Evaluating IL-21 as a Potential Therapeutic Target in Crohn’s Disease

Figure 2

IL-21R mRNA expression in the colon from a patient with Crohn’s disease. IL-21R mRNA expression was assessed by in situ hybridization using the IL-21Ras (a, b, c, e, f, g) and IL-21Rs (d, h) probes on intestines from patients with CD. Colonic IL-21R mRNA-expressing cells are seen as white and black granules in an isolated lymphoid aggregate in the submucosa (white arrow and black arrow in (a) and (e), resp.). IL-21R mRNA expression is seen in the isolated follicle-associated epithelium of the mucosa (white arrow and black arrow in (b) and (f), resp.) and in isolated lymphoid follicles in the submucosa penetrating into the muscularis externa (white and black arrows in c and g, resp.). No specific reaction was observed with the IL-21Rs probe (d, h). The sections were counterstained with haematoxylin/eosin. M: mucosa; ME: muscularis externa; SM: submucosa. Bars: 200 μm (a, c, d, e, g, h) and 50 μm (b, f).