Morphological and Biochemical Aspects of Apoptosis, Oncosis and Necrosis

Abstract

Recent investigations have demonstrated the need for a precise differentiation of various forms of cell death such as apoptosis, oncosis, necrosis and programmed cell death. Apoptosis is marked by cellular shrinking, condensation and margination of the chromatin and ruffling of the plasma membrane with eventually breaking up of the cell in apoptotic bodies. Cell death marked by cellular swelling should be called oncosis, whereas the term necrosis refers to the morphological alterations appearing after cell death. Apoptosis and oncosis are therefore pre-mortal processes, while necrosis is a post-mortal condition. The term programmed cell death refers to the 'fixed' pathway followed by dying cells, whether or not with the characteristic morphology of apoptosis. Three mechanisms are actually known to be involved in the apoptotic process: a receptor-ligand mediated mechanism, a mitochondrial pathway and a mechanism in which the endoplasmic reticulum plays a central role. All three mechanisms activate caspases which are responsible for the characteristic morphological changes observed during apoptosis. A review of the different methods used for detecting apoptotic cells demonstrates that most of these techniques are not entirely specific.

Induction of interferon‐α production in plasmacytoid dendritic cells by immune complexes containing nucleic acid released by necrotic or late apoptotic cells and lupus IgG

“…delayed release may be due to the retained cell membrane integrity in early apoptotic cells, which is eventually lost during the later stages of apoptosis (49). In contrast to necrosis, many studies show that apoptosis is a "silent" process with regard to inflammation.…”

Fluopsin C induces oncosis of human breast adenocarcinoma cells

“…Fluopsin C induced ATP depletion, ROS generation and Δψ m collapse Several studies have suggested that ROS and cellular ATP play a pivotal role in determining whether cell death is apoptotic or oncotic [2,23,24] . Figure 8A shows that the cellular ATP content of MCF-7 cells in the presence and absence of fluopsin C was significantly decreased.…”

“…Apoptosis and oncosis, two major forms of cell death, have distinct morphological and biochemical features [1,2] . Apoptosis is considered to be the major form of cell death in various physiological events.…”

“…Recently, there has been increasing interest in the mechanistic relationship between cell death via apoptosis and oncosis [2,9] . Emerging evidence has suggested a complex interplay between these two cellular processes, which seem to have some common regulatory mechanisms.…”

Morphological changes in disc herniation in the lower cervical spine: an ultrastructural study

“…At least 27 cells were examined in each sample of the oAF, 23 in the iAF and a minimum of 13 cells in the NP. (a) Necrotic cells were identified when there was loss of integrity of the cell membrane and sometimes the nuclear membrane, together with swelling and vacuolisation of cell organelles and/or loss of organelle membranes [17,18]. (b) Apoptotic cells were identified by shrinking of the cell and blebbing of the cell membrane.…”