Singapore and the United States researchers have developed an express test that allows you to determine the blood level of antibodies that neutralize new variants of Coronavirus SARS-COV-2. It requires only a drop of blood from the finger, and the process itself takes only ten minutes. Description of development and its action is stated by scientists in the Communications MEDICINE journal and in Preprint on MedRxiv.
Now the level of neutralizing antibodies to SARS-COV-2 in human blood is still determined in specialized centers using tests for the virus neutralization reaction, which require high biosafety levels and occupy from two to four days. Researchers from Nanyang Technological University, National University of Singapore and Massachusetts Institute of Technology created a new express test for virus neutralization. It is a paper strip that is impregnated with a solution with receptor-binding domains of the Coronavirus S-protein. They cause a patient’s blood sample and a glowing dye, which includes the ACE2 receptor molecules, the “gate” in the cell for SARS-COV-2.
The blood antibodies will prevent the compound of the S-protein with fragments of the coronavirus shells – and there is less sneakened viral particles on the strip. Researchers checked the accuracy of their test on the blood samples of several dozen patients vaccinated by Pfizer with respect to Wuhan, alpha, beta, gamma and delta variants of coronavirus. The accuracy of the test was 93 percent – which is higher than in laboratory tests. In addition, testing confirmed a significant decrease in the titer of antibodies in the blood of people three months after vaccination.