Stable T_reg–T_eff cell interaction with or without CD11c⁺ DCs. (A and B) Alexa Fluor 647–labeled anti-CD11c antibodies or isotype controls were injected into ACE to visualize DCs at the site of T_reg–T_eff cell interaction in islet grafts. (C) The total count for each type of the interactions was calculated from the images in this experiment (mean ± SEM). (D) The interaction times of the different subsets in time-lapse recordings. (E) The relative interaction time is calculated by dividing absolute interaction time with total imaging session length. The data were pooled from 6 videos from three experiments with 5 mice. *, P < 0.05; ***, P < 0.001. Bar, 100 µm.