MSX-122 attenuates colonic damage in mice with experimental colitis.

<p>(A) Colonic sections were stained with H&E. (B) Histological scores were determined by a blinded examination of the sections. n = 16 per group. *, p<0.05 between DSS and DSS + MSX-122 treated mice. (C) MPO activity was measured in the colons of control, DSS-, and DSS/MSX-122-treated mice. MPO activity was expressed as unit of MPO per mg colonic lysate. n = 12. *, p<0.05. (D) The presence of CD4⁺ lymphocytes was detemined by immunohistochemically using anti-CD4 antibodies. CD4⁺ lymphocytes are depicted in the brown color and nuclei were counter-stained in the blue color. Quantification of CD4⁺ lymphocyte per high powered field is shown. n = 4–5. *, p<0.01. (E) Representatives of immnohistological staining of CXCR4-positive cells are shown. CXCR4 protein is depicted by the brown color, whereas nuclei were counter-stained in blue. 1, control; 2, 7 days DSS; 3, 7 days DSS + 3 days or recovery; 4, 7 days DSS/MSX-122; and 5, 7 days DSS/MSX-122 + 3 days MSX-122. (F) Quantitative analysis of CXCR4-positive immune cells in the colon is shown. *, p<0.01. MSX-122 blocks migration of CXCR4 positive cells. (G) Expression of cytokine mRNAs was determined by qRT-PCR. Expression levels of cytokines were normalized to 18S. n = 8. *, p<0.05. (H) MSX-122 attenuates TNF-α secretion induced by invasive <i>E.coli</i>. J774A.1 macrophages in triplicates were infected with overnight cultures of commensal <i>E.coli</i> EFC-1, CD-isolated <i>E.coli</i> LF82 or 13I at MOI 10∶1 for 3 h. Following 3 h infection, macrophage culture was washed and incubated for additional 21 h in a growth medium containing antibiotics and MSX-122. The amounts of TNF-α in the supernatant were quantified by ELISA. Representative data from three independent experiments, each performed in triplicate, are shown. *, p<0.05.