ME7-infected spleens at end-stage prion disease have larger FDC networks in germinal centers. Confocal images of ME7-infected mouse spleen sections 200 days after ME7 infection. Immunofluorescent staining indicates IgM (red), CD3 (blue), and FDC (green). (A, B, and C) Low-power confocal images of germinal centers. Scale bar represents 100 μm. (D) High-power confocal images of the area boxed in white in (C). Scale bar, 25 μm. N = 6 control and 6 ME7-infected mice.