Llama antibodies may aid treatment against coronavirus
Antibodies from a llama in Belgium could provide a treatment against the coronavirus, which has infected nearly 4 million people and left more than 250,000 dead. Scientists in the United States and Belgium have published a paper on their findings which is under peer-review. The new treatment may be effective even if Covid-19 mutates.
The llama that may save the world is called Winter. She is four years old and lives on a farm in the Belgian countryside along with around 130 other llamas and alpacas.
Researchers in the United States and Belgium have created an antibody which they claim protects human cells from Covid-19.
It “glues” on the Covid-19 protein (which mechanically breaks into and infects host cells) and blocks it from infecting more cells.
More than 30 scientists from the University of Texas at Austin, the National Institutes of Health (US) as well as Belgium’s VIB research institute and Ghent University have been working on this new drug. Their findings were published on 5 May in the scientific journal, Cell, for peer-review.
The antibody they discovered was obtained by linking two copies of a special kind of antibody that Winter produced when injected with SARS-CoV-2, the virus that causes Covid-19.
“This is one of the first antibodies known to neutralise SARS-CoV-2,” said Jason McLellan, associate professor of molecular biosciences at UT Austin and co-senior author.
He said vaccines have to be given a month or two before infection to provide protection.
“But with antibody therapies, you’re directly giving somebody the protective antibodies and so, immediately after treatment, they should be protected,” he added.
This would be especially helpful for vulnerable groups such as elderly people.
The llama produced two types of antibodies, one similar to human antibodies and one which is much smaller, called “nanobodies”. They are the ones of interest to the scientists as they are “more versatile”.
“They have a single piece of protein that binds to the virus. It makes it easier for us to play with and engineer new drugs out of it,” explained Professor Nico Callewaert, VIB Institute’s director of medical biotechnology at Ghent University and co-author of the paper.
Callewaert told RFI that the nanobodies – reproduced in labs – can be connected to human antibodies enabling the new drug to function correctly in the human body.
The nanobodies can be nebulised and used in an inhaler.
“That makes them potentially really interesting as a drug for a respiratory pathogen because you’re delivering it right to the site of infection,” said Daniel Wrapp, a graduate student in McLellan’s lab and co-first author of the paper.
Years of research on coronavirus
The scientists were studying two coronaviruses in 2016 with Winter as part of their experiment.
She was then injected with a piece of Sars virus in a process similar to humans getting shots to immunise them against a virus.
“After the new coronavirus appeared in 2019, the genome was published by Chinese scientists in January 2020. We quickly saw the similarities between Sars and SARS-Cov-2,” said Callewaert.
Because of the four years of work already accomplished, the scientists were able to move quickly with building a neutralising antibody against SARS-CoV-2 and publish their findings in the Cell scientific journal.
Clinical trials have not started yet. The antibody developed by the scientists has successfully protected human cells and cells taken from the African Green monkey.
Experiments are ongoing
“We have a good knowledge of where the antibody binds on the virus and this place is apparently not likely to change readily due to mutation,” he added. “Evidence of this was shown in 10,000 sequences of the virus genome that have so far been reported.”
According to Callewaert, the teams in the United States and Belgium are doing everything they can to go into human trials before the end 2020.
“We are working very hard to squeeze everything into less than a year as it usually takes five to six years before you get the first human trials data.”
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