Mice were anesthetized before sacrifice and then perfused with ice-cold phosphate-buffered saline (PBS) followed by 4% paraformaldehyde (PFA). The brain and spinal cord were dissected, fixed in 2% PFA overnight, dehydrated in 25% sucrose at 4 °C, embedded in OCT (Leica, 14020108926) and processed for cryo-sections at 12 μm. Cultured cells were briefly fixed with a chilled 4% PFA/PBS solution for 10 min and permeabilized with 0.4% Triton X-100/PBS for 10 min on ice. For immunohistochemistry, cryo-sections were permeabilized and blocked in blocking buffer (0.4% Triton X-100 and 3% BSA in PBS) for 30 min at room temperature (RT) and overlaid with diluted primary antibodies overnight at 4 °C. After washing with PBS, sections were incubated with secondary antibodies conjugated to Cy2, Cy3 and Cy5 (Jackson ImmunoResearch Laboratories, 1:1000) and DAPI (Thermo Fisher Scientific, Cat#D1306) for 1 h at RT, washed three times in PBS and then mounted with Mounting medium. For Immunocytochemistry, Cultured cells were briefly fixed with a 4% PFA/PBS solution for 10 min at RT, permeabilized and blocked by the pre-cold buffer (0.4% Triton X-100 and 3%
