Figure 7.

The differences in Ca²⁺ influx were eliminated by the application of 10 μm 2-aminoethyldiphenyl borate (2-APB). Kinetics of intracellular [Ca²⁺] (as ratio 340/380) of CD4⁺ T cells stimulated by Chinese hamster ovary (CHO) cells loaded with 2 μg/ml double single-chain fragment variable (dscFv) anti-CD33/anti-CD3 together with 10 μg/ml sc CD80/anti-CD33 or sc CD86/anti-CD33. CD4⁺ T cells were pre-stimulated with anti-CD3/anti-CD28-coated beads for 5 days. After 1000 seconds, cells were treated with thapsigargin (TG) in the absence of extracellular Ca²⁺ to completely deplete Ca²⁺ stores. A Ca²⁺ concentration of 0.25 mm was added to analyse Ca²⁺ entry. Finally, 10 μm 2-APB and 100 μm 2-APB were added. Numbers of analysed cells are given in the bars. (**P < 0·01).