Figure 4.

Villin-CreER^T2 Toxicity Is Mitigated by Delay and Reduced TX Dose

(A) Body weight data from Villin-CreER^T2 mice treated with VEH or TX daily for 5 days, followed by γ-irradiation after a 7-day delay (n = 3–4 mice/group).

(B–J) EdU-stained duodenal tissue sections (B, C, F, and G) at 3DPI (B and C) and 5 DPI (F and G). (D and H) Proliferation, (E and I) regenerating crypts, and (J) villus height were quantified.

(K) Western blot analysis probing for γ-H2AX, CC3, and GAPDH, using duodenal crypt lysates from Villin-CreER^T2 mice 7 days post treatment.

(L and M) γ-H2AX (L) and CC3 (M) band signals were quantified and are displayed as means ± SEM (n = 3 mice/group).

(N–T) qPCR gene amplification of cloxP normalized to Gapdh (N) (n = 6 mice/group). TUNEL staining of duodenum of non-irradiated (O) “delayed” VEH- or TX-treated Villin-CreER^T2 mice, (Q) Villin-CreER^T2 mice administered five daily doses of 50 mg/kg TX and analyzed 1 day later (5 × 50), and (S) Villin-CreER^T2 mice administered a single dose of 100 mg/kg TX and analyzed 1 day later (1 × 100). Organoid-forming efficiency was also determined for (P) delayed, (R) 5 × 50, and (T) 1 × 100 VEH- and TX-treated Villin-CreER^T2 mice (n = 3–9 mice/group with three technical replicates per mouse.

^∗p < 0.05 by Student's t test). Scale bars, 100 μm. See also Figure S4.