CNS ceroid accumulation is not responsible for death of CtsD−/− mice. Representative brain sections from CtsD−/− mouse injected with AAV-CtsD bilaterally into CNS and presenting with a completely moribund phenotype at day p62 are shown in A, C, E, G, and I, whereas contralateral brain sections from a CtsD−/− mouse injected with AAV-CtsD unilaterally into CNS and additionally into periphery presenting with a healthy phenotype at p133 is shown in B, D, F, H, and J. Note that J was taken from a more rostral part of the cerebellum as compared with I. Pictures are overlays of wide field micrographs showing ceroid autofluorescence in green, activated microglia stained by MCA711 in red, and nuclear counter stain by DAPI in blue.