Major phenotypes of LYVE-1-Cre/iDTR mice after DT administration. Comparisons between control and LCiDT for major findings at 24 hours after DT administration. Each group, n = 4 to 5. *P < .05. (A) Gross images of the abdominal contents. The arrow indicates a hemorrhagic and swollen duodenum, and the arrowhead indicates a hyperemic and enlarged Peyer patch. (B-C) Duodenums and Peyer patches in jejunums stained with hematoxylin and eosin. Scale bars, 200 μm. (D) Quantification of sizes of Peyer patch. (E) LYVE-1+ lymphatic vessels and CD31+ blood vessels in jejunums. Indicated areas (square with white dotted line) are magnified in the right panels. The arrows indicate mucosal lymphatic vessels, and the arrowheads indicate lacteal lymphatic vessels. Scale bars, 100 μm. (F) Quantification of LYVE-1+ area in the jejunum. (G) Images showing abundant distribution of LPS derived from E coli at the base of the villi (arrowheads) and within LYVE-1+ mucosal lymphatic vessels (arrow) of the LCiDT mice at 24 hours after DT administration, whereas LPS is rarely detected in the control mice. 4,6 Diamidino-2-phenylindole (DAPI) staining for nuclei. Scale bars, 50 µm. (H) Serum endotoxin levels. (I) Blood profiles of hemoglobin, hematocrit, neutrophils, lymphocytes, and platelets. NS, not statistically significant.