Modern Research Techniques of Apoptotic Cell Death (Review)

The review concerns modern research techniques of apoptotic cell death in vitro and in vivo. Apoptosis monitoring has been shown to be based on recording characteristic cell changes: integrity loss and depolarization of plasma membrane, phosphatidylserine and phosphatidylethanolamine exposure on cell membrane surface, activation of caspases, mitochondrial membrane depolarization, DNA fragmentation, the changed level of biochemical markers. The major techniques for in vitro apoptosis studies are light and electron microscopy, flow cytometry, fluorescent microscopy, immunohistochemistry, enzyme immunoassay, Western blot, electrophoresis and TUNEL technique. Currently, noninvasive techniques used to study apoptosis in vivo are of great importance since they are capable of recording the process in tissues, organs and the whole body: positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance tomography (MRT), fluorescent spectroscopy, FLIM/FRET-imaging. Great attention is paid to the search for contrast agents specific to various molecules of an apoptotic cascade. The nature of apoptotic reactions has been demonstrated to serve as a marker of chemotherapeutic efficiency and help choosing chemotherapy. A combination of several techniques to study apoptotic cell death has been found to gain its popularity, e.g. SPECT and optical imaging, PET and optical imaging, PET and MRT. In the long term, by means of these techniques it will be possible both to determine the disease severity and also assess the treatment efficiency.

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