title: DNA fragmentation and morphological changes in apoptotic human lymphocytes.
abstract: Cell suspensions enriched in cells at various stages of apoptosis were obtained by separation of irradiated human peripheral blood lymphocytes on density gradients at different post-irradiation times. The state of DNA fragmentation in the cells was determined by comet assay and pulsed field gel electrophoresis. The morphologically distinguishable features of apoptosis such as chromatin condensation and cell shrinkage correlated with discrete stages of DNA fragmentation. It was found that >/=50 kbp fragmentation of DNA occurs already in cells of normal density whereas the subsequent DNA fragmentation onto fragments <50 kbp occurs in parallel with cell shrinkage and simultaneous increase in cell density. The observed stages of DNA fragmentation seem to be separated in time that could allow in case of abortive apoptosis formation of chromosomal aberrations.
authors.affiliation: Department of Genetic and Cellular Toxicology, Stockholm University, Sweden. stefan.czene@genetics.su.se
authors.forename: Stefan
authors.initials: S
authors.lastname: Czene
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Testa
authors.forename: Jonas
authors.initials: J
authors.lastname: Nygren
authors.forename: Igor
authors.initials: I
authors.lastname: Belyaev
authors.forename: Mats
authors.initials: M
authors.lastname: Harms-Ringdahl
mesh_terms: D017209:Apoptosis; D002478:Cells, Cultured; D020552:Comet Assay; D004247:DNA / Q000378:metabolism; D053938:DNA Fragmentation; D004587:Electrophoresis, Agar Gel; D006801:Humans; D008214:Lymphocytes / Q000166:cytology / Q000378:metabolism*; D008856:Microscopy, Fluorescence
chemical_list: D004247:DNA