Histology of a representative C57BL/6 islet allograft from a chimeric NOD/Lt recipient.

Shown are histologic sections of C57BL/6 islet tissue that had been transplanted into the renal subcapsular space of a chimeric NOD/Lt mouse. The NOD/Lt recipient had developed spontaneous autoimmune diabetes and had been treated with radiation and anti-CD154 mAb and C57BL/6 bone marrow about 4 weeks before islet transplantation (see “Materials and Methods”). This recipient was normoglycemic for 124 days after transplantation and became hyperglycemic immediately after recovery of the kidney bearing the islet tissue shown here. (A) Hematoxylin and eosin–stained section showing normal appearing islet tissue. An inflammatory infiltrate (× 150) was not evident. (B) A frozen section stained immunohistochemically for the presence of the CD3⁺ lymphocytes. There is no appreciable CD3⁺ T-cell infiltrate (× 150). (C, D) Sections stained immunohistochemically for the presence of insulin and glucagon, respectively. Abundant hormone-containing cells are visible (× 150).