Antibody-mediated feedback modulates interclonal competition in the germinal center

Area of Science:

• Immunology
• Molecular Biology
• Vaccine Development

Background:

• Prior immune responses and their antibodies regulate B cell activation and germinal center (GC) access during recall immunization.
• The influence of antibodies produced during an ongoing immune response on contemporaneous GCs remains less understood.

Purpose of the Study:

• To investigate how antibodies generated during an active immune response affect the dynamics and outcomes of germinal centers.
• To elucidate the role of antibody feedback in regulating B cell competition and epitope specificity within GCs.

Main Methods:

• Development of mouse models for targeted ablation of plasma cells and antibodies from a specific immune response.
• Analysis of B cell competition and affinity maturation in germinal centers under conditions of modulated antibody feedback.

Main Results:

• Antibody-mediated feedback is not essential for B cell affinity maturation.
• Antibody feedback influences competition among B cells with varying epitope specificities.
• Circulating antibodies reduce the abundance of B cell clones recognizing the same epitopes, thereby shaping epitope dominance within GCs.

Conclusions:

• Antibody feedback represents a mechanism by which ongoing antibody responses can direct epitope specificity in germinal centers.
• These findings have potential implications for designing vaccination strategies to target specific epitopes on complex antigens.