Kaplan-Meier cumulative survival curves (a) as well as blood glucose concentrations and histology of the pancreata and graft site (b) for diabetic NOD female mice subjected to transplantation of islets from various donor types in the absence or presence of CFA treatment. Treatment groups A–G correspond to those described in Table 1. Blood glucose concentrations were measured at the indicated times after transplantation. The histology of the pancreas and of the islet graft site under the kidney capsule was examined by staining of paraffin-embedded sections with hematoxylin and eosin. Intense lymphocyte invasion of the pancreatic islets is apparent in groups D and E but not in group F. ×400.

Blood glucose concentrations (left panels) and histology of the pancreata (right panels) of diabetic NOD female mice treated with CFA and intrarenal transplantation of islets from β₂M^–/– C57 mice. The kidneys containing the islet grafts were removed at the times after transplantation indicated by the arrows. The animals were killed at various times thereafter, and the pancreata were subjected to histological staining with hematoxylin and eosin. Representative islets are shown. ×400.

Kaplan-Meier cumulative survival of diabetic NOD mice after removal of alginate-encapsulated islets. Treatment groups A–E correspond to those described in Table 2.

Roles of TNF-α and MHC class I peptide complexes in reversal of diabetes in NOD mice. (a) Effect of TNF-α on the survival of spleen cells derived from a control C57 mouse or from untreated or successfully treated NOD female mice. (b) Effect of TNF-α treatment of splenocytes from diabetic NOD mice on the adoptive transfer of disease and the inability of splenocytes from successfully treated NOD mice to transfer disease. Young male NOD mice were irradiated and then injected with diabetic NOD female splenocytes either immediately after their isolation (left panel, dashed lines) or after incubation for 24 hours in the absence (left panel, solid lines) or presence (middle panel) of TNF-α (20 ng/ml); alternatively, four irradiated hosts each received splenocytes from a different NOD donor with long-term normoglycemia restored by CFA and C57 spleen cell injections (right panel). (c) Flow cytometric analysis of the percentages of CD8⁺CD45RB^high, CD8⁺CD62L⁺, and CD8⁺CD95⁺ cells among splenocytes of mice from various treatment groups. Diabetic NOD females were implanted intraperitoneally with alginate-encapsulated C57 islets. They then received no further treatment (group A), a single bilateral injection of CFA only (group B), or CFA treatment plus biweekly intravenous injections of splenocytes from normal C57 mice (group C), β₂M^–/–, TAP1^–/– C57 mice (group D), or MHC class II^–/– C57 mice (group E). Shaded bars represent C57 control mice (group F) or NOD mice that exhibited normoglycemia and disease reversal after removal of alginate-encapsulated islets (groups C and E); open bars represent untreated NOD mice (group A) or NOD mice subjected to treatments that did not result in disease reversal (groups B and D).

Summary of the histological characteristics of the graft site and pancreas of individual NOD hosts subjected to transplantation of islets from various donor types in the absence or presence of CFA treatment. Animals correspond to those listed in Table 1. Open squares, absence of visible islet structures and of lymphocytic accumulation; open squares with center dots, massive lymphocytic accumulation invading or obscuring islet remnants; shaded squares, viable islets without lymphocytes; shaded squares with center dots, viable islet structures with only circumferential lymphocytic accumulation. Examination of serial longitudinal sections of the entire pancreas revealed the presence of approximately 25–35 islets in control BALB/c mice and approximately 12–20 islets in successfully treated NOD mice (group F). Gp, group; Panc, pancreas. P < 0.0001, group F versus all other groups; P < 0.007, group F versus group D (Wilcoxon test).

Effect of CFA treatment, repeated infusions of C57 splenocytes, and daily insulin injections on glycemic control and islet morphology in diabetic NOD recipients. Blood glucose concentration was monitored for up to 40 days in diabetic NOD females that were treated either with daily injections of insulin alone (controls, n = 4) (a) or with a single bilateral injection of CFA, daily insulin injections (until normoglycemia was restored), and biweekly injections of C57 splenocytes (n = 9) (b). Pancreatic histology was examined by hematoxylin and eosin staining either at the time of death (arrows) of control animals (c) or after the 40-day observation period for animals receiving the experimental treatment; of the latter mice, representative islets are shown for one of the four animals that remained hyperglycemic (d) and for one of the three animals in which normoglycemia was restored (e). ×400.

Blood glucose control and pancreatic islet histology in diabetic NOD mice treated with alginate-encapsulated islets, CFA, and splenocytes from various donor types. Diabetic NOD females were treated as described in Table 2, and data from representative animals of groups B through F are shown. Blood glucose concentration was monitored before and after the removal (arrows) of the alginate-encapsulated islets (left panels). The histology of the pancreas was analyzed at the time of killing, indicated by the last blood glucose measurement; sections were stained with hematoxylin and eosin (middle panels) and/or with aldehyde-fuchsin (right panels). Lymphocytic invasion of islets is apparent in the animals of groups B, D, and F, whereas lymphocytic infiltrates surround the islets in the animals of groups C and E. ×400.