IPEC-J2 cells treated with TLR2 ligand showed a protective effect against DON-induced damage. IPEC-J2 cells were stimulated with 10 μg/mL of synthetic TLR2 ligand, PCSK or LTA-BS and then treated with or without DON (2 μg/mL) for 24 or 48 h. A TEER values were examined using epithelial voltohm meter. Data represent mean ± SD of TEER (n = 3). *P < 0.05; **P < 0.01, determined by one-way ANOVA with Tukey’s posttest at each time point. NT denotes no treatment. B Viability of the cells was examined by MTT assay at 48 h after DON treatment (n = 4). *P < 0.05, determined by two-way ANOVA with Bonferroni’s post. C Protein levels of claudin-3 and ZO-1 at 48 h after DON exposure were examined from whole-cell lysates by Western blot assay. β-actin was used as an internal control. D ZO-1 expression was visualized using confocal microscopy after staining with anti-ZO-1 antibody conjugated with Alexa fluor 488-FITC (green) and nuclei (DAPI; blue). The representative figure from four similar results is shown. Scale bar = 50 μm.