FIG. 3.

BAT transplant failure is associated with inflammatory changes in adipose tissue. Histological sections of replenished WAT in euglycemic mouse 3 months posttransplant (C) is compared with normal (A) and diabetic (B) controls, and a transplant recipient that reverted to diabetes at 4 months (D). Sections are immunostained for TNF-α (green) and IL-6 (red). All tissues contain some green autofluorsecence, and TNF-α expression is indicated by bright green spots. TNF-α immunofluorescence appears near the right border in the normal section (A), toward the bottom in the transplant (TP) (C), and throughout the section in B and D, colocalizing with IL-6 and appearing yellow-orange. In addition to the presence of larger amounts of inflammatory markers, the failed adipose tissue shows other signs of inflammation, such as enlargement of adipocytes and infiltration of macrophages resulting in thickening of cell membranes. Sections shown are representative of four BAT transplants, two untreated diabetic controls, and two normal animals analyzed. Scale bar, 50 μm. (A high-quality digital representation of this figure is available in the online issue.)