Redefining long-lived plasma cells by timestamping: isotype- and tissue-specific logic of plasma cell longevity

Abstract

Long-lived plasma cells have traditionally been viewed through the lens of bone marrow-resident IgG-secreting cells that maintain systemic serological memory. However, recent timestamping approaches and isotype-specific analyses have revealed diverse trajectories toward plasma-cell longevity. Plasma-cell longevity is not specified at a single developmental checkpoint, but emerges through a multi-step process involving the timing and site of plasma-cell generation, migratory competence, entry into and adaptation to tissue niches, and progressive maturation. Moreover, emerging studies of non-IgG plasma cells indicate that distinct antibody isotypes use different anatomical and molecular strategies to sustain antibody production. In particular, the recent identification of IgE long-lived plasma cells in secondary lymphoid tissues suggests that the bone marrow is not the only anatomical site capable of supporting durable plasma-cell survival. Together, these findings argue against a single, universal model of plasma-cell longevity and instead support a framework in which antibody persistence is achieved through isotype-specific and tissue-specific logic.