Representative immunohistochemistry of enzymes involved in glucosylsphingosine metabolism between control and glaucomatous human ON. ON sections (10 μm) were subjected to immunohistochemical analysis using primary and secondary antibodies as indicated. (A) Anti-ASAH1, probed with Alexa 647 goat anti-rabbit, (B) anti-ASAH2, Alexa 647 goat anti-rabbit, (C) anti-GBA, probed with Cy5-conjugated goat anti-rabbit, and (D) anti-GBA2, probed with Alexa 647 goat anti-rabbit. In each 4′,6-diamidino-2-phenylindole (DAPI) (blue) nucleus, stained image and merged image have been presented as indicated. Bar = 100 μm. Age and sex of (all Caucasian donors; Supplementary Table S1) are as indicated on each merged image.