Related Experiment Video
Updated: Dec 18, 2025
08:48
Dynamic Monitoring of Seroconversion using a Multianalyte Immunobead Assay for Covid-19
Published on: February 16, 2022
3.2K
Serological differentiation between COVID-19 and SARS infections
Wan Ni Chia1, Chee Wah Tan1, Randy Foo1
1Programme in Emerging Infectious Diseases, Duke-NUS Medical School, Singapore, Singapore.
Emerging Microbes & Infections
|June 13, 2020
Summary
Serological tests for COVID-19 are crucial but face cross-reactivity challenges with other coronaviruses. Using spike protein regions like S1 or RBD offers better specificity than nucleocapsid protein, with capture ELISA performing best.
Area of Science:
- Immunology
- Virology
- Diagnostic Test Development
Background:
- The COVID-19 pandemic necessitates diverse diagnostic tools beyond PCR, including serological assays for tracing and immunity assessment.
- Antibody tests for SARS-CoV-2 face significant cross-reactivity issues due to genetic similarities with other human coronaviruses, notably SARS-CoV.
- Understanding cross-reactivity is vital for accurate COVID-19 serological testing and assessing long-term immunity.
Purpose of the Study:
- To develop and evaluate four distinct serological tests for COVID-19.
- To comprehensively assess cross-reactivity between SARS-CoV-2 and SARS-CoV patient sera.
- To identify optimal viral antigens and assay platforms for specific and sensitive COVID-19 antibody detection.
Main Methods:
- Development and comparative performance analysis of four different serological assays.
- Utilized nucleocapsid (N) protein and spike (S) protein regions (S1, RBD) of SARS-CoV-2 and SARS-CoV for antigen targets.
- Employed capture ELISA and other platforms to analyze patient sera from COVID-19 and SARS infections.
Main Results:
- Significant cross-reactivity was observed when using the N protein of either SARS-CoV-2 or SARS-CoV.
- Employing S1 or RBD regions of the spike protein demonstrated improved specificity, reducing cross-reactivity.
- Capture ELISA emerged as the superior platform among those tested for antibody detection.
- SARS survivors exhibited sustained antibody levels 17 years post-infection, with anti-RBD antibodies waning slower than anti-N antibodies.
Conclusions:
- Spike protein regions (S1/RBD) are more specific targets than N protein for COVID-19 antibody tests, mitigating cross-reactivity.
- Capture ELISA offers enhanced performance for serological diagnosis of COVID-19.
- Long-term antibody persistence, particularly for RBD antibodies crucial for immunity, highlights the need for specific and durable serological markers.
