Antibodies taken from llamas and administered via an asthma-style inhaler could be used to save patients with Covid-19.
Researchers from the National Institute of Health (NIH) have isolated a set of promising, tiny antibodies, or ‘nanobodies’, that were produced by a llama named Cormac.
The powerful antibodies have been found to be more effective at fighting coronavirus than human equivalents.
More stable and less expensive to produce
The antibodies are known as ‘nanobodies’ due to their small size, and early indicators have shown they are effective in aerosol form. They could be given to humans as a nasal spray or an asthma-styled inhaler.
A nanobody is a special type of antibody that is naturally produced by the immune systems of camelids - a group of animals that includes camels, llamas and alpacas. On average, the proteins are about a tenth the weight of most human antibodies, and are more stable, less expensive to produce, and easier to engineer than typical antibodies.
Professor David Brody, who co led the study, “We hope these anti-Covid-19 nanobodies may be highly effective and versatile in combating the coronavirus pandemic.”
In July, a study revealed that llama nanobodies were able to block the spike protein of the Sars-Cov-2 virus from entering human cells.
The study published by Rosalind Franklin Institute, Oxford University, Diamond Light Source and Public Health England, engineered the new nanobodies using a collection of antibodies taken from llama blood cells.
Cormac the llama
Researchers from a brain imaging lab at the NIHs National Institute of Neurological Disorders and Stroke, turned to Cormac the llama for the nanobodies used in the study.
Scientists injected the llama with a ‘pseudovirus’ that worked to kickstart his immune system and the production of antibodies. Cormac was immunised five times over 28 days with a purified version of the Sars-CoV-2 spike protein.
After testing hundreds of nanobodies, the researchers found that Cormac produced 13 nanobodies that might be strong candidates.
The researchers showed that the nanobody was equally effective in preventing the infections in petri dishes when it was sprayed through the kind of nebulizer, or inhaler, often used to help treat patients with asthma.
Professor Brody said, “One of the exciting things about nanobodies is that, unlike most regular antibodies, they can be aerosolised and inhaled to coat the lungs and airways.”
The team has applied for a patent on the NIH-CoVnB-112 nanobody.