Editorial [Hot Topic: New and Emerging Approaches to Prion Diseases (Guest Editor: Akikazu Sakudo)]

Recently, several detection methods for prion and/or prion protein (PrP) (including abnormal and cellular PrP) have been developed. An important method is protein misfolding cyclic amplification (PMCA), which enables the amplification of abnormal PrP in vitro. Prospects for therapy or preventative vaccine have also been explored. Accumulated knowledge on the role of cellular PrP would provide useful information for exploring strategies for the treatment of prion diseases. To discuss this hot topic, scientists using various approaches to study the pathogenesis, diagnosis, and prevention of prion diseases were invited. I am glad to have the honor to organize a Hot Topic issue for Protein and Peptide Letters and to experience working with eminent scientists to review research on prion diseases. This issue covers the broad topic of prion biology and includes articles on the following topics: fundamental knowledge and possible pathogenesis of prion diseases written by myself and Prof. Kazuyoshi Ikuta, recent studies on a neurocytotoxicity model of a PrP-derived peptide written by Dr. Neville Vassallo, the role of cellular PrP in functions of macrophage and dendritic cells written by Prof. Takashi Onodera and colleagues, uptake of abnormal PrP in the intestines written by Prof. Hiroyuki Nakayama and colleagues, abnormal PrP amplification by PMCA written by Dr. Ryuichiro Atarashi, prospects for preventative vaccine against prion diseases written by Prof. Suehiro Sakaguchi, and yeast prions written by Dr. Yuji Inoue. Hopefully, readers will enjoy this issue, obtain useful information for their own research, and be inspired with new ideas for future research on prion biology.