Following mRNA vaccination, which mechanism explains prolonged antibody production against the target antigen in the absence of continuous antigen exposure?

💡 Explanation

The sustained antibody production after mRNA vaccination results from the differentiation of memory B cells into long-lived plasma cells within bone marrow niches. These plasma cells continuously secrete antibodies, because this is driven by signals within the bone marrow microenvironment, therefore leading to prolonged immunity rather than requiring continuous antigen stimulation, which would necessitate a persistent infection or repeated vaccination.

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