Effects of dexamethasone and rituximab on apoptosis.
Dexamethasone- and rituximab-induced apoptosis. (A) Annexin V/propidium iodide staining in Tab cells. Rituximab- and dexamethasone-induced apoptosis of Tab cells as demonstrated by FITC–annexin-V/propidium iodide staining. The AV−/PI− population is shown in the R1 region of the left lower quadrant and represents healthy live cells. The percentages of cells in R1 among the 4 treatment groups are as follows: control, 85% (Ai); rituximab alone, 58% (Aii); dexamethasone alone, 52% (Aiii); and rituximab and dexamethasone, 16% (Aiv). This is a representative Figure of 3 experiments. (B) DNA fragmentation in Tab cells. DNA fragmentation, as a measure of late apoptosis, is induced by the combination of rituximab and dexamethasone. Treatment with both agents simultaneously results in supra-additive sub-G1 DNA content in 3 B-NHL lymphoma cell lines. This shows sub-G1DNA content as a percentage of total DNA in Tab cells treated for 48 hours as follows: control, 5.2% (Bi); 5 μg/mL rituximab, 15.7% (Bii); 10 μM dexamethasone, 22.4% (Biii); and 5 μg/mL rituximab and 10 μM dexamethasone combined, 55.3% (Biv). This is representative of 3 experiments.
