Updated: June 19, 2022 23:32 IST
Washington [US], Jun 19 (ANI): Researchers have reported simple and accurate glucose meter-based tests containing novel fusion proteins. They say consumers will one day be able to use this test to check their SARS-CoV-2 antibody levels.
The findings were published in the Journal of the American Chemical Society (ACS).
Vaccines against SARS-CoV-2 and infection with the virus itself may protect against future infections for a while, but it’s unclear exactly how long that protection lasts. A good indication of immune protection is a person’s level of SARS-CoV-2 antibodies, but the gold standard measurement — the enzyme-linked immunosorbent assay (ELISA) — requires expensive equipment and specialized technicians.
Enter glucose meters, which are readily available, easy to use and integrate with remote clinical services. Researchers have adapted these devices to detect other target molecules, linking detection to glucose production.
For example, if a detection antibody in the test binds to an antibody in a patient’s blood, a reaction occurs that produces glucose — something the device detects very well. Invertase is an attractive enzyme for this type of analysis because it converts sucrose to glucose, but it is difficult to attach the enzyme to detection antibodies by chemical approaches.
So, Netzahualcoyotl Arroyo-Curras, Jamie B. Spangler and colleagues wanted to see whether producing a fusion protein consisting of both invertase and a detection antibody would work in an assay that could read SARS-CoV-2 antibody levels with a glucose meter.
The researchers designed and produced a new fusion protein that contains both invertase and a mouse antibody that binds to human immunoglobulin (IgG) antibodies. They showed that the fusion protein was bound to human IgGs and successfully produced glucose from sucrose. Next, the team made test strips with the SARS-CoV-2 spike protein on them. When immersed in COVID-19 patient samples, the patients’ SARS-CoV-2 antibodies bound to the spike protein.
Adding the invertase/IgG fusion protein and then sucrose resulted in the production of glucose, which could be detected with a glucose meter. They validated the test by running the analysis with glucose meters on different patient samples and found that the new test worked just as well as four different ELISAs. The researchers say the method could also be adapted to test for SARS-CoV-2 variants and other infectious diseases.
The authors acknowledge funding from the Johns Hopkins University School of Medicine, the Emerson Collective Cancer Research Fund, and the National Institutes of Health.
The American Chemical Society (ACS) is a non-profit organization chartered by the United States Congress. ACS’s mission is to advance the wider chemical company and its practitioners for the benefit of the Earth and all of its people.
The Society is a global leader in promoting excellence in science education and providing access to chemistry-related information and research through its multiple research solutions, peer-reviewed journals, scientific conferences, eBooks, and the weekly news magazine Chemical & Engineering News.
ACS journals are among the most cited, most trusted, and most widely read journals in the scientific literature; However, ACS does not conduct chemical research itself. As a leader in scientific information solutions, the CAS division partners with global innovators to accelerate breakthroughs by collecting, connecting and analyzing the world’s scientific knowledge. ACS’s corporate headquarters are located in Washington, DC and Columbus, Ohio. (ANI)