mRNA vaccination compared to infection elicits an IgG-predominant response with greater SARS-CoV-2 specificity and...

Area of Science:

• Immunology
• Virology
• Vaccinology

Background:

• The COVID-19 pandemic spurred development of mRNA vaccines, such as BNT162b2, utilizing lipid nanoparticles for antigen delivery.
• Understanding differences in antibody responses between vaccination and natural SARS-CoV-2 infection is crucial for public health strategies.

Approach:

• Comparative analysis of antibody magnitude and breadth against SARS-CoV-2, its variants, and endemic coronaviruses.
• Study included individuals vaccinated with BNT162b2 and patients with confirmed SARS-CoV-2 infection.

Key Points:

• Vaccination elicits a dominant IgG response, comparable in magnitude to severe COVID-19 cases, unlike infection which shows a mix of IgG, IgM, and IgA.
• Antibody response breadth is reduced against endemic coronaviruses following vaccination compared to infection.
• SARS-CoV-2 variants (B.1.1.7, P.1, B.1.351) demonstrate a consistent hierarchy of decreased antibody recognition in both vaccinees and infected individuals.

Conclusions:

• mRNA vaccination induces a distinct antibody profile compared to natural SARS-CoV-2 infection, characterized by IgG dominance and narrower cross-reactivity.
• The findings highlight the specific immune response elicited by mRNA vaccines and inform ongoing vaccine development and variant surveillance efforts.