The effect of TNF-α neutralizing antibody on the adherent mucus layer and goblet cell mucin in DSS-induced colitis.

<p>Rat colonic tissues sections were stained with Periodic acid Schiff reagent to visualize adherent and goblet cell mucin content. <i>A</i>: DSS treatment alone on day 2 showing mucin filled goblet cells (magenta color) and secreted mucin in the lumen (double head arrow) with a modest inflammatory infiltrate. <i>B</i>: TNF-α neutralizing antibody plus DSS treatment on day 2, showing mucus secretion from crypt goblet cells. <i>C</i>: DSS treatment only rat on day 5 showing disrupted crypts, intense inflammatory cellular infiltrate and intense mucus secretion from crypt goblet cells (single head arrow) with loss of the adherent mucus layer (double head arrow). <i>D</i>: TNF-α neutralizing antibody plus DSS treatment on day 5 showing well organized crypts filled with mucin (single head arrow) and an adherent mucus layer (double head arrow) on the surface epithelium. <i>E</i>: DSS treatment on day 9 showing an ulcerated region with a ruptured mucosa with complete loss of crypts. The residual goblet cells adjacent to the ulcer show remnants of mucin. <i>F</i>: TNF-α neutralizing antibody plus DSS treatment on day 9 demonstrating only to the surface mucosa (double head arrow) and the deep crypts show evidence of mucin in goblet cells beneath the lesions (single head arrow). Scale bar represents 25 µm.