Fig. 1.

Effect of short-term MR1 single treatment on intrahepatic islet survival in vivo. (A) Schematic illustration of the experimental setup. Diabetic C57BL/6 mice were transplanted with BALB/c allogenic islets (700 IEQ) through the cecal vein route. Anti-CD154 mAbs (MR1) were intraperitoneally administered on days −1, 0, 1, 3, 5, and 7 (n = 8). Nontreated mice were used as controls (n = 4). (B) blood glucose level (BGL) was measured with a OneTouch Ultra device from day 0. The blood was obtained from snipped tail. (C) The survival graph was plotted from B. Statistical significance was determined by the Mantel–Cox (log-rank) test. Asterisk (*) indicates statistical significance (P < 0.05). All normoglycemic mice were sacrificed at 257 DPT (1 to 4) or 105 DPT (#5 to 8) for histologic analysis. (D) Immunohistochemical stain of paraffin-embedded islet-transplanted liver and pancreatic tissues. Section slides were triple-stained with anti-CD3 (brown), anti-insulin (red), and anti-FoxP3 (blue) or mono-stained with anti-insulin (red). I to II (105 DPT), III to VI (257 DPT): liver section of islet-transplanted mouse. VII to VIII: liver section of graft-rejected mouse. IX: pancreatic section of islet-transplanted mouse. X: pancreatic section of non-STZ-treated mouse. Original magnification 200, 100, and 50 μm.

DPT: days posttransplantation; mAb: monoclonal antibody; STZ: streptozotocin.