Cohort-Specific Serological Recognition of SARS-CoV-2 Variant RBD Antigens.

Area of Science:

• Immunology
• Virology
• Public Health

Background:

• Estimating population cohort responses to novel SARS-CoV-2 variants is crucial for effective control measures.
• Antibody recognition of variant antigens informs vaccine efficacy and public health strategies.

Purpose of the Study:

• To evaluate antibody recognition of SARS-CoV-2 variant antigens by sera from infected and vaccinated individuals.
• To compare antibody responses across different population cohorts against various SARS-CoV-2 variants.

Main Methods:

• Sera from vaccinated donors and four infected patient/donor cohorts were analyzed.
• An anti-SARS-CoV-2 ELISA kit with recombinant antigens from 11 widespread variants, including mutations, was used.
• Antibody binding was compared against wild type (WT) and variant receptor binding domains (RBDs).

Main Results:

• Vaccinated individuals exhibited significantly higher antibody binding (P<0.001) to WT and variant RBDs compared to non-critically ill infected individuals.
• Antibody binding to at least 6 variants, including Variants of Concern (VOCs), was reduced compared to WT in both vaccinated and convalescent non-critically ill groups.
• Sera from critically ill patients were not explicitly compared in this result summary but were included in the study methodology.

Conclusions:

• Understanding cohort-specific antibody titers against WT versus variant RBD antigens is key.
• This knowledge aids in designing variant-specific immunoassays for surveillance.
• It supports the evaluation of the epidemiology of emerging SARS-CoV-2 variants.