The vaccine against COVID-19 has been found to protect against infections and brain damage caused by the virus
Abstract: A new COVID-19 vaccine developed by researchers at CNB-CSIC appears to protect against brain infection and neurological symptoms associated with the coronavirus.
Source: University of Seville
Although respiratory pathology is the main impact of COVID-19, many patients also show important neurological symptoms, such as loss of smell (anosmia), headaches, malaise, cognitive loss, epilepsy, ataxia, and encephalopathy, among others.
However, this effect of the coronavirus on the nervous system has not been described in detail, and it is not known whether the vaccines developed against COVID-19 prevent the spread of SARS-CoV-2 to the central nervous system and protect against brain injury.
Now, using a mouse model susceptible to infection with the SARS-CoV-2 coronavirus, a multidisciplinary team of Spanish researchers led by Dr. Javier Villadiego and Dr. Juan José Toledo-Aral (IBiS, CIBERNED and Department of Medical Physiology and Biophysics Faculty of Medicine of Seville) and Juan García-Arriaza (Department of Molecular and Cellular Biology CNB-CSIC, CIBERINFEC and PTI Global Health CSIC), in collaboration with other groups from the University of Seville and the Spanish National Research Council (CSIC), demonstrate the ability of SARS-CoV-2 to infect different regions of the brain and causes brain damage and how the CNB-CSIC vaccine completely protects against brain infection.
These findings were published in The neuroscience of nature.
The researchers studied the evolution of viral infection in different regions of the brain, noting that viral replication occurs mainly in neurons, producing neuropathological changes such as neuronal loss, glial activation, and vascular damage.
“We conducted a very detailed anatomic-pathological and molecular study of brain regions and cell types infected by the virus. It’s amazing how the virus infects different areas and mainly neurons,” explains Javier Villadiego.
After establishing the SARS-CoV-2 brain infection pattern, the researchers evaluated the effectiveness of the CNB-CSIC-developed vaccine against COVID-19. To do this, they immunized mice with one or two doses of the MVA-CoV2-S vaccine, based on a modified vaccinia virus Ankara (MVA) that expresses the spike (S) protein of SARS-CoV-2, and analyzed the ability to protect against infection and brain damage.
“The results obtained were spectacular, showing that even a single dose of MVA-CoV2-S vaccine completely prevents SARS-CoV-2 infection in all brain regions investigated and prevents associated brain damage, even after re-infection with SARS-CoV- 2. virus. This shows the great efficacy and immunogenic power of the vaccine that induces sterilizing immunity in the brain,” says Juan García-Arriaza.
These results confirm previous data on the immunogenicity and efficacy of the MVA-CoV2-S vaccine in different animal models.
“We previously showed 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 strong immune response of antibodies that bind to the S protein of the virus and neutralizing antibodies against of different worrisome virus variants, as well as the activation of T lymphocytes, essential markers for infection control,” says Mariano Esteban, a CNB-CSIC researcher involved in the study.
The results have important long-term implications for understanding the infection caused by SARS-CoV-2. “The data we obtained on SARS-CoV-2 infection in the brain are compatible with the neurological pathology observed in patients with COVID-19,” says José López-Barneo, an IBiS researcher who participated in the publication.
“Our work is the first study of a vaccine that is 100% effective against brain damage caused by SARS-CoV-2 in a susceptible mouse, and the results obtained strongly suggest that the vaccine could prevent the persistent COVID-19 observed in several infected humans with SARS-CoV- 2,” says Juan José Toledo-Aral.
“The data reported in this study with MVA-CoV2-S vaccine-mediated complete inhibition of SARS-CoV-2 replication in the brain, together with previous studies published by the group and colleagues on the immunogenicity and efficacy of vaccines against different SARS-CoV-2 variants, support phase I clinical trials with such a vaccine or similar prototypes, in order to evaluate their safety and immunogenicity”, emphasize the authors of the study.
About this news about COVID-19 research
Original research: Open access.
“Full protection against SARS-CoV-2 brain infection and damage in susceptible transgenic mice by vaccine candidate MVA-CoV2-S” Javier Villadiego et al. The neuroscience of nature
Full protection against SARS-CoV-2 brain infection and damage in susceptible transgenic mice by vaccine candidate MVA-CoV2-S
Vaccines against SARS-CoV-2 have been shown to be safe and effective, but their protective efficacy against infection in the brain is not yet clear.
Here, in a susceptible transgenic K18-hACE2 mouse model of severe coronavirus disease 2019 (COVID-19), we report a spatiotemporal profile of SARS-CoV-2 infection and replication through the brain. Replication of SARS-CoV-2 in the brain occurs primarily in neurons, leading to neuronal loss, signs of glial activation, and vascular damage in mice infected with SARS-CoV-2.
One or two doses of a modified vaccinia virus Ankara (MVA) vector expressing the SARS-CoV-2 spike (S) protein (MVA-CoV2-S) provided full protection against SARS-CoV-2 cerebral infection, preventing virus replication in all areas of the brain and their associated damage. This protection was maintained even after re-infection with SARS-CoV-2.
These findings further support the use of MVA-CoV2-S as a promising vaccine candidate against SARS-CoV-2/COVID-19.