Resident phagocytes promote non–cell-autonomous fragmentation of apoptotic cells

Abstract

Phagocytosis of apoptotic cells maintains tissue homeostasis and regulates inflammation. A proposed facilitator of apoptotic cell clearance is the fragmentation of these cells into apoptotic bodies (ApoBDs) through cell-autonomous processes involving caspases and cytoskeletal rearrangement. Although this fragmentation process is considered a hallmark of apoptosis, its progression in tissue environments remains underexplored. Here, we examine the in vivo apoptotic dynamics of mouse thymocytes and pluripotent cells from zebrafish embryos. We show that the in vivo biogenesis of ApoBDs is independent of known cell-intrinsic regulators. Instead, fragmentation depends on actin-rich protrusions fro..