Llama antibody engineered to block coronavirus
by Sharon Reyonlds/NIH Research Matters
At a Glance
- Based on antibodies isolated from llamas, researchers engineered an antibody that prevented SARS-CoV-2, the virus that causes COVID-19, from entering cells in laboratory experiments.
- Follow-up work is being planned to test the antibody in animal models of the disease.
Animals produce antibodies much like those made by the human immune system. But some animals, such as llamas, also produce another type of antibody that’s only about a quarter of the size of a typical human antibody. Such “single-domain” antibodies, or nanobodies, have several features that make them of interest as potential therapeutics.
Nanobodies are very stable, so they could potentially be stored for a long time after production. They can also be delivered by an inhaler directly to the lungs, which makes them particularly promising for respiratory infections such as COVID-19.
The World Health Organization declared COVID-19 an international pandemic on March 11, 2020. To date, it has infected more than 4 million people worldwide and killed over a quarter million. Researchers are rushing to develop vaccines. In the meantime, effective treatments are urgently needed.
Researchers led by Daniel Wrapp and Dr. Jason McLellan from the University of Texas, in collaboration with a Belgian research team, had developed nanobodies from llamas for research into Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). Both these diseases are caused by coronaviruses related to SARS-CoV-2.
References: Structural Basis for Potent Neutralization of Betacoronaviruses by Single-Domain Camelid Antibodies. Wrapp D, De Vlieger D, Corbett KS, Torres GM, Wang N, Van Breedam W, Roose K, van Schie L; VIB-CMB COVID-19 Response Team, Hoffmann M, Pöhlmann S, Graham BS, Callewaert N, Schepens B, Saelens X, McLellan JS. Cell. 2020 Apr 29. pii: S0092-8674(20)30494-3. doi: 10.1016/j.cell.2020.04.031. [Epub ahead of print] PMID: 32375025.
Funding: NIH’s National Institute of Allergy and Infectious Disease (NIAID); Vlaams Instituut voor Biotechnologie; Ghent University; Research Foundation – Flanders; Agentschap Innoveren & Ondernemen; RAPID Consortium.