Figure 4.

Apoptosis induction in HMT-3522 cells by inhibitory β1-integrin function blocking antibodies. Apoptotic labeling indices calculated for S-1 and T4-2 cultures treated with inhibitory β1-integrin antibodies for 4 d in 3-dimensional cultures: Greater than 70% of S-1 cells were induced to undergo apoptosis within 4 d of incubation with β1-integrin function blocking antibody (S-1 β1) while the level of basal apoptosis was less than 5% in the isotype controls (S-1 IgG). In contrast T4-2 cells similarly treated (T4 β1) were refractory and had an apoptosis rate comparable to basal levels (T4-2 IgG). Results are the mean and SE of 3–6 separate experiments of duplicates.