Llama antibodies can potentially provide treatment against Covid-19. Researchers at the Rosalind Franklin Institute have discovered nanobodies, a simple form of antibody generated by llamas and camels. This can effectively target the Sars-CoV-2 virus that causes Covid-19.
According to the studies conducted, short chains of the molecules, which can be produced on a large scale in laboratories, can significantly reduce signs of Covid-19 when given to infected animal models.
The latest discovery can potentially provide a cheaper and easier alternative to human antibodies taken from recovered from Covid-19 patients, as the nanobodies tightly bind to the virus and neutralize it in the laboratory.
During the pandemic, human antibodies have been used in serious cases, though they are used by infusion through a needle in a hospital.
Professor Miles Carroll, deputy director of the National Infection Service, Public Health England (PHE) said it is in its early stage though it opens up the possibility for using nanobodies in treatments for Covid-19.
He further added, “We believe the unique structure and strength of the nanobodies contribute to their significant potential for both the prevention and treatment of Covid-19 and look forward to working collaboratively to progress this work into clinical studies.”
According to Professor Ray Owens, head of the protein production at the Rosalind Franklin Institute and lead author of the research, “Nanobodies have a number of advantages over human antibodies. They are cheaper to produce and can be delivered directly to the airways through a nebulizer or nasal spray, so can be self-administered at home rather than needing an injection. This could have benefits in terms of ease of use by patients but it also gets the treatment directly to the site of infection in the respiratory tract.”
Researchers generated nanobodies by injecting a portion of the spike protein into a llama called Fifi. The spike protein resides on the outside of the virus and is responsible for binding to human cells so it can infect them.
Fifi did not show signs of sickness but triggered her immune system to fight off the virus protein by generating nanobodies against it.
The researchers took blood samples from the llama and were able to purify four nanobodies capable of binding to the virus. Later the nanobodies were combined into chains of three to increase their ability to bind to the virus. Finally, they were produced in cells in the laboratory.
According to the study, three nanobody chains were able to neutralize both the original variants of the Covid-19 virus and the alpha variant. While the fourth nanobody chain was able to neutralize the beta variant.
In trials conducted on Hamsters infected with a virus, was given one of the nanobody chains showed a marked reduction in disease. The hamsters also had a lower viral load in their lungs and airways after seven days than untreated animals.
The results are the first step towards developing a new treatment against Covid 19, according to the researchers. It can prove to be invaluable as the pandemic continues.
“Having medications that can treat the virus is still going to be very important, particularly as not all of the world is being vaccinated at the same speed and there remains a risk of new variants capable of bypassing vaccine immunity emerging.”, said Professor James Naismith, director of the Rosalind Franklin Institute. He led the research and included scientists at the University of Liverpool, University of Oxford, and Public Health England. They are now hopeful for obtaining funding to prepare for clinical studies in humans.
The research has been funded by the UK Research and Innovation’s Medical Research Council and the Engineering and Physical Sciences Research Council, The EPA Cephalosporin Fund, and Wellcome. They also believe the nanobody technology they have developed could form a so-called platform technology that can be rapidly adapted to fight other diseases. The findings of the research are published in the journal Nature Communication.