Fig. 1

Characteristic histopathological features in the reported sCJD cases. Prominent spongiform change is observed in HE-stained sections in the frontal cortex (A1, a1 higher magnification), striatum (B1, b1 higher magnification), parahippocampal region (C1, c1 higher magnification), and occipital cortex (E1, e3 higher magnification). Ballooned neurons are observed in severely affected brain areas (c1, arrow inset). There is a striking dissociation between the marked spongiform change and the very faint deposition of pathological prion protein (PrP) by immunohistochemistry (anti-PrP antibody 12F10) in the frontal cortex (A2, a2 higher magnification), striatum (B2, b2 higher magnification), parahippocampal region (C2, c2 higher magnification) and in most areas of the occipital cortex (E2, e4 higher magnification). There are focal areas (square in E2) with coarse patchy-like PrP deposits (e1, e2). In the cerebellum (D1), spongiform change is focally prominent in the molecular layer (d1), and also here, there is a dissociation between the rather severe spongiform change and the mild PrP deposits (D2, d2 left, higher magnification). Focally, deposits appear coarser and patchy (d2, right panel). Scale bars: 10 μm: c1 inset, a2, b2, c2, e3, e4; 20 μm: a1, b1, c1, d2, e2; 50 μm: d1, e1; 500 μm: A1, A2, B1, B2; 1,2 mm: C1, C2, D1, D2, E1, E2. Panels A1, A2, B1, B2, C1, C2, E1, E2 correspond to patient 1 and panels D1, D2 to patient 2