Credit: Qi lab, University of Michigan
The top two images show the pancreas of a normal research mouse, with a wide view at left and a zoomed-in view of the area in the box on the right, showing the insulin-producing islets in lighter purple. The bottom two images show the pancreas of a mouse that lacked two immune-system factors called TLR2 and TLR4; the zoomed-in view shows how large the islets are because of the growth of insulin-producing beta cells inside them.