The study by Yunguang Sun and colleagues presents a robust protocol for detecting SARS-CoV-2 proteins in formalin-fixed, paraffin-embedded (FFPE) tissues. The research aims to enhance the detection of SARS-CoV-2 viral proteins, aiding in the study of COVID-19 pathogenesis and pathology across various tissues.
The protocol involves the use of commercially available affinity-purified polyclonal antibodies targeting the nucleocapsid and spike proteins of SARS-CoV-2. These antibodies provide sensitive and specific detection of the virus in FFPE tissue samples from COVID-19 patients. The study validated two immunohistochemistry (IHC) protocols by demonstrating matched detection patterns of nucleocapsid and spike proteins in virus-infected cells within autopsy lung tissue from COVID-19 deceased patients. The nucleocapsid protein sequence’s conservation across all known SARS-CoV-2 strains ensures the protocol’s applicability to all common variants.
A significant finding is the strong correlation between nucleocapsid protein levels in lung tissues, as detected by IHC, and viral RNA levels, as measured by quantitative RT-PCR. This correlation underscores the protocol’s accuracy and reliability for assessing viral load. The research also highlights that the IHC protocols are expected to be transferable to other species, including experimental animal models and potential viral reservoirs.
The development of these protocols addresses the need for sensitive tools to study virus distribution and associated tissue changes, contributing to the broader understanding of COVID-19’s impact on various organs and aiding in the development of effective treatments.
Key Takeaways:
- High Sensitivity & Specificity: The protocol effectively detects SARS-CoV-2 nucleocapsid and spike proteins in FFPE tissues, offering a reliable method for studying viral distribution and load in COVID-19 patients
- Broad Applicability: Due to the conservation of the nucleocapsid protein sequence, the protocol is applicable to all common SARS-CoV-2 variants, ensuring its utility in diverse clinical and research settings
- Correlation with RNA Levels: The strong correlation between IHC-detected nucleocapsid protein levels and viral RNA levels measured by RT-PCR validates the protocol’s accuracy for assessing viral load in tissue samples
These findings provide a valuable tool for researchers and clinicians to investigate SARS-CoV-2’s tissue tropism and pathology, enhancing the understanding and management of COVID-19.
ProSci has generated several antibody reagents for SARS-CoV-2 research. Two of these antibodies were used in the research summarised (1, 2). ProSci has over 20 years of experience generating antibodies against various targets. The next time you are in the market for commercial or custom antibodies, let ProSci help further your research efforts.
References
- Anti-SARS-CoV-2 nucleocapsid protein antibody (affinity-purified rabbit IgG; ProSci, Poway, CA, USA; Cat. No. 9099).
- Anti-SARS-CoV-2 spike S1 glycoprotein antibody (affinity-purified rabbit IgG (ProSci; Cat. No. 9083).
Originally posted on: Sensitive and Specific Immunohistochemistry Protocol for Nucleocapsid Protein from All Common SARS-CoV-2 Virus Strains in Formalin-Fixed, Paraffin Embedded Tissues – ProSci (prosci-services.com)
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