Friday, May 8, 2020

Scientists Say Llama Antibodies Could Be Key to Defeating COVID

Scientists Say Llama Antibodies Could Be Key to Defeating COVID



"This is one of the first antibodies known to neutralize SARS-CoV-2."

According to a new study by an international team of researchers, antibodies found in the blood of llamas were able to stave off coronavirus infections.

“This is one of the first antibodies known to neutralize SARS-CoV-2,” Jason McLellan, from the University of Texas at Austin and co-author of the study, said in a statement.

The researchers built on previous research from four years ago in which they found that the antibodies from a then 9-month-old llama named Winter were able to neutralize both SARS-CoV-1 and MERS-CoV viruses over six weeks.

Luckily, the antibodies from Winter — who’s now four years old — also staved off SARS-CoV-2, the virus that causes COVID-19. Winter is a 4-year-old chocolate-colored 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 novel coronavirus.  “Vaccines have to be given a month or two before infection to provide protection,” McLellan said in the statement. “With antibody therapies, you’re directly giving somebody the protective antibodies and so, immediately after treatment, they should be protected.”

The Llama and the Nanobody

The molecule the team produced, and for which they obtained a structure, represents only the extracellular portion of the spike protein, but it is enough to elicit an immune response in people, and thus serve as a vaccine.



“The antibodies could also be used to treat somebody who is already sick to lessen the severity of the disease,” McLellan added.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 and MERS. 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.

Surprisingly, this isn’t the first time llamas have been used in antibody research, as The New York Times reports. Llama antibodies have been used in work related to HIV and influenza, where they helped discover promising therapies.



This is a 3D atomic scale map, or molecular structure, of the 2019-nCoV spike protein. The protein takes on two different shapes, called conformations—one before it infects a host cell, and another during infection. This structure represents the protein before it infects a cell, called the prefusion conformation.

Thanks to the llamas’ antibodies’ small size, they can connect with different parts of the virus more easily.  “The antibodies could also be used to treat somebody who is already sick to lessen the severity of the disease,” McLellan added.
“The binding of this antibody to spike is able to prevent attachment and entry, which effectively neutralizes the virus,” Daniel Wrapp, Dartmouth Ph.D. candidate and co-author, explained in the statement.

Scientists are hopeful a treatment plan for the newly infected in the form of antibody therapies is particularly promising.

No comments: