FIGURE 1.

Basal ROS is elevated in intestinal PC. A, Cartoon of colon crypt showing the orientation of the intact crypts that were isolated from mice and imaged by live-cell fluorescent and light microscopy where CD44− differentiated IECs are at the top and CD44+ ISC/PC are at the bottom. B, Images of intact colonic crypts treated with H₂O₂ with or without 5-ASA stained with the ROS detection reagent (green) and DRAQ5 (blue pseudocolor) to stain all nuclei. Some crypts were not stained with the ROS detection reagent or treated with H₂O₂ as controls. C, Percent change in the relative fluorescent intensity of ROS detection reagent staining between H₂O₂ with or without 5-ASA. Crypt images were analyzed in ImageJ, and calculations were performed using peak values in the lower crypt. Average value of 3 independent experiments is shown (*P < 0.05). D, Flow cytometry data showing the number of ROS detection reagent–stained mouse colon IEC. Live, CD45⁻, CD44+ cells were gated on to determine the mean fluorescent intensity of each cell population, as shown in E of ROS detection reagent–stained cells untreated or treated with H₂O₂, with or without 5-ASA.