GHENT, Belgium -- When domesticated, llamas are multi-purpose animals used for their wool or as a pack animal for trekking and hiking. Did you ever think they’d play a role in battling the SARS-coV-2 pandemic?
Winter is the reason researchers have hope llamas could be used to find a coronavirus treatment. Saelens has been studying antiviral antibodies in llamas for nearly a decade. He says Winter isn’t necessarily unique. She was simply picked out of a herd.
“I don’t know exactly why. Probably it’s because she was rather gentle because you don’t want to be hit or spit by a llama if you approach him or her.”
It’s what happened after that has led researchers to a great discovery.
“We decided four years ago to immunize a llama with a mixture of proteins coming from the MERS coronavirus and the SARS coronavirus,” Saelens said.
Saelens, alongside a team from the University of Texas at Austin, found her immune system had a good response to both types of coronavirus developing antibodies against them. Now, they have confirmed she also has antibodies that can bind and neutralize the SARS-coV-2 virus.
“Binding the virus is one thing, but then being able to stop the virus from infecting a cell is what we call neutralizing the virus, and we found that the antibody could accomplish that.”
So what is it about llamas that makes them special? Llamas belong to a family called Camelids which also includes alpacas and camels. Saelens says this group produces a specialized class of antibodies called nanobodies.
“Those nanobodies can be extremely potent in binding to a target. They’re also small – small compared to a conventional antibody -- and they can reach parts of a virus that are more difficult to reach for.”
In other words, they’re small compared to your average human antibody, so they can target parts of the virus that are hidden and they’re very good at attaching to a specific unwanted target. Saelens says he and his team of researchers hope the antibodies can be used for a coronavirus treatment -- meaning it would help someone who has already been infected and is experiencing symptoms.
“And could for example prevent the person from becoming severely ill or improve the recovery phase of the person,” Saelens said.
According to Saelens, they’ve been testing the antibody mixture on hamsters. So far, they’ve had positive results. If all goes well, he’s optimistic they can start human clinical trials by the end of the year. Saelens says he finds it amusing Winter has become famous – especially considering she’s not aware of her celebrity status.
“She’s just another llama, I think, but she gave us very good nanobodies.”