Antibody affinity maturation in selectively bred high and low-affinity mice.

Area of Science:

• Immunology
• Genetics

Background:

• Antibody affinity maturation is crucial for effective adaptive immunity.
• Genetic selection of mice has generated lines with distinct antibody production characteristics.

Purpose of the Study:

• To investigate the antibody production and affinity maturation in selectively bred mouse lines.
• To elucidate the cellular mechanisms underlying impaired antibody affinity maturation in specific mouse lines.

Main Methods:

• Determining serum antibody affinity in high-affinity, low-affinity, and low-nonmaturing (N/M) mouse lines.
• Administering T-dependent (human serum albumin, dinitrophenylated bovine gamma-globulin) and T-independent (dinitrophenylated Ficoll) antigens in saline and adjuvant.
• Assessing the effects of carrier priming and cyclophosphamide treatment on antibody affinity.

Main Results:

• Low-N/M mice exhibited impaired affinity maturation to T-dependent antigens, unlike high and low-affinity lines.
• Low-N/M mice showed normal antibody affinity maturation to T-independent antigens.
• Carrier priming led to greater suppression of antibody affinity in low-N/M mice, while cyclophosphamide increased affinity in these mice.

Conclusions:

• The failure of antibody affinity maturation in low-N/M mice is likely due to elevated suppressor T cell activity.
• These selectively bred mouse lines serve as a valuable model for studying the cellular basis of antibody affinity maturation control.