Histopathology of small intestinal mucosa cut in transection from an animal in each treatment group (study day 8). The upper panel (row 1) is a low power view (original magnification × 57); the lower panel (row 2) is a high power view (original magnification × 144). Note the diffuse thinning and necrosis of the mucosa with sloughing of intestinal epithelial cells in the control animal (A). There is progressive recovery of the thickness of the mucosa, reduction in inflammatory changes, and improved epithelial architecture with rhG-CSF (B), rhIL-11 (C), and combination therapy with rhG-CSF+IL-11 (D).