Fusing Peptide Epitopes for Advanced Multiplex Serological Testing for SARS-CoV-2 Antibody Detection

Area of Science:

• Immunology
• Virology
• Biotechnology

Background:

• The COVID-19 pandemic necessitates ongoing monitoring of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody responses due to emerging variants.
• Multiplex immunoassays offer sensitive and specific detection of antibodies, complementing PCR tests.
• Existing serological assays require improvement in accuracy and efficiency for reliable SARS-CoV-2 detection.

Purpose of the Study:

• To develop an advanced peptide-based multiplex serological assay for enhanced SARS-CoV-2 antibody detection.
• To evaluate the performance of novel antigen-fused peptide epitopes (FEPs) derived from SARS-CoV-2 spike and nucleocapsid proteins.
• To assess the potential of FEPs for cost-effective and accurate serological diagnostics.

Main Methods:

• In silico molecular docking simulations were used to validate selected peptide epitopes.
• Three distinct fusion-epitope peptides (FEPs) were synthesized and tested using enzyme-linked immunosorbent assay (ELISA).
• A total of 145 serum samples (110 COVID-19 positive, 35 negative controls) were analyzed.

Main Results:

• The developed FEP antigens demonstrated superior sensitivity, specificity, and accuracy compared to single peptide epitopes or mixtures.
• Data indicate that FEPs significantly enhance the performance of SARS-CoV-2 antibody detection assays.
• The FEP concept proved effective in distinguishing between COVID-19 positive and negative serum samples.

Conclusions:

• The novel peptide-based multiplex assay utilizing FEPs offers a significant improvement in SARS-CoV-2 antibody detection.
• This FEP approach is adaptable for multiplex immunoassays targeting various pathogens beyond SARS-CoV-2.
• The advanced serological assay holds promise for the development of commercial point-of-care diagnostic tests.