Fig. 2.

Islet histology of spontaneous diabetic NOD mice at recent onset of disease and treatment with AAT (100 days after onset). NOD pancreases are analyzed at onset of diabetes (A and B) and after treatment with AAT (C and D). A and C show pancreases that are immunostained for insulin, and B and D show pancreases that are immunostained for glucagon. (A) At the onset of overt hyperglycemia, most islets are atrophic with few β cells remaining (unstained central cells); even so some islets remain that have substantial number of beta cells and a massive lymphocyte infiltrate. The remaining beta cells are partially degranulated. (B) The same islet stained for glucagon is seen. (C and D) After treatment of diabetic NOD mice as determined by three consecutive pretreatment blood glucose levels of 300–350 mg/dl, islets have similar atrophic appearance with occasional large, β cell-rich islets that are less degranulated and have greater proportion of β to α cells than at onset, and are surrounded, not invaded, by lymphocytes. (Scale bars = 50 μm.)