Gates Funding Home-Based Crispr Covid-19 Diagnostic

(LJNovaScotia, Pixabay)

16 Dec. 2020. A medical device developer is receiving a Gates Foundation grant for a simple test to detect Covid-19 infections, done completely at home. The Bill and Melinda Gates Foundation awarded Sherlock Biosciences, in Cambridge, Massachusetts $5 million to adapt its molecular diagnostics technology to a home-based diagnostic for SARS-CoV-2 viruses responsible for Covid-19 infections.

A key requirement for gaining control of the Covid-19 pandemic in the U.S. and elsewhere is rapid, widely-available testing for infections that can alert individuals and their close contacts for the need to isolate and watch for symptoms. Most Covid-19 diagnostics today use the so-called gold standard reverse transcription-polymerase chain reaction, or RT-PCR, testing to identify SARS-CoV-2 viral genetic material in nasal swabs or other specimen samples. For the vast majority of these tests, samples are sent to remote labs for analysis, causing long backlogs and delays stretching into several days to get results.

Sherlock Biosciences develops diagnostic tests using Crispr, short for clustered regularly interspaced short palindromic repeats. Crispr is a genome-editing process based on bacterial defense mechanisms that use RNA to identify and monitor precise locations in DNA. Sherlock, short for specific high-sensitivity enzymatic reporter unlocking, employs Crispr to edit RNA rather than DNA.

The Sherlock technology, first developed at research labs affiliated with Harvard University and MIT, uses Crispr editing enzymes that seek out specific genetic sequences in a specimen sample, and if detected in the sample, bind to and cut the RNA in nearby locations. Sherlock adds a reporter sequence to the RNA, a specific piece of synthetic RNA, which also gets cut by the editing enzyme, releasing a signal identifying the presence of the original target sequence.

When coupled with a companion technique called Inspectr, short for internal splint-pairing expression cassette translation reaction, reporter sequence signals are converted into a bioluminescent visual display that can appear on an everyday material like paper and at room temperature. Sherlock says the signals can also be captured electronically for display on smartphones or other mobile devices.

As reported by Science & Enterprise, Sherlock Biosciences developed a paper-strip testing system to quickly detect SARS-CoV-2 viruses, which in May 2020 received an emergency authorization from the Food and Drug Administration for use in lab settings. The Gates Foundation award funds further advances in the technology for use in tests sold over-the-counter and done at home with accuracy and reliability similar to RT-PCR tests.

“In addition to advancing our Inspectr platform development to be as sensitive as gold-standard PCR tests,” says Sherlock’s chief technology officer William Blake in a company statement, “the funding will support our development of an over-the-counter disposable product, similar to an at-home pregnancy test, that can be used to detect SARS-CoV-2, the virus that causes Covid-19. Pending approval, we are on track to launch this product in mid-2021.”

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• Covid-19 Saliva Test Earns FDA Emergency Clearance
• Electric Crispr Chip Quickly Detects Covid-19 Virus

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