Figure 7: Cell proliferation and apoptosis induction in human PBLs incubated in MMG and in 1 g. (a) T-cell cloning assay performed at the end of 24 h, 48 h, and 72 h of incubation in the two gravity conditions. Data are means ± S.E. from thirteen independent experiments. (b) Apoptotic index at the end of incubation for 24 h and 48 h in MMG and 1 g determined by nuclear chromatin condensation with DAPI staining. (c) Caspase-3 activation at the end of 24 h and 48 h incubation in MMG and 1 g assessed by fluorimetric assay (a.u. arbitrary units). Data in (b) and (c) are means ± S.E. from 3-4 independent experiments ( , t-test).