Figure 2.

Bystander effect induced in human colon adenocarcinoma LS174T cells when co-cultured with ¹²⁵IUdR-labeled human lymphocytes. The ratio 1:0 represents the control. The total number of cells in each well is kept constant (8 × 10⁵) by the addition of dead spacer cells (except at 1:1, 1:2.5, and 1:5 where no spacer cells were used). Co-cultures at each ratio were done in triplicate and error bars indicate ± SD of the mean (n = 3). *Indicates when p values are < 0.005 by paired Student's t-test.