The current reference method for detecting the SARS-CoV-2 virus in an organism is polymerase chain reaction (PCR) testing, which searches for a virus-specific gene sequence after nasal swabbing. This approach enables a large number of analyses, but still depends on genetic mutations that may appear in the virus and is time-consuming to implement.
The CEA-Joliot team has recently demonstrated the possibility of an alternative virus detection strategy as a supplement to current diagnostic methods. It successfully used the shotgun proteomics[1] to detect and identify a shortlist of 14 CoV-2-SARS signature peptides in a model of viral proteins expressed in cultured cells.
In the present study, researchers analyzed nasal swab samples from patients in remission at Nîmes University Hospital by tandem mass spectrometry and were able to identify two peptides of the SARS-CoV-2 nucleoprotein in only three minutes of acquisition and without any specific reagent.
Faster, more accurate, and not subject to the genetic variations of SARS-CoV-2, the mass spectrometry method used here thus provides a proof of concept to supplement the reference PCR method, which remains indispensable at this stage. To become more widely implemented, the proposed approach will require smaller instruments and optimization of the process.
[1] Shotgun proteomics refers to the characterization of protein fragments for identification in complex mixtures using a combination of high performance liquid chromatography and tandem mass spectrometry.