In accordance with the histology results, the expression of the typical tight junctions of claudin-2 (Cldn2), zonula occludens1 (ZO-1), and occludin (Ocln) and small intestinal mucus protein mucin 2 (Muc2) at the mRNA levels remained unchanged in the advanced fibrosis group (Figure 6B). The gene discussed is CLDN2; the disease is fibrosis.