What if there was a way to accurately test people for COVID-19 as quickly and efficiently as the coronavirus can spread from person to person? It sounds like a pipe dream, but a resilient group of scientists from The University of California, Santa Barbara have developed a new CRISPR coronavirus test that is fast, cost-efficient, and easy to use at medical sites.
Countries and communities all over the world continue to report a dearth of available coronavirus tests. But, why is that? Right now, the most widely used form of coronavirus detection is PCR (polymerase chain reaction) testing. These tests, however, are dependent on reagents (a chemical substance or mixture that must be added to the test to produce a result), and reagents are in short supply.
“They are depleted around the world,” says UC Santa Barbara molecular biologist Max Wilson, regarding reagents. Wilson and his colleagues just donated over 600 reagents to Santa Barbara’s Cottage Health System to help out their local community.
The beauty of this newly developed CRISPR-based test is that it doesn’t require any reagents to produce an accurate result. It can also be used in the field by health professionals, something that can’t be done with PCR tests. How is this possible? The research team programmed a new bacterial protein (Cas13) capable of identifying the coronavirus using CRISPR gene-editing technology. When the protein comes into contact with the virus it starts “chewing” on its RNA, producing a fluorescent glow that can quickly let doctors know of a positive result.
“Our little wells just light up if the virus is present when we mix all these things together,” Wilson explains.
The new test, called CREST (Cas13-based, Rugged, Equitable, Scalable Testing), is just as accurate as a PCR test, according to its developers. Moreover, it isn’t all that difficult to specify Cas13 proteins for this purpose. The research team already has hundreds of thousands ready to go.
“We’ve scaled up massively,” Wilson says in a press release. “For example, we’ve purified enough of the protein for our CRISPR-based assay to do 500,000 tests in one go.”
Of course, while all of this ultra promising, this test like so many others faces the challenge of FDA approval and CDC recognition.
“Right now we cannot distribute it for diagnostic purposes,” Wilson explains. “We are evaluating the potential need and hurdles.”
“It appears that the UCSB team has produced what Dr. Deborah Birx asked for earlier this week — a testing breakthrough,” says Joseph Incandela, UC Santa Barbara’s vice chancellor for research. “They did it while shifting to teaching remotely, taking care of kids at home, and all the other challenges of the situation we’re in. This is phenomenal, and I hope that we can now navigate the path of FDA approval quickly, for everyone’s sake.”
It’s quite remarkable that the team behind this test (Wilson, as well as his colleagues Kenneth S. Kosik, Diego Acosta-Alvear, and Carolina Arias) were able to produce such innovations while cut off from their equipment on campus.
“I’ve long since mourned that loss,” Wilson concludes. “But I don’t even worry about it because this is just what we have to do.”
The full study can be found here, published in bioRxiv.
John Anderer is a frequent Ladders contributor.