SARS-CoV-2 Serology and PCR Testing
Accurate molecular tests for active SARS-CoV-2 infection and subsequent serological tests for the presence of anti-viral antibodies are key tools for identifying affected individuals and for understanding the immune response in those who have recovered. Availability of specific and sensitive tests of both types (for diagnosis and antibody testing) is critical to the success of efforts to fight the COVID-19 pandemic.
Research, development and manufacturing of molecular tests and serological assays is an urgent need that is a focus of many laboratories worldwide. Promega provides products and custom services to labs designing, performing and scaling up PCR-based molecular tests, and to support labs performing serological assays and researching new serological testing methods.
“Many companies and research teams around the world are working to develop serological assays that can help us in the fight against COVID-19. Any test to be widely deployed must prove both sensitivity and specificity and must have the ability to determine if the antibody level is actually protective for the patient.”
- Ash Anderson, Promega Chief Medical Officer
PCR-Based SARS-CoV-2 Testing Methods
RT-qPCR based assays designed to amplify SARS-CoV-2-specific sequences are the primary method currently used for detection of active infections. Tests are available targeting various unique SARS-CoV-2 sequences in the N, E, S and RdRp sequences (3,10). RT-qPCR tests that use two or more targets are likely to have higher specificity.
The World Health Organization (WHO) has published summary information for a few protocols including the United States recommended protocol (11). The CDC recommends using the CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel for primary diagnosis, which includes primers and probes for different regions of the nucleocapsid (N) gene plus an additional primer/probe set for detection of RNase P (RP) gene in control/clinical samples (12,13).
Other organizations have released their own kits. On February 25 2020, Promega was recognized by Co-Diagnostics, Inc. for support in manufacturing the new Logix Smart™ COVID-19 Test, which received CE mark approval and is available in Europe as an in vitro diagnostic.
“Promega is proud to support the CDC’s rapid response efforts and COVID-19 testing labs with approved amplification technology"
- Zhou, P. et al. (2020) A pneumonia outbreak associated with a new coronavirus of probable bat origin. Nature 579, 270-3.
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- Li, X. et al. (2020) Molecular immune pathogenesis and diagnosis of COVID-19. J. Pharm. Anal.10, Issue 2, (April) 102-8.
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- Richardson, P. et al. (2020) Baricitinib as potential treatment for 2019-nCoV acute respiratory disease. Lancet 395, e30–e31 (2020).
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- Wu, R., et al. (2020) An Update on Current Therapeutic Drugs Treating COVID-19. Curr Pharmacol. Rep. May 11; 1‐15. doi:10.1007/s40495-020-00216-7.
- Corman, V.M. et al. (2020) Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR. Euro Surveill., 25, 10.2807/1560-7917.ES.2020.25.3.2000045.
- World Heath Organization PCR protocol - World Health Organization. Accessed on May 13, 2020. https://www.who.int/docs/default-source/coronaviruse/whoinhouseassays.pdf?sfvrsn=de3a76aa_2.
CDC 2019-Novel Coronavirus (2019-nCoV) Real-Time RT-PCR Diagnostic Panel. Accessed May 13, 2020. https://www.fda.gov/media/134922/download.
Coronavirus Disease 2019 (COVID-19): FAQ for laboratories Accessed May 13, 2020. https://www.cdc.gov/coronavirus/2019-ncov/lab/testing-laboratories.html.
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- Ahmed, S.F. et al. (2020) Preliminary Identification of Potential Vaccine Targets for the COVID-19 Coronavirus (SARS-CoV-2) Based on SARS-CoV Immunological Studies. Viruses 12(3), 254.
- Tay, M.Z., et al. (2020) The trinity of COVID-19: immunity, inflammation and intervention. Nat Rev Immunol. https://doi.org/10.1038/s41577-020-0311-8.
- Serology-based tests for COVID-19. Johns Hopkins University Center for Health Security.