Acquired Immunity Protects Macaques Well Against COVID-19 - Research

2023 Author: Abraham Higgins | [email protected]. Last modified: 2023-11-27 23:16

Acquired immunity protects macaques well against COVID-19 - research

Scientists have tested in animal experiments how effective neutralizing antibodies against the SARS-CoV-2 virus are.

Photo: CC0 Public Domain

Can new vaccines really protect against COVID-19? Do antibodies against SARS-CoV-2 coronavirus, which were developed after illness, prevent re-infection? To date, scientists have been able to answer these questions only with the example of monkeys. Two studies are published in the journal Science. Their results inspire optimism in scientists, but they cannot currently be projected onto humans.

Dan H. Barouch, director of the Center for Virology and Vaccine Research, Beth Israel Medical Center, Boston, USA, led the two groups of scientists who investigated immunity in rhesus monkeys.

The first group of scientists focused on the effects of six experimental DNA vaccines that are supposed to induce the development of immunity against the S-protein of the SARS-CoV-2 coronavirus. DNA vaccines contain circular DNA (plasmid) that is not included in the chromosome. This DNA contains information about the proteins of the virus, to which a person must develop immunity.

First, scientists found that vaccines caused antibodies in rhesus monkeys. They then exposed 25 immunized animals and 10 control monkeys to the virus.

In eight vaccinated macaques, the coronavirus was not detected in the body. The rest of the vaccinated animals had much lower viral loads than those who did not receive the vaccine. Scientists have concluded that neutralizing antibodies against SARS-CoV-2 can protect macaques from disease: alleviate infection or completely prevent it.

In the second study, scientists analyzed the effectiveness of the immunity that develops in macaques after suffering from COVID-19. Nine animals suffered the infection, all of them were found to have antibodies to the virus. Later, scientists tried to infect macaques with coronavirus again. They called the protection of recovered animals from the virus "almost complete": this model demonstrated expressive natural immunity.

The scientists point out that their findings are encouraging about the future effectiveness of COVID-19 vaccines.