Winter is a 4-year-old chocolate-coloured llama with spindly legs, ever-so-slightly askew ears and envy-inducing eyelashes. Some scientists hope she might be an important figure in the fight against the coronavirus.
She is not a superpowered camelid. Winter was simply the lucky llama chosen by researchers in Belgium, where she lives, to participate in a series of virus studies involving both SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome). Finding that her antibodies staved off those infections, the scientists posited that those same antibodies could also neutralize the new virus that causes COVID-19. They were right and published their results Tuesday in the journal Cell.
Scientists have long turned to llamas for antibody research. In the past decade, for example, scientists have used llamas’ antibodies in HIV and influenza research, finding promising therapies for both viruses.
Llamas’ antibodies are easily manipulated, said Dr Xavier Saelens, a molecular virologist at Ghent University in Belgium and an author of the new study.
In 2016, Saelens, Daniel Wrapp, a co-author of the new research, and Dr Jason McLellan, a structural virologist at the University of Texas at Austin, and other researchers looked to llamas — and, specifically, Winter — to find a smaller llama antibody “that could broadly neutralize many different types of coronavirus,” McLellan said.
They injected Winter with spike proteins from the virus that caused the 2002-03 SARS epidemic as well as MERS, then tested a sample of her blood. And while they couldn’t isolate a single llama antibody that worked against both viruses, they found two potent antibodies that each fought separately against MERS and SARS.
The researchers were writing up their findings when the new coronavirus began to make headlines in January. They immediately realized that the smaller llama antibodies “that could neutralize SARS would very likely also recognize the COVID-19 virus,” Saelens said.
It did, the researchers found, effectively inhibiting the coronavirus in cell cultures.
The researchers are hopeful the antibody can eventually be used as a prophylactic treatment, by injecting someone who is not yet infected to protect them from the virus, such as a health care worker. While the treatment’s protection would be immediate, its effects wouldn’t be permanent, lasting only a month or two without additional injections.
