HEXB and Gliosis: Gliosis derived from activation and proliferation of microglia and astrocytes of 16-week-old Hexb−/− mice could be reduced by suppressing autoantibody-mediated immune responses by deleting Fcrγ. Thus, to determine the time of gliosis, activation states of microglia and astrocytes were analyzed at 2–4 weeks of age by immunostaining.