Summary: 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 tract pathology is the main impact of Covid-19, many patients also exhibit important neurological symptoms such as loss of smell (anosmia), headache, malaise, cognitive loss, epilepsy, ataxia and encephalopathy.
However, this effect on the nervous system by the coronavirus has not been extensively characterized, and it is unknown whether vaccines developed against COVID-19 prevent SARS-CoV-2 from spreading to the central nervous system and provide protection from brain injury.
Now, using a mouse model susceptible to SARS-CoV-2 coronavirus infection, Dr. Javier Villatico and Dr. A multidisciplinary team of Spanish researchers led by Juan José Toledo-Aral (IBiS, CIBERNED and Department of Clinical Physiology and Biophysics). Faculty of Medicine of Seville) and Juan García-Arriaza (Department of Molecular and Cellular Biology of CNB-CSIC, CIBERINFEC and PTI Global Health of CSIC), in collaboration with other groups of the University of Seville and the Spanish National Research Council (CSIC), in collaboration with different groups of the SARS-CoV-2 brain. Demonstrates the ability to infect regions and induce brain damage and how the CNB-CSIC vaccine completely protects against brain infection.
These findings have been published Natural neuroscience.
Researchers have studied the evolution of viral infection in different brain regions, mainly in neurons where viral replication occurs, producing neuronal changes such as neuronal loss, glial activation and vascular damage.
“We have carried out a very detailed anatomical-pathological and molecular study of the brain regions and the types of cells infected by the virus. It is remarkable how the virus affects different regions and mainly neurons,” explains Javier Villatico.
After establishing the pattern of infection in the brain by SARS-CoV-2, the researchers evaluated the effectiveness of the vaccine against COVID-19 developed at CNB-CSIC. To do this, they vaccinated mice with one or two doses of an MVA-CoV2-S vaccine based on a modified vaccinia virus Ankara (MVA) expressing the spike (S) protein of SARS-CoV-2. Protect against infection and brain damage.
“The results obtained are spectacular, demonstrating that administration of even a single dose of the MVA-CoV2-S vaccine completely inhibits SARS-CoV-2 infection in all brain regions examined. The virus. This demonstrates the excellent efficacy and immunogenicity of the vaccine, which induces a neutralizing immune response in the brain. is stimulating,” says Juan Garcia-Arriaza.
These results reinforce previous data on the immunogenicity and efficacy of the MVA-CoV2-S vaccine in various animal models.
“We previously showed in a series of publications that the MVA-CoV2-S vaccine we developed at CNP-CSIC induces a potent immune response in three animal models (mouse, hamster and macaque) with antibodies binding to the S protein. Neutralizing antibodies against the virus and different strains of the virus, as well as 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 epidemiology caused by SARS-CoV-2. “The data we obtained on SARS-CoV-2 infection in the brain are compatible with the neuropathology observed in patients with COVID-19,” says IBiS researcher José López-Bernio, 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, and the results strongly suggest that the vaccine will prevent the persistent COVID-19 seen in many infected people. With SARS-CoV-2, ” says Juan José Toledo-Aral.
“The data presented in this study with complete inhibition of SARS-CoV-2 replication in the brain mediated by the MVA-CoV2-S vaccine are consistent with previous studies published by the team and collaborators, and with the different immunogenicity and efficacy of the vaccine against SARS-CoV-2 variants, their safety and immunogenicity. Phase I clinical trials with such a vaccine or similar prototypes are supported to assess efficacy,” the study’s authors emphasize.
About this covid-19 research news
Original Research: Open access.
“Full protection against SARS-CoV-2 brain infection and damage in susceptible transplant mice conferred by the MVA-CoV2-S vaccine candidateJavier Villatico et al. Natural neuroscience
Full protection against SARS-CoV-2 brain infection and damage in susceptible transplant mice conferred by the MVA-CoV2-S vaccine candidate
Vaccines against SARS-CoV-2 have been shown to be safe and effective, but their protective efficacy against infection in the brain is still unclear.
Here, we report a spatiotemporal description of SARS-CoV-2 infection and replication through the brain in a transgenic K18-hACE2 mouse model with variable susceptibility to acute coronavirus disease 2019 (COVID-19). SARS-CoV-2 brain replication occurs primarily in neurons, leading to neuronal loss, signs of glial dysfunction, 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) confers full protection against SARS-CoV-2 cerebral infection and inhibits viral replication in all. Regions of the brain and associated damage. This protection was maintained after SARS-CoV-2 infection.
These findings further support the use of MVA-CoV2-S as a promising vaccine candidate against SARS-CoV-2/COVID-19.