Novel vaccine against corona and flu viruses
The SARS-CoV-2 coronavirus and influenza A virus (IAV) are well-known viruses of zoonotic origin that have caused global pandemics with serious consequences for human health and the economy. There is an ongoing medical need for vaccines against such pathogens. A herpes virus can help. Because, as researchers are now reporting, they have developed a novel vaccine against corona and flu viruses based on the cytomegalovirus.
We encounter viruses mostly as pathogens. But virus-based vaccination platforms can also help protect against various diseases. Researchers have now developed a novel vaccine against various respiratory viruses based on the cytomegalovirus. A single dose of the vaccine, which consists of a cytomegalovirus to which a gene from the coronavirus or influenza A has been added, efficiently protected mice from the respiratory infections.
From the family of herpesviruses
As in a current Message of the Helmholtz Center for Infection Research (HZI) in Braunschweig, vector-based vaccines experienced their public breakthrough with the development of several COVID-19 vaccines. In this technology, harmless helper viruses deliver the genetic code for an antigen into host cells, which in turn produce the antigen and present it on their surface, triggering an immune response.
While the SARS-CoV-2 vector vaccines are based on modified adenoviruses, researchers led by Prof. Luka Cicin-Sain, head of the HZI department “Viral Immunology”, have identified a promising alternative candidate for a vector-based vaccine platform: the cytomegalovirus (CMV ).
According to the information, CMV is a member of the herpesvirus family, which usually causes only mild symptoms when infected and can remain in the body for a long time.
“Protective effect against influenza and SARS-CoV-2”
In the current study, the scientists of the HZI together with national and international partners, including the German Center for Infection Research (DZIF), the German Primate Center – Leibniz Institute for Primate Research (DPZ), the Technical University of Braunschweig and the University Rijeka in Croatia, worked with murine CMV (MCMV) in an animal infection model, since human CMV cannot infect mice.
“It is a peculiarity of CMV that it causes a strong and persistent activation of T-cells, which help to keep the virus under control,” explains Cicin-Sain. In order to use MCMV as a vector to protect against other respiratory infections, the researchers integrated genetic sequences of influenza A or SARS-CoV-2 proteins into the MCMV genome. After the injection of these carrier viruses, the mice developed an immune response that protected them from infection with influenza or SARS-CoV-2.
As explained in the release, the adaptive immune system consists of two parts: antibody-producing B cells make up the humoral arm, while T cells make up the cellular arm. According to the experts, both arms should be addressed for an efficient and long-lasting immune response.
“While the immune response to CMV is dominated by a T-cell response, we show in our study that this vector can also induce a protective effect against influenza and SARS-CoV-2 through antibodies,” says Cicin-Sain. For SARS-CoV-2, the scientists were also able to show that the antibodies were active against different variants of the virus, such as alpha (B.1.1.7) and beta (B.1.351).
The quality of the antibodies improved
According to the data, not only did a single dose of the CMV vaccine provide long-term protection, but the quality of the antibodies improved over time through a process called affinity maturation.
“Permanent immunity usually requires multiple vaccine injections. With our platform, we observe them with a single dose,” explains Yeonsu Kim, PhD student in the Viral Immunology department and first author of the study. “This makes CMV an ideal vector candidate for achieving good protection with simple logistics,” says the researcher.
“Overall, we show that our vaccine platform can generate strong antibody-mediated protection against two different respiratory viruses. Therefore, we believe that the effect is not specific to the target virus, but that the CMV platform can also be applied to other viruses,” says Cicin-Sain. “The approach has the potential to go through the necessary further preclinical and clinical development steps.”
Author and source information
This text corresponds to the requirements of medical specialist literature, medical guidelines and current studies and has been checked by medical professionals.
- Helmholtz Center for Infection Research: HZI research team develops novel vaccine against corona and influenza viruses based on the cytomegalovirus, (accessed: January 18, 2022), Helmholtz Center for Infection Research
- Yeonsu Kim*, Xiaoyan Zheng*, Kathrin Eschke*, M. Zeeshan Chaudhry*, Federico Bertoglio, Adriana Tomić, Astrid Krmpotić, Markus Hoffmann, Yotam Bar-On, Julia Boehme, Dunja Bruder, Thomas Ebensen, Linda Brunotte, Stephan Ludwig, Martin Messerle, Carlos Guzman, Ofer Mandelboim, Michael Hust, Stefan Pöhlmann, Stipan Jonjić, Luka Čičin-Šain (*contributed equally): MCMV-based vaccine vectors expressing full-length viral proteins provide long-term humoral immune protection upon a single-shot vaccination; in: Cellular & Molecular Immunity, (published: 2022-01-07), Cellular & Molecular Immunity
This article contains general advice only and should not be used for self-diagnosis or treatment. He can not substitute a visit at the doctor.