Which mechanism explains why antibody affinity for a pathogen increases over time following vaccination, despite the limited diversity initially?

💡 Explanation

Somatic hypermutation introduces point mutations in antibody genes; B cells displaying higher affinity antibodies are preferentially selected for survival and proliferation via affinity maturation. This leads to antibodies with increased binding strength over time, because higher affinity B cells outcompete lower affinity cells, rather than directly mutating or activating complement.

• Following a mRNA vaccine booster, which mechanism explains the enhanced antibody response compared to the primary series, demonstrating long-term immunological memory?
• Which effect occurs when decreased tubular fluid flow disrupts renal electrolyte balance?
• In erythrocytes, what causes hemolytic anemia when a G6PD deficiency exists during a malarial infection treated with primaquine?
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• Which outcome follows restricted alveolar diffusion rates in patients with emphysema?
• What causes the 'fight or flight' response to subside after the perceived threat has passed?