PJSC “SPC “Diaproph-Med” in accordance with the requirements of the international quality management standard ISO13485, conducted a comparative study of amino acid sequences of recombinant antigens SARS-CoV-2 of its own production and proteins of Indian isolate SARS-CoV-2 "DELTA" (B.1.617.2) according to the European Center for Disease Prevention and Control (ECDC) risk assessment report 1.
The genome of the Indian strain DELTA SARS-CoV-2 does not contain large deletions in diagnostically important sites, but has a large number of point substitutions (mutations) in the gene responsible for the synthesis of surface protein SPIKE.
Thus, the nucleocapsid protein (NP) SARS-CoV-2 of own production and the nucleocapsid protein (NP) SARS-CoV-2 "DELTA" B.1.617.2 variant GenBank accession No. QWP92477.1 has a match of 98.8%.
Surface protein (SPIKE) SARS-CoV-2 of own production and Surface protein (SPIKE) SARS-CoV-2 SPIKE "DELTA" B.1.617.2 variant GenBank accession No. QWP92470.1 has a match of 99.3%.
Membrane protein (M) SARS-CoV-2 of own production and Membrane protein (M) SARS-CoV-2 «DELTA» B.1.617.2 variant GenBank accession No. QUX81285.1 has a match of 99.1%.
Shell protein (E) SARS-CoV-2 of own production and Shell protein (E) SARS-CoV-2 "DELTA" B.1.617.2 variant GenBank accession No. QUX81284.1 has a match of 100%.
The comparison shows the absence of a significant threat of reducing the diagnostic sensitivity of test systems manufactured by PJSC “SPC “Diaproph-Med” for the detection of coronavirus disease due to mutations in variants of the strain "DELTA" (B.1.617.2) SARSCoV-2.
Introduction of multi-target test systems such as DIA®-SARS-CoV-2-NP-S-IgM for qualitative detection of IgM antibodies to nucleoprotein (nucleocapsid antigen, NP) and surface (spike-protein, S) antigens of coronavirus SARS-CoV -2, DIA®-SARS-CoV-2-different for differential detection of antibodies to all structural proteins of the virus - NP, S, M and E provides a tool for diagnostic laboratories for in-depth research in the face of new mutations in the virus.
Specialists of PJSC “SPC “Diaproph-Med” are constantly monitoring SARS-CoV-2 mutations and the emergence of new variants of the virus in order to improve the design of test systems to ensure maximum sensitivity and specificity.