Prominent Stress Response of Purkinje Cells in Creutzfeldt–Jakob Disease

To examine the role of stress-related 70-kDa heat shock proteins (Hsp-s) in Creutzfeldt–Jakob disease (CJD), we performed immunocytochemistry to detect Hsp-72 and Hsp-73, together with the abnormal (PrP Sc ) and the presumed cellular form (PrP C ) of the prion protein, and TUNEL method to measure cellular vulnerability in different brain regions in CJD and control cases. While Hsp-73 showed uniform distribution in all the examined samples, an increase in the number of Purkinje cells with prominent accumulation of Hsp-72 in the CJD group was observed. These neurons also showed intense PrP C staining, but TUNEL-positive nuclei were only detected in the granular (Hsp-72-negative) cell layer. Fewer cells of the inferior olivary nucleus were immunoreactive for Hsp-72 in CJD than in control cases, and regions showing severe spongiform change and gliosis exhibited fewer Hsp-72-immunoreactive neurons. Our results indicate that accumulation of the inducible Hsp-72 in certain cell types may be part of a cytoprotective mechanism, which includes preservation of proteins like PrP C .