Apoptotic effect of mAbs on NHL cell lines. (A) Induction of apoptosis was evaluated by flow cytometry determination of haploid DNA on the cell line panel with and without a second antibody for cross-linking, followed by staining with propidium iodide. Error bars represent SD. (B) Apoptosis was quantified in Daudi using annexin V/7-AAD staining. Percentage of apoptotic cells refers to the annexin V-positive, 7-AAD-negative cells; percentage of dead cells refers to the annexin V-positive, 7-AAD-positive population. Cells were 97% viable prior to treatment. (C) Changes in mitochondrial membrane potential were measured by flow cytometry using the JC-1 reagent following antibody incubation in the presence or absence of second antibody. GAM indicates F(ab′)2 goat anti-mouse IgG, Fcγ specific; GAH, F(ab′)2 goat anti-human IgG, Fcγ-specific antibody.
