As the global public health sector searches for an effective treatment for COVID-19, some are looking to veterinary research for potential solutions, even though the SARS-CoV-2 coronavirus that causes COVID-19 is not related to any known coronavirus affecting livestock or domesticated animals.
For example, a team of researchers from The University of Texas at Austin (UT-Austin), the National Institutes of Health and Ghent University in Belgium reported their findings about a potential coronavirus treatment involving llamas in the journal Cell. The paper is currently available online as a "pre-proof," meaning it has been peer reviewed but is undergoing final formatting.
The researchers linked two copies of a special kind of antibody produced by llamas to create a new antibody that binds tightly to a key protein on the coronavirus that causes COVID-19, according to an announcement from UT-Austin. This protein, called the spike protein, allows the virus to break into host cells. Initial tests indicate that the antibody blocks viruses that display this spike protein from infecting cells in culture.
"This is one of the first antibodies known to neutralize SARS-CoV-2," said Jason McLellan, associate professor of molecular biosciences at UT-Austin and co-senior author.
The team is now preparing to conduct preclinical studies in laboratory animals with the hopes of next testing the treatment in people. The goal is to develop a treatment that would help people soon after infection with the virus, UT-Austin said.
"Vaccines have to be given a month or two before infection to provide protection," McLellan said. "With antibody therapies, you're directly giving somebody the protective antibodies, so immediately after treatment, they should be protected. The antibodies could also be used to treat somebody who is already sick to lessen the severity of the disease."
According to the researchers, when llamas' immune systems detect foreign invaders such as bacteria and viruses, these animals (and other camelids such as alpacas) produce two types of antibodies: one that is similar to human antibodies and another that's only about a quarter of the size. These smaller ones, called single-domain antibodies, or nanobodies, can be nebulized and used in an inhaler.
"That makes them potentially really interesting as a drug for a respiratory pathogen because you're delivering it right to the site of infection," said Daniel Wrapp, a graduate student in McLellan's lab and co-first author of the paper.
The final paper will appear on May 5.
Meanwhile, Mohit Verma, assistant professor in the Purdue University department of agricultural and biological engineering, is focusing his research on developing biosensors to monitor infectious diseases in cattle.
Specifically, he studies how to diagnose bovine respiratory disease (BRD), the most common bovine disease in beef cattle in the world. Detection of the disease can be difficult and costly. Verma’s lab develops methods for testing that are accurate, safe and less expensive for farmers and veterinarians, according to a post from Purdue.
“The technique we use is based on the identification of nucleic acids specific to that virus,” Verma said. “The test will show us what pathogen is causing the infection. This helps determine which antibiotic to prescribe.”
The tests are small sensors, cheap and easy to produce that provide test results in a matter of minutes.
“That’s exactly what is needed right now for COVID-19 testing,” Verma said. “So, back in February, we began looking at ways to adapt the biosensor used for BRD to a cheap, reliable test for COVID-19 and other SARS diseases.”
The tests have performed well in the lab setting, and Verma said he is working with external partners to fast-track the approval of the device when the time is appropriate, Purdue said, noting that several challenges remain, specifically logistics.
The project is being accelerated, attempting to accomplish a goal in months that would typically take years; there are technical challenges in the lab, and Verma faces challenges with purchasing, personnel and facilities. His target is for the device to be submitted to the Food & Drug Administration for emergency use within three months.
Long term, Verma said he hopes this same kind of technology can be used for other kinds of viruses, including influenza. Ideally, one device could detect multiple targets, which would improve diagnostic accuracy, cut down on health care cost and save time for health care professionals.
“This is a great example of how the technology developed in agriculture can have implications far beyond that sphere,” Verma said.