Figure 4.

CD86 costimulation increases net Ca²⁺ entry in effector T cells. (a–d) Kinetics of intracellular [Ca²⁺] (as ratio 340/380) of parental Jurkat T cells, E6-1 Jurkat T cells, naïve, unstimulated primary CD4⁺ T cells or effector T cells. Effector T cells were prestimulated for 4 days with phytohaemagglutinin and interleukin-2. Cells were stimulated by Chinese hamster ovary (CHO) cells loaded with 2 μg/ml of dscFv anti-CD33/anti-CD3 alone or together with 10 μg/ml of sc CD80/anti-CD33 or sc CD86/anti-CD33. (e–h) CD28 and a cytotoxic T-lymphocyte antigen 4 (CTLA-4) staining of the corresponding cell type are shown. Scale bars represent 5 μm (**P < 0·01).