Memory B-Cell Development After Asymptomatic or Mild Symptomatic SARS-CoV-2 Infection.

Area of Science:

• Immunology
• Virology
• Infectious Diseases

Background:

• The immunological consequences of asymptomatic SARS-CoV-2 infection, particularly memory B cell development, remain incompletely understood.
• Understanding the adaptive immune response to SARS-CoV-2 is crucial for vaccine development and public health strategies.

Purpose of the Study:

• To compare antibody titers and memory B cell responses in asymptomatic versus symptomatic SARS-CoV-2 infected individuals.
• To investigate the correlation between antibody levels and memory B cell frequency following SARS-CoV-2 infection.

Main Methods:

• SARS-CoV-2 PCR-positive Marine recruits were categorized as asymptomatic or symptomatic.
• Spike-specific antibody titers (IgG, IgA) and pseudovirus neutralizing antibody titers were measured.
• Memory B cell frequencies were assessed and correlated with antibody responses.

Main Results:

• Asymptomatic participants showed similar spike IgG, spike IgA, and pseudovirus neutralization titers compared to symptomatic participants.
• A significant positive correlation was observed between pseudovirus neutralization titers, spike IgG titers, and memory B cell frequency.
• These findings suggest robust humoral and cellular immune memory formation regardless of symptom status.

Conclusions:

• Asymptomatic SARS-CoV-2 infection elicits comparable antibody and memory B cell responses to mild symptomatic infection in young adults.
• The development of immunological memory following SARS-CoV-2 infection is not solely dependent on the presence of symptoms.
• These results have implications for understanding long-term immunity and vaccine efficacy in diverse infection scenarios.