Figure 2. Example of heterogeneous calcium patterns of individual responding cells activated on material surfaces functionalised with anti-CD3_(Fab) + anti-CD28.

(a) Three examples are shown here, with individual fluorescence channels highlighting the simultaneous increase and decrease in F_Em:525 nm (green) and F_Em:660 nm (red), respectively. (b) Wavelet transformations were applied to individual calcium graphs to quantify threshold crossings