The SARS-Cov-2 virus mainly affects the respiratory system but it also causes neurological symptoms which have been little studied. In addition, it is not known whether covid vaccines protect the central nervous system against the virus and prevent brain lesions.
Now, a team of researchers from the Institute of Biomedicine of Sevilla (IBiS) and the National Center of Biotechnology (CNB-CSIC) have just published a study demonstrating that the SARS-CoV-2 infects and damages neurons in different regions of the brain, and that it such damage is “completely prevented” by the covid vaccine developed by the CNB. Details of the research, conducted in a mouse model, were published Monday in the journal ‘Nature Neuroscience.
Many of the patients infected with SARS-CoV-2 manifest. significant neurological symptoms, such as loss of smell (anosmia), headaches, malaise, cognitive loss, epilepsy, ataxia and encephalopathy. In this work, the authors have studied how the viral infection evolves in different brain regions.
“We have carried out a anatomopathological study and molecular study of the brain regions and cell types that have been infected by the virus, being remarkable how the virus mostly infects neurons in different areas”, says the co-director of the study. Javier Villadiego, of IBiS.
Once the pattern of infection of the brain by coronavirus was established, the researchers evaluated the efficacy of the vaccine against the covid-19 developed by CNB-CSIC.
To do so, they immunized mice with one or two doses of the MVA-CoV2-S vaccine, based on the modified vaccinia virus Ankara (MVA). expressing the SARS-CoV-2 spicule protein (S).
“The results obtained were. spectacular, demonstrating that even the administration of a single dose of MVA-CoV2-S vaccine completely prevents SARS-CoV-2 infection in all brain regions studied, and prevents the associated brain damage, even after reinfection with the virus, which demonstrates the high efficacy and immunogenic potency of the vaccine that induces a sterilizing immunity in the brain,” stresses Juan Garcia Arriaza, co-author of the study and CNB researcher.
These results reinforce previous data from immunogenicity y effectiveness of the MVA-CoV2-S vaccine in several animal models.
“We had previously demonstrated in a series of publications that the MVA-CoV2-S vaccine that we developed at CNB-CSIC induces in three animal models (mouse, hamster and macaque). a potent immune response of antibodies antibodies to the S protein of the virus and neutralizing antibodies against different variants of virus concern, as well as T lymphocyte activation, essential markers for the infection control.” notes Mariano Esteban, CNB-CSIC researcher.
The results generated have important long-term implications for understanding the infection caused by SARS-CoV-2.
“The data we have obtained on SARS-CoV-2 infection in the brain are. compatible with neurological pathology observed in patients with covid-19,” highlights José López Barneo, IBiS researcher.
“Our work is the first study of a vaccine that has an 100% efficacy against brain damage caused by SARS-CoV-2 in a mouse. susceptible, and the results obtained strongly suggest that the vaccine could prevent the persistent covid-19 observed in many people infected with SARS-CoV-2,” he notes. Juan José Toledo Aral, co-director of the study.
For the authors, the results of the study support the conduct of Phase I clinical trials with the CNB vaccine or similar prototypes to evaluate its safety and immunogenicity.