Japanese scientists have reportedly developed a vaccination strategy that, if proven successful, could provide immunity against a vast variety of coronaviruses, including the one that causes Covid-19.
According to reliable reports, development of a vaccine that is more widely applicable has been the primary goal of researchers, given that some of the existing vaccines have been proven to be less effective against new strains of Sars-CoV-2.
The approach developed by researchers in Japan might possibly be utilized to deliver protection against any new pandemics that might originate from different coronaviruses. Their approach, outlined in a newly published study in the Journal of Experimental Medicine, entails genetically modifying proteins from the Sars-CoV-2 virus.
The spike protein of the virus, which comprises a receptor-binding domain that binds to the ACE2 receptor on living human cells, was at the center of the study. The virus penetrates cells and multiplies after the spike protein binds to ACE2.
The head portion of the receptor-binding domain is highly specialized, while the core area of the receptor-binding domain is similar across other coronaviruses.
Vaccine-induced immunity usually includes the development of antibodies against the specialized head region of the coronavirus, making the protection extremely specific to that coronavirus.
To circumvent this predicament, scientists from Japan's Osaka University have genetically modified the receptor-binding domain of spike protein to have sugar molecules connected to the head region.
Mice exposed to these altered proteins generated a higher proportion of antibodies against the core area rather than the head region, as would be expected.
The antibodies they created were what the scientists call widely neutralizing, and in testing, they were shown to neutralize not only Sars-CoV-2 but also Sars-CoV-1, which had triggered the 2002 Sars outbreak.
They were also effective against three related coronaviruses in pangolins and bats, which is significant since coronaviruses that are now prevalent in some species may infect humans in the future.