Following SARS-CoV-2 mRNA vaccination, which mechanism explains why memory B cells produce antibodies with increased binding strength to viral antigens upon subsequent exposure?

💡 Explanation

Affinity maturation increases antibody binding strength because somatic hypermutation followed by selection for high-affinity B cells occurs in germinal centers. Therefore, memory B cells generated post-vaccination exhibit improved antigen binding, rather than reduced mutation or altered class switching.

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