Secretional Blockade by VSL#3 Figure 8. Intestinal segment specific effects of VSL#3 on experimental inflammation correlate with IP-10 expression in IEC. IL-102/2 mice were fed VSL#3 (1,36109 cfu/mouse/day) (n = 14) or placebo (n = 12) analogous to wt mice (n = 9) for 21 weeks. Mice were sacrificed at 24 weeks of age and histopathological scoring was performed by blindly assessing the inflammation between 0 (not inflamed) and 12 (highly inflamed). Figure A and B show the median histopathologic score of the cecum and colon of IL-102/2 mice in the study. (C) Cecal and colonic IEC were isolated together and proteins (50 mg) as well as mRNA of all mice in a group were analyzed for IP-10 expression by Western blot or RT-PCR (D) Immunohistochemical staining of IP-10 in cecal tissue sections was performed. The upper row shows representative pictures (three mice per group were analysed) of stained tissue sections (IP-10 (green), DAPI (blue)) and the lower row shows representative false colour confocal images of the stained tissue sections ((IP-10) green, DAPI (red)). Arrows indicate regions that show elevated IP-10 expression. doi:10.1371/journal.pone.0004365.g008 probiotic treatment between the two intestinal compartments might be due to the lower inflammatory grade in the cecum compared to the colon in IL-102/2 mice or due to differences in the bacterial colonisation. The discrepancy to previously published studies, showing anti-inflammatory effects of VSL#3 in the cecum and colon [15], may presumably be due to differences in the composition of the intestinal microbiota of the IL-102/2 mice in different animal facilities or the time point of intervention. 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