The antibody was identified by the Duke Human Vaccine Institute (DHVI) team and tested on animal models at UNC-Chapel Hill. The researchers published their findings in the journal Science Translational Medicine.
“This antibody has the potential to be therapeutic in the current epidemic,” said another senior author Barton Haynes, MD, Director of DHVI. “It may also be available for future epidemics if or when other coronaviruses jump from their natural animal hosts to humans.”
Haynes and colleagues at DHVI isolated the antibody by analyzing blood from a patient who had acquired the original SARS-CoV-1 infection that caused the SARS epidemic in the early 2000s and the current COVID-19 patient.
They identified more than 1,700 antibodies produced by the immune system to bind to specific sites on certain viruses to prevent the pathogen from infecting cells. As viruses mutate, many binding sites change or are eliminated, leaving antibodies ineffective. But often there are sites in the virus that remain unchanged despite mutations. The researchers focused on antibodies that target these sites because they can be very effective in different generations of the virus.
Of the 1,700 antibodies in the two individuals, Duke researchers found 50 antibodies that had the ability to bind to both SARS-CoV-1 virus and SARS-CoV-2 virus, which causes COVID-19.
Further analysis found that one of those cross-linking antibodies was particularly potent — able to bind to several animal coronaviruses in addition to the two human infectious pathogens.
“This antibody binds to the coronavirus at a site that has survived numerous mutations and variations,” Haynes said. “As a result, it can neutralize a wide variety of coronaviruses.”
Once the antibody was isolated, the DHVI team turned to UNC researchers with expertise in animal coronaviruses. A UNC group led by another senior author Ralph S. Baric, Ph.D., a professor of epidemiology at the UNC Gillings School of Global Public Health, tested it in mice to determine if it could effectively prevent infections or minimize infections that occurred.
They found that it did both. When administered prior to infection of animals, the antibody protected mice from developing SARS, COVID-19 and its variants, such as Delta, and many animal coronaviruses that can cause human pandemics.
“The findings provide a model for the rational design of universal vaccine strategies that are variant-resistant and provide broad protection against known and emerging coronaviruses,” Baric said.
Antibody administered after infections reduced severe lung symptoms compared to animals not treated with the antibody.
“Therapeutic activity even after infection of mice suggests that this could be a treatment used in the current pandemic but also stored to prevent the spread of a future SARS virus epidemic,” he said. David Martinez, Ph.D., PhD researcher at the Department of Epidemiology, Gillings School, UNC.
“This antibody could be harnessed to prevent SARS-CoV-3 or SARS-CoV-4,” Martinez said.
Source: The Nordic Page