While Fifi, the llama, is chewing grass on a pasture in Reading, her immune system has provided the basis for a breakthrough in the treatment of coronaviruses.
Scientists at the Rosalind Franklin Institute in the UK have used Fifi̵
The resulting lama-based, Covid-specific “antibody cocktail” could be included in clinical trials within months.
The development is published in Nature Structural and Molecular Biology.
They are “technical” llama antibodies that are relatively small and structured much more simply than the antibodies in our own blood. This size and structure means that they can be “redesigned” in the laboratory.
Unlock corona virus
Professor James Naismith, director of the Rosalind Franklin Institute – and the lead researcher – described the technique as cutting a key that fits the coronavirus lock.
“With the llama’s antibodies, we have keys that don’t quite fit – they lock, but don’t turn around,” he said.
“So we take this key and use molecular biology to polish parts of it until we cut a suitable key.”
Antibodies are part of the so-called adaptive immune system; They are molecules that essentially transform in response to an invading virus or bacteria.
“If you get infected again,” explained Prof. Naismith, “your body will look for one [virus particles] with antibodies around them and destroys them. ”
This type of immunotherapy essentially strengthens a patient’s immune system with antibodies that have already adapted to the virus.
There is already evidence that antibody-rich blood drawn from people who have recently recovered from the coronavirus could be used for treatment. The key trick with this Lama-derived antibody therapy, however, is that the scientists can produce coronavirus-specific antibodies on demand.
The small revised part of the llama antibody is also known as the nanobody, said Prof. Naismith.
“In the laboratory, we can make nanobodies that kill the living virus very well – better than almost anything we’ve seen,” he added. “They are incredibly good at killing the virus in culture.”
The nanobodies do this by binding or binding the so-called “spike protein” to the outside of the virus capsule. Disabling this tip prevents it from accessing human cells.
“Essentially, we do in the laboratory what all immune systems in the body do,” said Prof. Naismith.
“And we can do that very quickly. If the virus suddenly changes or we get a new virus, we can construct new nanobodies in the laboratory.”
The team plans to test its prospective therapy in animal trials this summer to begin clinical trials later in the year.
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