Apoptotic Bodies: Formation Mechanisms, Source-Dependent Heterogeneity, and Therapeutic Potential

Apoptotic bodies (ApoBDs) are membrane-bound vesicular structures generated during the late stages of programmed cell death. They were traditionally regarded as inert cellular debris that is removed by phagocytes, but increasing evidence suggests that ApoBDs are not simply passive byproducts of apoptosis. Instead, they can participate in intercellular communication and contribute to the maintenance of tissue homeostasis. Their formation involves coordinated cytoskeletal remodeling, membrane blebbing, and vesicle fragmentation, which together package diverse nuclear and cytoplasmic components into membrane-enclosed structures. Recent studies further indicate that the composition and biological effects of ApoBDs are closely related to their cellular origin. ApoBDs derived from stem cells, immune cells, and tumor cells may carry different cargos and exhibit distinct functional tendencies, leading to different effects on recipient cells in different biological contexts. These source-related differences not only reflect the heterogeneity of ApoBDs, but also distinguish them from other extracellular vesicle subtypes. In this review, we summarize recent progress in the mechanisms of apoptotic body formation and discuss how cellular origin influences their cargo composition, recognition, uptake, and downstream biological effects. We also discuss their potential relevance in tissue repair, immune regulation, disease intervention, and biomarker-related applications, while highlighting current limitations in this field, including methodological inconsistency, insufficient standardization, and the challenges that still restrict their further translational application.