Bone-marrow mesenchymal stem cells reduce rat intestinal ischemia-reperfusion injury, ZO-1 downregulation and tight junction disruption via a TNF-α-regulated mechanism

Figure 6 Bone-marrow mesenchymal stem cells and tumor necrosis factor-α blockade attenuate zona occludens 1 downregulation after intestinal ischemia/reperfusion injury. The mucosal tissue sections after ischemia/reperfusion (I/R) injury were immunohistochemically labeled for zona occludens 1 (ZO-1) (brown) and counterstained with hematoxylin (blue). A: Sham group; B and C: In the normal saline + I/R injury group, decreased ZO-1 staining (arrows) was observed in the epithelial cells 2 h (B) and 6 h (C) after I/R; D-F: ZO-1 was not obviously affected in the bone-marrow mesenchymal stem cells + I/R injury group (D), anti-tumor necrosis factor (TNF)-α + I/R injury group (E), or anti-TNF-α R1 antibody + I/R injury group (F) at 6 h; original magnification, × 400.