Rat tissues processed with immunohistochemistry to highlight the expression of Tlr2.

<p>Panel a: spleen section used as positive control (original magnification, 40×); panel b: colon section containing an MDF (arrow) surrounded by normal mucosa; Tlr2 was weakly expressed by epithelial cells facing the gut lumen in both normal mucosa and MDF (original magnification 10×); panel c: the same MDF of panel c, shown at higher magnification (40×); panel d: colon section with normal mucosa and gut associated lymphatic tissue (GALT, indicated by an arrow) (original magnification 10×): panel e: the same GALT of panel d, shown at higher magnification (40×).</p

Representative examples of histological sections of rat colon processed with FISH (Cy3-conjugated EUB338 probe).

<p>Panel a: normal proximal colon showing a direct contact between bacteria (bright yellow signal) and the intestinal epithelium (E) (original magnification 4×). Panel b: bacteria inside a crypt in the proximal colon (original magnification 100×). Panel c: normal distal colon showing bacteria (bright yellow signal) separated from the epithelium (E) by a layer of mucous (M) (original magnification 40×). Panel d: section of a colonic tumor (T) and its adjacent normal mucosa (E) stained with DAPI (original magnification 4×); the boxed region is shown enlarged in panel e. Panel e: presence of bacteria (arrow) at the interface between tumor (T) and normal mucosa (E) (original magnification 40×). Panel f: section of an unopened colon containing an MDF (boxed) stained with DAPI (original magnification 4×); the boxed region is shown enlarged in panel g. Panel g: no bacteria are present in the MDF (original magnification 40×). Panel h: section of an unopened colon containing a tumor (T) stained with DAPI (original magnification 4×); the boxed region is shown enlarged in panel i. Panel i: no bacteria are present in the tumor (original magnification 40×).</p

Genes associated to the Tlr pathway: list of the statistically significant up and down-regulated genes in the MDF.

a<p>Genes for which the comparison between the ΔCt of the MDF with that of the corresponding normal mucosa was statistically significant (p<0.05, using t-test for paired samples).</p>b<p>For each gene, fold change between MDF and normal mucosa was calculated with the 2^−ΔΔCT method <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0029918#pone.0029918-Schmittgen1" target="_blank">[26]</a>; values are means±SE (n: 7 MDF analysed).</p