Fig. 3.

Measurement of the cytotoxic activity of PBMC against TF-overexpressing and control HT29 cells. pEGFP-TF transfected and un-transfected HT29 cells (5×10⁴ per well) were labelled with 5 μM SNARF-1 in culture medium (200 μl final volume). Ten random views within each well were recorded using a fluorescence microscope. The cells were then challenged separately with five preparations of isolated PBMC at a ratio of 10:1 (PBMC: HT29). After 4 h incubation at 37°C, ten random sectors were analysed as before. Analysis was carried out using the Image Pro plus program and the data were calculated as the percentage reduction in cell number after incubation with PBMC against the initial number of viable HT29 cells. The data represent the mean of duplicates±standard deviation