Could Llamas be the Answer to Neutralizing COVID-19?
The relationship between llamas and humans spans centuries. Andean communities have long relied on these creatures for clothing, transportation, and even fuel. Peaceful in nature, llamas have served as therapy animals to alleviate depression and anxiety in humans. More recently, however, llamas have been heralded for their potential in another therapeutic area -- infectious diseases. Newly-published research indicates their antibodies can offer a defense to neutralize COVID-19, the respiratory illness that has infected millions globally, brought economies to a halt, and where a treatment is desperately needed.
The secret is in their ‘single-domain’ nanobodies, a tiny class of antibodies distinctly produced in camelids -- the animal family encompassing alpacas, llamas, and camels. About a quarter of the size of the antibodies that humans produce, nanobodies have the ability to stave off respiratory viruses, in addition to influenza and HIV. They are also stable in nature and can be stored for a long time after they are produced.
The figurehead of this research is Winter, a four-year-old llama living on a farm in the Belgian countryside. In 2016, scientists--funded by the National Institutes of Health (NIH), University of Texas at Austin and Ghent University in Belgium--began conducting antibody research against known coronaviruses Middle East Respiratory Syndrome (MERS) and Severe Acute Respiratory Syndrome (SARS). Over the course of six weeks, they injected her with spike proteins found on these viruses’ surfaces, which break into host cells and cause infection.
* They subsequently collected blood samples, isolating and analyzing the nanobody structures she developed that bonded to the spike proteins. Through binding to these spike proteins, these antibodies cannot infect host cells.
Researchers then manipulated the nanobodies to stick to the virus by fusing the copies together, and have reproduced these sequences in a lab. The findings, the researchers deduced, may effectively block the novel coronavirus in humans. This work was published last month in the scientific journal, Cell.
Many are curious to understand how antibody treatments differ from a vaccine. With the latter, you’re applying something that mimics the virus, usually a month before its potential onset. In the case of an antibody treatment, you’re directly administering the virus into your bloodstream, providing numerous benefits at a rapid rate. This could be especially useful for someone who is at risk, experiencing symptoms, or has become infected -- to quickly reduce the disease burden and fight off the virus. What’s more, this can be directly administered through an inhaler, even more impactful in warding off a respiratory disease like COVID-19. This approach of providing antibodies may also be more beneficial to the elderly than a vaccine, who normally have issues in raising an active immune response.
Currently, this project is in a pre-clinical trial phase, where antibodies are injected in hamsters. Upon successful results, the next step of the trial will include testing on non-human primates, and then onto phase one testing in humans. This entire process is estimated to take about a year. Given the timeline in which the scientists began four years ago, these encouraging results underscore the importance of conducting basic research and the overall trust in the scientific community.
Author: Kristen Tadrous
Editors: Hailey Matarese and Alondra Magaña
*For those of you wondering, Winter was not harmed. Researchers injected a small, non-infectious portion of the virus to elicit these antibodies. Once they had sequences, they could produce nanobodies in the lab to forego continuously drawing blood. I call that a win.
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References:
Anon, 2020. COVID-19 Researchers Study Llama's Special Antibodies. Morning Edition. Available at: https://www.npr.org/2020/05/19/858499008/covid-19-researchers-study-llamas-special-antibodies [Accessed June 4, 2020].
Cantor, M., 2020. Llama antibodies could help fight coronavirus, study finds. The Guardian. Available at: https://www.theguardian.com/world/2020/may/16/llama-coronavirus-antibodies-study-benefits [Accessed June 4, 2020].
Kramer, J., 2020. Hoping Llamas Will Become Coronavirus Heroes. The New York Times. Available at: https://www.nytimes.com/2020/05/06/science/llama-coronavirus-antibodies.html [Accessed June 4, 2020].
Reynolds, S., 2020. Llama antibody engineered to block coronavirus. National Institutes of Health. Available at: https://www.nih.gov/news-events/nih-research-matters/llama-antibody-engineered-block-coronavirus [Accessed June 4, 2020].
Robinson, A., 2020. Meet Winter, the Llama Who Might Just Save Us All From COVID-19. Modern Farmer. Available at: https://modernfarmer.com/2020/05/meet-winter-the-llama-who-might-just-save-us-all-from-covid-19 [Accessed June 4, 2020].
Rosen, S.G. & Wertlieb, M., 2020. Llama Antibodies Neutralize Virus That Causes COVID-19, New Research Shows. CommonHealth. Available at: https://www.wbur.org/commonhealth/2020/05/16/llama-antibodies-can-neutralize-virus [Accessed June 4, 2020].
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