New biosensors quickly detect coronavirus proteins and antibodies

Scientists have created a new way to detect the proteins that make up the pandemic coronavirus, as well as the antibodies against it. They designed protein-based biosensors that glow when mixed with specific virus components or COVID-19 antibodies. This discovery could allow for faster and more comprehensive testing in the near future. The search appears in Nature.

To diagnose coronavirus infection today, most medical laboratories rely on a technique called RT-PCR, which amplifies the virus’s genetic material so it can be seen. This technique requires specialized equipment and staff. It also consumes laboratory supplies that are now in high demand around the world. Supply chain deficiencies have slowed the results of COVID-19 tests in the United States and beyond.

In an effort to directly detect coronavirus in patient samples without the need for genetic amplification, a team of researchers led by David Baker, professor of biochemistry and director of the Institute for Protein Design at UW Medicine, used computers to design new biosensors. These protein-based devices recognize specific molecules on the surface of the virus, attach to them and emit light through a biochemical reaction.

The antibody test can reveal whether a person has had COVID-19 in the past. It is being used to track the spread of the pandemic, but it also requires complex laboratory materials and equipment.

The same team of UW researchers has also created biosensors that glow when mixed with COVID-19 antibodies. They showed that these sensors do not react to other antibodies that may also be in the blood, including those that target other viruses. This sensitivity is important to avoid false positive test results.

“We showed in the lab that these new sensors can readily detect virus proteins or antibodies in simulated nasal fluid or donated serum, said Baker.” Our next goal is to ensure that they can be used reliably in a diagnostic environment. This work illustrates the power of protein design again to create molecular devices from scratch with new and useful functions. “

In addition to COVID-19, the team also showed that similar biosensors could be designed to detect medically relevant human proteins, such as Her2 (a biomarker and therapy target for some forms of breast cancer) and Bcl-2 (which has clinical significance in lymphoma and some other cancers), as well as a bacterial toxin and antibodies that target the Hepatitis B virus.