Prion neuroinfections represent an emergent problem namely after the epidemic brake out of the bovine spongiform
encephalopathies, which culminated in 1993. Isolated cases can still emerge. The next case was the discovery of
a new variant of Creutzfeldt-Jakob disease in the comparatively young persons with proved alimentary infection
route – about 140 cases has been described. Physiological prions are glycoproteins, affixed to the rafts of cell
membranes (namely in neurons) by glycosylphosphatidylinositol anchor. They act as signalling molecules and
participate in the cooper metabolism. Despite the intensive study in many prestigious laboratories, the way how the
pathogenicis oform of prions, given by the prevalence of beta-conformations in the polypeptide chain develops has
not been proved yet. Pathogenic isoforms are formed intracellulary after the precedent endocytosis. Aggregations
of abnormal prion molecules build up prion amyloid deposits in the form of fibrils or plaques. The loss of neurons
brings about the neurological symptoms, which are not directly related to the amounts of amyloid deposits.
Characteristic findings of spongiosis and the immunohistochemical evidence of protease-resistant prions belong to
the only reliable tests. Reliable intravital test in the blood or urine is not yet available. All forms of human and animal
transmissible spongiform encephalopathies develop only in genetically sensitive individuals. A brief overview of
clinical forms and some biochemical and genetic aspects of the disease are given.
humans and animal forms of transmissible spongiform encephalopathy, prion neuroinfections, CJD,
vCJD, BSE, scrapie, CWD.