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 A personal apoptosis quality control workstation can provide the individual scientist with the definitive means of identifying the types of cell death that are occurring in particular experimental situations. Biomedical Diagnostics & Research, Inc. will provide free consultation in setting up your workstation.
The types of cell death that can be identified using a microscopy-based workstation include apoptosis, necrosis and cells dying through a mitotic catastrophe [aberrancies in chromosomal condensation and cell cycle progression (aberrant mitoses, mitotic arrest, micronuclei formation)]. Apoptosis is a controlled type of cell death that can be induced by a variety of physiologic and pharmacologic agents. The term "apoptosis" was first coined by John Kerr, an Australian pathologist, after he identified that dying cells in vivo had a common morphologic appearance. The morphologic criteria that he used to describe apoptotic cells included condensation and margination of chromatin, cytoplasmic vacuolization, cellular shrinkage, increase in cellular density, nuclear fragmentation and apoptotic body formation.
 Prolonged cellular stresses, such as oxidative stress and DNA damage, if not defended against, can trigger the apoptotic pathway. Perturbations in signal-transduction pathways, including alterations in intracellular calcium levels, can induce apoptosis as a downstream event. Biochemical markers, such as DNA fragmentation, have been used to identify apoptotic cells. Unfortunately, cells dying by necrosis, a traumatic form of cell death, that is accompanied by cell swelling and lysis, also exhibit DNA fragmentation. In addition, cells with the characteristic morphologic appearance of apoptosis may not show evidence of DNA fragmentation. Cells exhibiting evidence of DNA damage and oxidative stress may, however, recover from those stresses, provided they are equipped with an adequate DNA repair system and an adequate level of stress-response proteins and/or antioxidant defenses.
Treatment of cells with certain pharmacologic agents may not result in either classic apoptosis or classic necrosis. The formation of micronuclei, aberrant mitoses, a mitotic arrest and other cellular perturbations can result in cell death that may be non-apoptotic/non-necrotic in nature. Morphologic criteria using whole-mount preparations that do not require embedment and sectioning procedures, can easily distinguish apoptosis, necrosis, micronuclei formation and a mitotic catastrophe. In addition, a simple quantitation of discrete stages of mitosis in the microscope, can easily reveal a mitotic arrest. The microscope can, therefore, be considered a catch-all for identifying characteristic perturbations that occur in specific experimental situations.
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