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Poly(ADP-ribose) synthesis: a useful parameter for identifying apoptotic cells.

M Donzelli·C Negri·A Mandarino·L Rossi·E Prosperi·I Frouin·R Bernardi·A Bürkle·A I Scovassi
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Abstract

Cell death by apoptosis was analysed in HeLa cells either treated with the antitumoral drug bleomycin or depleted of growth factors by long-term culture without medium change. The interference of apoptosis with normal cell cycle progression was followed by flow cytometry in cells stained with propidium iodide and with antibody to S-phase-related PCNA protein. Bleomycin-treated cells showed a net accumulation in G2/M phase paralleled by the appearance of material with a subdiploid DNA content. Cells with a subdiploid DNA content were also present in growth factor-depleted cultures and were shown to derive from all the cell cycle phases. To identify apoptotic features in HeLa cell cultures, we applied a recently developed assay based on the simultaneous analysis in the single cell of three parameters, namely chromatin condensation, DNA degradation and poly(ADP-ribose) synthesis. Apoptotic cells were visualized by sequential reactions: Hoechst staining, terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling assay and immunoreaction with anti-poly(ADP-ribose) monoclonal antibody. Positive reactions were obtained for cells at different stages of the apoptotic programme showing condensed nuclei, fragmented chromatin and apoptotic bodies.

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ApoptosisBisbenzimidazoleBleomycinCell CycleChromatinCulture MediaDNA FragmentationFlow CytometryHeLa CellsHumansPoly Adenosine Diphosphate RibosePropidiumJournal ArticleResearch Support, Non-U.S. Gov't

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M Donzelli, C Negri, A Mandarino, L Rossi, E Prosperi, I Frouin, R Bernardi, A Bürkle, A I Scovassi. Poly(ADP-ribose) synthesis: a useful parameter for identifying apoptotic cells.. https://doi.org/10.1023/a%3A1026485622824

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