Fig. 7

Immunohistochemistry analysis of IgA-secreting cells in the intestinal epithelium of intragastrically treated mice. IgA-secreting cells were stained with dark brown. Images of the intestinal epithelium, representative fields of duodenum (a-d), jejunum (e-h) and ileum (i-l) are shown for PBS group (a, e, i), B.s-CotC spores group (b, f, j) and B.s-CotC-CsPmy spore group (c, d, g, h, k, l). m Integrated option density (IOD) of IgA-secreting cells (*P < 0.05). Images in panels a, b, c, e, f, g, i, j and k are taken at a magnification of 100×, those in panels d, h and l) are taken at a magnification of 200×. The arrows indicate the IgA-secreting cells. Scale-bars: a-c, e-g, i-k, 100 μm; d, h, l, 50 μm