Could Antibodies Found In Llamas Help US To Defeat Covid-19?

Researchers at the McLellan Lab in Austin, Texas, are using llama antibodies to attack ‘spike proteins’ found on the surface of the SARS-CoV-2 virus

- Jason Goodyer

“You could administer antibody treatments to people who are infected, and it would reduce the disease burden.”

What is a spike protein and what is its function?

Daniel Wrapp A spike protein is a protein that decorates the surface of a coronavirus. Its job is to attach that virus to a host cell by binding to a receptor [on the host cell’s surface]. Once it’s attached, it fuses the viral membrane with the host cell membrane so that the virus can enter into the host cell and begin the process of replication. The spike protein is the main machine that the virus uses to enter into our cells. So, without the spike functioning properly on the surface of a virus, the virus is neutralised and is noninfectious.

Why did you focus on llamas?

Camelids, which is a family that includes camels, llamas, alpacas and a couple of other animals, produce this special class of small antibodies [proteins produced by the immune system to fight off harmful bacteria and viruses], which are sometimes called nanobodies. Camelid antibodies are about half the size of the conventional antibodies that you or I would produce, and because of that small size, they have enhanced stability and they’re also capable of binding to small crevices or pockets that larger antibodies wouldn’t otherwise be able to bind to. [This is why the llama antibodies can bind to the spike proteins on coronaviruses.]