Cell death in the development of the human retina: phagocytosis of pyknotic and apoptotic bodies by retinal cells.

Apoptosis is a natural form of cell death and has features in common with aspects of cell deletion observed in the course of human retinal development. In this report, we describe the occurrence of apoptotic cells in various layers of the developing retina. Pyknotic residues were observed within phagosomes of neighbouring retinal cells. Our observations imply that most of the debris resulting from cell death is taken up by adjacent tissue cells rather than by mononuclear phagocyte series cells (macrophages) during early stages of human retinal development.