Profiling of SARS-CoV-2 neutralizing antibody-associated antigenic peptides signature using proteome microarray

Area of Science:

• Immunology
• Virology
• Infectious Diseases

Background:

• The antibody response profile during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibody (NAb) decay remains unclear.
• Understanding antibody dynamics is crucial for managing coronavirus disease 19 (COVID-19) and predicting immunity duration.

Purpose of the Study:

• To investigate the characteristics of the humoral immune response in COVID-19 patients, focusing on antibody profiles associated with NAb decay.
• To identify specific SARS-CoV-2 antigenic epitopes that correlate with the presence and levels of NAbs.

Main Methods:

• Utilized a SARS-CoV-2 proteome microarray containing viral antigenic peptides to analyze immunoglobulin G (IgG) antibody responses in longitudinal plasma samples.
• Employed enzyme-linked immunosorbent assay (ELISA) for independent validation of antibody titers.
• Analyzed samples from distinct cohorts, including those infected with the Omicron BA.1 variant.

Main Results:

• Antibodies targeting the S2 subunit (S-82) and open reading frame protein 10 (ORF10-3) were closely associated with the presence of SARS-CoV-2 NAbs.
• S82-IgG titers were significantly higher in NAb-positive samples compared to NAb-negative samples.
• Higher S82-IgG titers correlated with significantly higher NAb titers in a cohort infected with the Omicron BA.1 variant.

Conclusions:

• The study identifies specific antibody signatures, particularly IgG against the S2 subunit (S-82), associated with SARS-CoV-2 NAb levels.
• These findings provide insights into the decay-associated signatures of SARS-CoV-2 NAbs, aiding in the understanding of immune responses post-infection.
• The identified antibody markers may serve as indicators for NAb persistence and humoral immunity.