Immunohistochemical localization of 14.3.3 ζ protein in amyloid plaques in human spongiform encephalopathies

Abstract.

The localization of 14.3.3 proteins was studied in different subtypes of brain amyloid plaques. We examined paraffin-embedded brain sections of sporadic MV2 Creutzfeldt-Jakob disease (sCJD) with Kuru plaques, sporadic VV2 CJD with plaque-like PrP^sc (the abnornal form of prion protein) deposits, variant CJD (vCJD) with florid plaques, Gerstmann-Straüssler-Scheinker (GSS) with multicentric plaques and of Alzheimer's disease (AD) with senile plaques. Adjacent immunostaining revealed PrP^sc and 14.3.3 ζ deposits in the same amyloid plaques in all cases of sporadic CJD and vCJD, whereas 14.3.3 ζ was not seen in amyloid plaques of GSS with A117V, P102L and D202N mutations. The same immunostaining method using anti-βA4 and anti-14.3.3 ζ antibodies revealed no colocalization in patients with AD. Our data suggest that 14.3.3 ζ protein could interact either with PrP or with other components of PrP^sc deposits in CJD.