Several vaccinations have been approved more than a year after the COVID-19 epidemic began, due to extraordinary global research efforts.
These first-generation vaccinations provide a lot of promise and are crucial in the fight against the virus. However, there are still unanswered issues about the durability of the immune response and the need for a booster. Controlling the pandemic also necessitates the vaccination of billions of individuals.
Manufacturing enough dosages to safeguard the entire world’s population, however, is a significant issue. That is why vaccine research is continuously going on in order to produce more candidate vaccines and satisfy these different difficulties.
Researchers from the Vaccination Research Institute (VRI) (Inserm/Université Paris-Est Créteil), CEA, and Université Paris-Saclay are working on a monoclonal antibody-based vaccine that targets circulating immune cells called dendritic cells.
As the research has shown in various infection models, these cells play a critical role in activating the immune system by inducing a powerful and long-lasting antibody and cellular response. The SARS-CoV-2 protein is linked to the monoclonal antibody, which activates dendritic cells.
Furthermore, a clinical research investigating the safety and immunogenicity of a preventative HIV vaccine using this dendritic cell targeting vaccine technology is now in phase I.
Restimulate the production of neutralizing antibodies
The researchers began their investigation, which was published in Nature Communications, by looking at the efficacy of their candidate vaccine to generate anti-COVID-19 “booster” responses in convalescent animals (those who had caught SARS-CoV-2 six months prior).
They indicate that the vaccination is safe and efficient, causing a significant rise in neutralizing antibodies. When exposed to the virus for the first time, convalescent and vaccinated animals have an undetectable viral load or eliminate the virus faster (within three days) than unvaccinated convalescent animals or control animals who have never been infected.
As a result, a single dose of this vaccine offers greater protection against reinfection than natural immunity. In addition, the vaccinated animals were protected from infection-related pulmonary problems.
Finally, the researchers have already modified the proposed vaccination to make it effective against newly discovered variations. The antibodies produced by the vaccination are capable of neutralizing the alpha version (B.1.1.7) extremely well in the laboratory, as well as neutralizing the beta variation considerably (B.1.351). As a result, the vaccine produced from the first strain circulating in early 2020 is capable of generating an antibody response that neutralizes both the new variations tested and the original strain.
To summarize, this research shows that a single dose of the candidate vaccine, given without adjuvant, stimulates the production of neutralizing antibodies capable of controlling the virus during reinfection. This is more effective than natural immunity in terms of preventing reinfection. As a result, this vaccine might be used to augment the current COVID vaccinations. The findings of this study show that it might be especially beneficial for persons who are recuperating from or have already been vaccinated but whose immune response has begun to wane in order to boost their immunity. This vaccine might be beneficial for vulnerable persons or for immunizing youngsters due to the strong understanding of subunit vaccine safety.
Clinical studies are scheduled for 2022 with convalescent patients or those who have already received a first-generation vaccination. They will also be carried out in individuals who have never been exposed to either vaccine or the virus.