Fig. 6

Effect of CARDS toxin on inflammatory cell infiltration and mucus secretion in mouse lungs. Following intranasal instillation of CARDS toxin (50 μg/0.5 mL) or equivalent PBS, the mouse lung tissues were harvested for heamatoxylin and eosin (H&E) staining and Periodic acid-Schiff (PAS) staining on the 7th day. Ten bronchial tubes with an inner diameter of 150–200 μm were randomly selected from each section under a light microscope. H&E average score and the percentage of PAS-positive (PAS⁺) epithelial cells in the total number of epithelial cells were analyzed by a pathologist in a blinded fashion. N = 5/group. ^*p < 0.05, ^***p < 0.001. a H&E staining in PBS controls; b H&E staining in CARDS toxin groups; c H&E staining in TNF-α^-/- mice stimulated with CARDS toxin; d PAS staining in PBS controls; e PAS staining in CARDS toxin groups; f PAS staining in TNF-α-/- mice stimulated with CARDS toxin