that in the cerebral parenchyma, that is, in the gray matter itself, the virus had not been detected. However, it was found in the lining of the cells inside the skull”, explains Thiago Moreno L. Souza, virologist and researcher leading the Fiocruz Group.
With this piece of data in hand, the groups began a series of laboratory experiments to evaluate whether the neurons actually did get infected. The Fiocruz Group is responsible for reviewing the laboratory tests of the clinical case, experimental infections, and viral quantification. The Idor and UFRJ Group, led by neuroscientist Stevens Rehen, is in charge of prospecting the clinical case and preparing the 3D neuronal cellular models.
“What we have discovered is that neurons allow the virus in. The virus can then produce its own genetic material inside the cell, but the generated viral progeny, that is, the replication cycle, does not take place. What we understood in the conclusion of this study is, therefore, that this replication inside the neuron is abortive: once inside, there is no more replication, which means no local infection. However, this is not enough to not cause a lesion. The simple presence of the virus in the nervous tissue is harmful to the brain cells”, says Moreno.
Covid-19 was initially described as a viral infection of the respiratory tract. It is now known that several other biological systems are affected, including the central nervous system (CNS). Neurological manifestations, such as strokes, encephalitis, and psychiatric conditions have all been reported in patients with the disease, but the few existing studies are still being evaluated and debated. This makes research draw attention to the potential of this virus when it comes to causing a more serious and lethal disease than the one that affects the lungs.