A rapid and simple method for measuring thymocyte apoptosis by propidium iodide staining and flow cytometry

Cooperative activity between HER oncogenes and the tumor suppressor IRF-1 results in apoptosis

“…Twenty-®ve per cent of the cells with active HER1 and IRF-1 showed subdiploid DNA (fragmented DNA) (data not shown) (Nicoletti et al, 1991). Cells in which either IRF-1 or HER1 were activated alone did not show DNA fragmentation.…”

“…Annexin V staining was performed according to the manufacturer's instructions (Clontech). DNA degradation was assessed by determination of DNA fragmentation after lysing the cells in a hypotonic bu er (0.1% sodium citrate, 0.1% Triton X-100) containing 50 mg/ ml propidium iodide as described by Nicoletti et al (1991) and analysed by¯ow cytometry using a FACScan analyser with CELLQUEST software (Becton-Dickinson, Heidelberg, Germany). In all cases 10 000 cells were analysed.…”

Role of caspases and possible involvement of retinoblastoma protein during TGFβ-mediated apoptosis of human B lymphocytes

“…Brie¯y, cells (10 6 ) were washed in PBS and resuspended in 1 ml hypotonic uorochrome solution (50 mg ml 71 propidium iodide in 0.1% sodium citrate plus 0.1% Triton X-100) (Sigma, St Louis, MO, USA). Samples were placed at room temperature for 1 h before¯ow-cytometry analysis of PI¯uorescence of individual nuclei using a FACScan¯ow cytometer (BectonDickinson) as described elsewhere (Nicoletti et al, 1991). Debris were excluded from analysis by raising the forward scatter threshold.…”

Caspase-dependent cleavage and inactivation of the Vav1 proto-oncogene product during apoptosis prevents IL-2 transcription

“…Accordingly, caspases are ordered into three groups: group I enzymes (caspase-1, -4 and -5) which are rather promiscuous compared with other caspases, group II enzymes (caspase-2, -3 and -7) and group III enzymes (caspase-6, -8, -9 and -10) (GarciaCalvo et al, 1998). Caspases are synthesized as catalytically inactive proenzymes and their activation results in the proteolytic removal of the prodomain and the formation of an active tetramer, which is composed of two heterodimers formed by a small and a large subunit (NunÄ ez et al, 1998). The apoptotic program is started by so-called initiator caspases such as caspase-8 and caspase-10, which become activated at the death receptors.…”