The Immune Response to SARS-CoV-2 Vaccination: Insights Learned From Adult Patients With Common Variable Immune...

Area of Science:

• Immunology
• Vaccinology
• Infectious Diseases

Background:

• Common Variable Immunodeficiency (CVID) patients exhibit heightened susceptibility to infections.
• Understanding immune responses to novel antigens like SARS-CoV-2 is crucial for CVID patient management.
• Previous studies highlight B and T cell roles in immune responses to infections and vaccinations.

Purpose of the Study:

• To analyze the defective immune response mechanisms in CVID patients following SARS-CoV-2 vaccination.
• To compare immune responses to SARS-CoV-2 in infected versus vaccinated CVID individuals.
• To identify optimal immunization strategies for CVID patients.

Main Methods:

• Analysis of B cell populations (classical memory B cells and atypical memory B cells) and T cell responses post-vaccination in CVID patients.
• Comparison of immune profiles between vaccinated, infected, and convalescent CVID patients.
• Assessment of anti-Spike IgG antibody levels and binding capacity.

Main Results:

• Two-dose mRNA vaccination in CVID patients induced atypical memory B cells (ATM) with limited Spike protein binding, not classical memory B cells (MBCs).
• Variable frequencies of Spike-specific T cell responses were observed in CVID patients post-vaccination.
• Subsequent immunization after SARS-CoV-2 infection enhanced immune responses, generating classical MBCs and antibodies in a significant percentage of patients.

Conclusions:

• Standard SARS-CoV-2 mRNA vaccination in CVID patients yields suboptimal classical memory B cell responses.
• Immunization following SARS-CoV-2 infection appears more effective in generating robust humoral and cellular immunity.
• Developing new preventive strategies, potentially including monoclonal antibodies, is necessary for CVID patients, especially those reinfected.