HPS4-YC downregulated tight junction protein levels in the lungs of piglets. A Immunofluorescence staining of ZO-1 and occludin in the lungs. Blue, the nucleus. Red, ZO-1 or occludin. Scale bar, 50 μm. B Protein levels of ZO-1 and occludin in the lungs were analyzed by Western blot. HPS4-YC decreased the expression of ZO-1 and occludin. C mRNA levels of ZO-1 and occludin in the lungs were analyzed with qRT-PCR. The results were in accordance with cell experiments. Data are shown as the mean ± SD of three independent experiments. Significant differences were determined using the Student t test. *, P < 0.05; **, P < 0.01.