Fig 1.

S. Typhimurium ΔaroA infection results in increased mucin secretion in WT mice. (a) Representative PAS/alcian blue staining of Carnoy's solution-fixed cecal tissues at day 0 (uninfected), 3 dpi, and 7 dpi. Original magnification, ×100; bar, 100 μm. (b) Representative Muc2 immunostaining in the cecum using an anti-Muc2 antibody (green) and a DAPI counterstain (for cellular DNA) (blue) at day 0 (uninfected), 3 dpi, and 7 dpi. Original magnification, ×200; bars, 50 μm. (c) S. Typhimurium infection induced significantly higher levels of transcription of the mucin gene Muc2 in the cecal tissues of WT mice than in uninfected samples. Error bars represent SEM from three independent experiments (9 mice per group). Asterisks indicate significant differences (*, P < 0.05) by the Mann-Whitney test.