Fig. 1

Superificial white matter compartments and white matter NPFF-immunopositive cells in a control case. a Detail showing gray matter (GM) und white matter (WM), including the superficial white matter compartments I bis V (broken lines) and deep white matter. Each white matter compartment is 500 µm in thickness. Scale bar in b is also valid for a. b Gyral crown of frontal gyrus. The density of the NPFF cells in the white matter increases with increasing proximity to the gyral crown. c–f Polymorph appearances of white matter NPFF-positive cells from the frontal gyrus; pyramidal-like (triangular-shaped) in c and f (see also Fig. 2f), multipolar d, and bipolar/fusiform e Scale bar in c also applies to d–f. a–f Case 8: male, 83 years of age (see also Suppl. Figure 1). Pigment (aldehyde fuchsin) staining plus NPFF-immunohistochemistry (brown chromogen 3,3’-diaminobenzidine tetrahydrochloride, DAB) in 100 µm polyethylene glycol-embedded (PEG) sections