Figure 1: Representative H&E stained histological sections of the pancreases (a) and histopathological scores of the pancreases (b) in poly I:C-treated MRL/Mp mice in the 5 different age groups. The group of 10-week-old mice showed mononuclear cell aggregation and infiltration within the interstitium, and no pancreatic parenchymal destruction (grade 1). The group of 14-week-old mice showed focal parenchymal destruction with mononuclear cell infiltration in the pancreases (grade 2). The group of 16-week-old mice showed diffuse parenchymal destruction, but some parenchymal residue was retained intact in the pancreases (grade 3). The groups of 18- and 20-week-old mice showed that almost all pancreatic tissue, except for the pancreatic islets, was destroyed or replaced with fibrosis or adipose tissue (grade 4). The control mice were no significant change (grade 0). Poly I:C-treated MRL/Mp mice (A)–(E), controls (F). ×100 magnification (large panel), ×400(inset). Data are expressed as .