Provides an authoritative source on recent research in the study of prions, which are implicated in spongiform encephalopthies such as kuru and bovine encephalopathy. Early chapters provide an introduction to prion biology, record the development of the prion concept, describe bioassays for prions, explain basic principles of prion replication, and outline some methods for study of prions. Remaining chapters cover topics ranging from the cell biology of prions, to transgenic and gene-targeted mice, to inherited and infectious prion diseases of humans. Other subjects include fungal prions, biocontainment, and mammalian prion strains.