Figure 2: Detection of radiation-induced apoptotic epithelial cells in the small intestine, as determined by TUNEL staining. Mice received intraluminal infusion of AxCA-Bcl-XL (A), AxCA-lacZ (B) or PBS (C) with Pronase MS® treatment. Twenty four hours later, mice underwent 15-Gy whole body irradiation and samples were obtained at 6 hours after irradiation. (A-C) TUNEL staining. Original magnification ×400. (D) Number of TUNEL staining-positive apoptotic epithelial cells among 50 crypts. *p< 0.01 versus the other two groups; n=5-6 in each group.