Protease resistant prion proteins are not present in sporadic "poor outcome" schizophrenia.

Various clinical and epidemiological data have suggested the possibility of infectious mechanisms in schizophrenia. In addition, lengthy prodromal psychiatric symptoms can presage the development of Creutzfeldt-Jakob disease, a prototypical prion disorder. Accordingly, the presence of human protease resistant prion proteins (PrPres) was assessed in postmortem frontal cortical and thalamic tissues from a prospectively accrued and well characterised sample of elderly patients with chronic, sporadic, "poor outcome" schizophrenia using a sensitive immunoblot assay. No PrPres was found in the brains of any of the cases, providing evidence against a role for abnormal prion proteins in the pathogenesis of schizophrenia.