Tubulovesicular structures in human and experimental Creutzfeldt-Jakob disease

Tubulovesicular structures (TVS) have been consistently observed in brain tissue of animals with transmissible spongiform encephalopathies such as natural and experimental scrapie, bovine spongiform encephalopathy, and experimental Creutzfeldt-Jakob disease (CJD). In this communication we demonstrate for the first time the presence of TVS in natural CJD. TVS were detected in all 3 CJD specimens. However, they were rare and were found only in one or two locations per grid. They were seen in distended pre- and postsynaptic terminals and measured approximately 35 nm in diameter, and they were smaller and of higher electron density than synaptic vesicles. Their occurrence in all types of spongiform encephalopathies irrespective of the affected host and the strain of infectious agent emphasizes their biological significance.