Necrosis Versus Apoptosis

From the work of Wyllie and his colleagues it is now recognized that the death of nucleated cells can be classified into at least two distinct types necrosis or accidental death, and apoptosis (programmed cell death Kerr etal., 1972 Wyllie etal., 1980). 

A prominent biochemical feature of apoptosis is inter-nucleosomal cleavage of chromatin in a pattern indicative of endogenous endonuclease activation (Wyllie, 1981). This creates low molecular-sized fragments of chromatin which are integers of the 180 base pairs of DNA associated with a nucleosome. When DNA extracted from apoptotic cells is subjected to agarose gel elec- 

Flgure 12.1 Electron micrograph of an apoptotic human neutrophil showing the characteristic chromatin aggregation, prominent nucleolus and dilated cytoplasmic vacuoles. Note that the cell membrane is intact and the granule structure appears normal. (EM taken by Jan Henson), (x 11 000). 

It is now recognized that the process of apoptosis can be influenced by external mediators which are to some extent cell lineage restricted, but can also be modulated by internal genetic influences. However, the biochemical processes integrating the external influences, the genetic influences and how they relate to the nuclease responsible for chromatin cleavage and the cell surface changes 

The speed with which monocyte-derived macrophages recognize, ingest and destroy apoptotic neutrophils in vitro is quite remarkable. Individual macrophages can ingest several neutrophils (see Fig. 12.3), and once 

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Lizard, G., Monier, S., Cordelet, C., Gesquiere, L., Deckert, V., Gueldry, S., Lagrost, L., and Gambert, P., 1999, Characterization and comparison of the mode ofceU death, apoptosis versus necrosis, induced by 7beta-hydroxycholesterol and 7-ketocholesterol in the cells of the vascular wall, Arten oicZer. Thromb. Vase. Biol. 19 1190-1200. 

The identity of factors released from damaged neurons to signal microglial cell activation may depend upon which type of neural cell is damaged, neuron versus glial, and on the the toxin or stimulus, glutamate versus /1-amyloid versus a-synuclein, and the nature of cellular death, apoptosis versus necrosis. Similarly, the molecular mechanisms and internal and external factors that modulate the dynamic aspects of acute and chronic inflammation in cell injury mediated by glutamate remain unclear. It also remains unclear to what extent inflammation is beneficial... 

Y. Luo, D. Kessel (1997). Initiation of apoptosis versus necrosis by photodynamic therapy with chloroaluminum phthalocyanine. Photochem. PhotobioL, 66, 479 83. 

The PDT mechanism of cell death is also still discussed among PDT specialists direct tumoral effect, vascular effect, apoptosis versus necrosis and so on. Such discussions also impair PDT credibility and prevent focus on the main PDT advantages and its efficacy. 

F. 5 Mitochondria as focal points in drug-induced liver injury, (a) Thcau are two levels of mitochondrial participation in DILI (1) final common pathway of cell death in liver - bax, bak, bim, tbid versus bcl-xl, mcl-1, bcl2 regulating mitochondrial outer membrane permeabilization and apoptosis (possibly also MPT and necrosis) which responds in external signals (e.g., TNF or FasL)... 

EFFECTS OF ATMOSPHERIC-PRESSURE AIR PLASMA ON BACTERIA AND CELLS DIRECT VERSUS INDIRECT TREATMENT, SURFACE VERSUS IN-DEPTH TREATMENT, AND APOPTOSIS VERSUS NECROSIS... 

Apoptosis Versus Necrosis in Piasma Treatment of Cells Sublethal Plasma Treatment Effects... 

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