Epithelial barrier functions is impaired in GF mice.

<p>(A) Real-time quantitative RT-PCR analysis of mRNA expression of <i>Cldn7, Ocln, Tjp1, Ctnnb1, Cdh1</i> in colonic ECs in SPF (n = 4) or GF (n = 4) mice. Values were normalized to that of <i>Gapdh</i>. Data are representative of two independent experiments and show mean values ± S.D. of 4 samples performed in duplicate. *P<0.05. (B) Mouse colonic tissue was stained with anti-occludin antibody. Sections were analyzed using a confocal microscope. Bars, 50 µm. Data are representative of two independent experiments. (C) SPF (n = 8) or GF (n = 8) mice were administered 4% DSS by drinking water for 3 days. Survival rates of the indicated mice are shown. Body weight changes relative to the value prior to colitis induction are shown. Data are mean ± S.E.M of 8 mice at each time point. SPF, specific pathogen free; GF, germ free.