Figure 2. The effects of increased intracellular Ca²⁺ on CTL effector functions.

(a,b) Proliferation (CFSE) and expression of CD69 and CD25 on OT-I CD8⁺ T cells after activation with SIINFEKL (N4) peptide, SIIGFEKL (G4) peptide or PBS, in the absence or presence of ionomycin (1 μM, n=3). (c,d) IFN-γ secretion (measured by ELISA) and CD107a expression (measured by flow cytometry) on OT-I CD8⁺ T cells activated with N4 peptide, G4 peptide or PBS, in the absence or presence of ionomycin (1 μM, n=3). (e) N4 peptide, G4 peptide, or PBS loaded target tumour cell killing in the presence of various concentrations of ionomycin (1 μM, n=3). (f) Inhibition of target tumour cell (N4-loaded) killing by aTreg in the absence or presence of ionomycin (1 μM, n=3). (g) TGF- β1 secretion by aTreg with or without ionomycin treatment for 6 h, measured by ELISA of culture supernatants (n=3). Throughout, data are the mean±s.e.m. (b,e) Data were analysed with One-Way ANOVA with a Bonferonni post-test. (c,d,f,g) Data were analysed with Student's t-test.