Showing papers on "Apoptosis published in 1981"
TL;DR: Murine lymphoid cell lines and rat thymocytes treatedin vitro with glucocorticoid hormones provide a convenient system for studying the nuclear changes in apoptosis, and analogous chromatin condensation, excision and requirements for macromolecular synthesis have been documented.
Abstract: Murine lymphoid cell lines and rat thymocytes treated in vitro with glucocorticoid hormones provide a convenient system for studying the nuclear changes in apoptosis. Morphologically the nucleolus disintegrates and chromatin undergoes an unusual generalized condensation. This is associated with excision of most of the nuclear DNA to short but well-organized chains of nucleosomes, apparently by an endogenous non-lysosomal nuclease. The process is dependent upon macromolecular synthesis and probably is mediated, at least remotely, by the classical steroid-receptor-gene activation pathway. A similar process of chromatin condensation and excision can be produced by the calcium-magnesium ionophore A23187. In other circumstances of 'programmed cell death', analogous chromatin condensation, excision and requirements for macromolecular synthesis have been documented.
179 citations
TL;DR: The dying cells and cell fragments were phagocytosed by epithelial or myoepithelial cells as well as mononuclear phagocytes and undergo lysosomal digestion within the phagosomes, consistent with cell deletion occurring by apoptosis.
Abstract: For the first time the process of epithelial cell deletion was studied within the parenchymal component of the “resting” human breast. The dying cells were initially recognised by specific nuclear changes involving peripheral condensation of the chromatin and nucleolar disintegration. At this stage the cells were retracted from the lumen and had lost desmosomal connections with their neighbours. Within the cytoplasm, there was evidence of ribosomal detachment from the endoplasmic reticulum with the formation of ribosome aggregates. The majority of dying cells were phagocytosed at this stage although a few underwent further morphological changes. These involved blebbing and fragmentation of the nucleus followed by cytoplasmic fragmentation. The dying cells and cell fragments were phagocytosed by epithelial or myoepithelial cells as well as mononuclear phagocytes and undergo lysosomal digestion within the phagosomes. These progressive morphological changes were consistent with cell deletion occurring by apoptosis.
75 citations