ABSTRACT
Transmissible spongiform encephalopathies (TSE) are fatal neurodegenerative disorders that are well defined at clinical, pathological and biochemical levels. A most original aspect is the implication of the host cellular ‘prion’ protein (PrPc), which adopts abnormal conformations (PrPsc) that seem to participate in the transmissibility of TSE. Natural prion diseases may have distinct aetiologies. Hereditary forms of Creutzfeldt-Jakob disease and related diseases are described, with dominant autosomal transmission; in all cases there is a mutation of the gene that encodes PrP. The strikingly long incubation period of TSE is featured by prion accumulation in secondary lymphoid organs, where infectivity titers increase before they become detectable in the central nervous system. Identifying all the actors involved in the transport of prions and studying their actual implication in neuro-invasion, will help designing preventive strategies applicable at the pre-clinical stages of TSE.
