The lysosomal proteinase cathepsin D has been localized in rabbit skin by immunocytochemical techniques. The enzyme was found in the basal layer of the epidermis, hair follicles, sebaceous glands, fibroblasts, and endothelial cells. An autoradiographic technique, using the Fab' fragment of IgG, was also used for more effective identification of cell types that contain cathepsin D.
Lazarus GS, Poole AR. Immunocytochemical Localization of Cathepsin D in Rabbit Skin. Arch Dermatol. 1975;111(9):1150-1153. doi:10.1001/archderm.1975.01630210066006