Peter the Great St. Petersburg Polytechnic University (SPbPU) have created a diagnostic platform based on CRISPR-Cas technology that quickly and reliably detects a wide range of infectious diseases. This was reported to socialbites.ca in the Priority-2030 program of the Ministry of Science and Higher Education of the Russian Federation.
CRISPR-Cas is the natural defense system of bacteria against viruses. Bacteria have developed many protective mechanisms during the struggle for life and have stored DNA fragments of viruses in their genomes. Today, CRISPR-Cas technologies are used in gene therapy to edit “damaged” genes. SPbPU scientists decided to use this system to create tests to identify pathogens in the human body.
The diagnostic platform uses fluorescent probes, organic compounds that give off a fluorescent signal (color staining) when the Cas12 protein specifically recognizes the genetic material of the virus in the sample. When a virus enters a cell, it pairs its DNA with all the other virus DNA stored in it. And if the cell recognizes a familiar virus, the Cas protein cuts its DNA so that infection does not occur.
The method can be configured to detect any virus or bacteria such as influenza, measles, smallpox, chickenpox, typhoid fever, hepatitis, diphtheria, SARS-CoV-2, and others.
Programming the system is not quick, but once the process is complete it will take 10-20 minutes to identify the pathogen. Scientists say this is longer than rapid tests, but much faster and much more accurate than PCR tests. At the same time, the method does not require special equipment and highly qualified personnel – a sample is added to the reagent mixture and infection is detected in a test tube.
“Most of the pathway diagnostic methods used today require specialized equipment and also a relatively long time to obtain results. In addition, test results can be false positive or false negative. The frequency of false negative results is between 2% and 58% depending on the test method and conditions. The use of CRISPR-Cas systems increases the precision of diagnosis, which can significantly increase the reliability of the result, Natalia Morozova, project manager and researcher at the Molecular Microbiology Laboratory, told socialbites.ca.