Immunohistochemical test for anti-cathepsin B antibody was performed in transversal spine sections. (A) Spine section stained with toluidin-fuchsin. (B) Spine section incubated with anti-cathepsin B. (C and D) zoomed images, corresponding to A and B, respectively. It is possible to observe the positive (brownish staining) along the decalcified matrix (B), in the same location where cells were observed in the sections stained by toluidine-fuchsin (A).