Tubulovesicular structures are a consistent (and unexplained) finding in the brains of humans with prion diseases.

Creutzfeldt-Jakob disease (CJD), Gerstmann-Sträussler-Scheinker disease (GSS) and Fatal Familial Insomnia (FFI) are slow neurodegenerative disorders classified as transmissible spongiform encephalopathies (TSEs) or prion diseases, which appear in sporadic, hereditary or environmentally acquired forms. Tubulovesicular structures (TVS) are ultrastructural particles of unknown origin and chemical composition found in the brains of both animal and human forms of transmissible spongiform encephalopathies or prion diseases. In this paper, we report the results of a search for TVS in a total of 13 cases of sporadic Creutzfeldt-Jakob disease, three cases of Gerstmann-Sträussler-Scheinker disease, two cases of Fatal Familial Insomnia, and individual cases of familial, iatrogenic, and variant CJD (vCJD). TVS were found in all but one sporadic and one familial case of CJD. As controls, we examined 15 cases of Alzheimer's disease (AD), two cases of Pick's disease, and one case of multiple system atrophy. TVS were not present in any of these cases. This study confirms the TSE-specificity of TVS, the morphology of which suggests a possible pathogenetic role and relationship to recently described virion-like arrays of 25nm particles in scrapie-infected tissue cultures.

Variations of the ultrastructure of neuronal lipofuscin during childhood and adolescence in the human Ammon's horn.

The ultrastructure of lipofuscin (Lf) was studied in hippocampal and neocortical neurons of children and youngsters between 3 months and 24 years of age. As a standard, regions CA1 and CA4 of Ammon's horn and the gyrus centralis anterior of the left hemisphere were examined, and the ratio of the two components of Lf, the pigment part, and the usually droplet-like lipid part was looked at. Few and small granules with typical linear structures in the pigment part and little lipid droplets were found as early as at the age of 3 months in all brain regions. There were no morphological differences of Lf in the areas of Ammon's horn up to 3 years, but the Lf ultrastructure in Ammon's horn differed clearly from that in the neocortical region. Differences of Lf between the areas CA1 and CA4 were found to appear at the age of 6-8 years, to have a rather variable pattern between age 11 and about 20 years, and to be relatively constant thereafter. The Lf pigment part consisted of irregularly arranged three laminar linear structures. Some varieties could be seen in the size and shape of the Lf granules and in the lipid/pigment ratio. As to the question of Lf being an "age pigment," the findings that the number of Lf granules did not further increase after the period of early adolescence was not consistent with the age pigment hypothesis. No regional or age-dependent differences were found in the Lf of astro- and oligodendroglia.

Clinical and molecular genetic study of a large German kindred with Gerstmann-Sträussler-Scheinker syndrome.

We have verified, by full open reading frame sequencing, the presence of an amino-acid-altering mutation in codon 102 of the scrapie amyloid protein gene in three affected members of a large and well-documented German family with experimentally transmitted Gerstmann-Sträussler-Scheinker syndrome. In addition, we identified the mutation by partial sequencing or DNA restriction enzyme analysis in three of 12 presently healthy family members with an affected parent, and none of 12 members without an affected parent. Thus, a total of six of 15 family members at risk for the disease (including the three established cases) had the same codon 102 mutation, a proportion consistent with the autosomal dominant inheritance pattern of disease expression. It is undetermined whether the mutation influences susceptibility to infection by an exogenous agent or is itself a proximate cause of disease.

Gerstmann-Sträussler-Scheinker disease- the dilemma of molecular and clinical correlations.

Gerstmann-Sträussler-Scheinker disease (GSSD) is a hereditary as well as transmissible human prion disease, restricted to families carrying point mutations of the PRPN gene on chromosome 20. To date 7 different causative mutations have been found. In this review the results of molecular biology with regard to the clinical course are discussed. As the findings of the disorder are very variable, the clinical picture and the neuropathology are extensively reported. An attempt has been made to define the disease, and filter out atypical non-GSSD cases. Finally, a comprehensive bibliography and tabulation of cases reported in the Western and Japanese literature are provided.

Gerstmann-Sträussler-Scheinker disease with A117V mutation in a second French-Alsatian family.

We report a kindred of French/Alsatian origin with symptoms of Gerstmann-Sträussler-Scheinker disease over 3 generations. In the propositus, cerebellar signs and memory disturbance were the presenting features, followed by other neurological manifestations. Biopsy of the cerebral cortex showed numerous multicentric and "kuru"-type amyloid plaques that on immuno-light and electron microscopy stained with antibody to prion protein. Molecular genetic analysis revealed an A117V mutation in the open reading frame of the prion protein gene. Questions as to pathology and spread of this mutation are discussed.

Ultrastructural heterogeneity of neuronal lipofuscin in the normal human cerebral cortex.

The ultrastructure of the age pigment in neurons of the normal human isocortex was investigated in seven autopsies and two biopsies. In the autopsies four cortical areas of Brodmann, viz. 6, 7, 11 and 17 were studied. The lipofuscin granules appear as complexes composed of lipid and pigment. These are characterized by their shape, frequency per neuron, the relative amount of pigment and lipid in the complexes, and the structure of the matrix. The neurons contain numerous varieties of lipopigment, six of which occur with great frequency and are designated as varieties 1-6. Variety 1 is found in pyramidal neurons and seems to be characteristic of long loop projectory neuronal systems. 2 is found in large non-pyramidal neurons. 3 is found in pyramidal and non-pyramidal neurons. 4, 5 and 6 are found in non-pyramidal neurons. The pigment matrix is linear in all six varieties of lipopigment. Short linear elements are present in varieties 1, 2 and 5. Long linear elements are found in varieties 3, 4, and 6. Circular whorled arrangements are found in 4. We think that these varieties of lipofuscin may signify metabolic and/or functional differences of the different types of neurons and may contribute to the biochemical classification of cortical neurons.

[Subacute spongiform encephalopathy with multiform plaque formation. "Peculiar familial-hereditary disease of CNS [spinocerebellar atrophy with dementia, plaques, and plaque-like deposits in cerebellum and cerebrum" (Gerstmann, Sträussler, Scheinker)] (author's transl)]. / Subakute spongiforme Encephalopathie mit multiformer Plaquebildung. "Eigenartige familiär-hereditäre Krankheit des Zentralnervensystems [spino-cerebellare Atrophie mit Demenz, Plaques und plaqueähnlichen Ablagerungen im Klein- und Grossirn" (Gerstmann, Sträussler, Scheinker)].

Report of two unrelated cases of a rare familiar disease of degenerative nature, from a clinical point of view belonging to the spinocerebellar atrophies, combined with dementia. According to the pedigrees, the disease can be followed up to 3--4 generations. Microscopic study reveals glioneuronal dystrophy with spongiform changes together with kuru plaques and atypical plaque-like formations, hitherto only described in this disease. Nosological aspects of these findings are discussed.

Neuronal autophagy in experimental scrapie.

In this study we report the formation of giant autophagic vacuoles (AV) in neurons in experimental scrapie in hamsters. Autophagy is an important step in the cellular turnover of proteins and organelles. It is known to occur in neurons under physiological as under pathological conditions. Giant AV, however, are seen very rarely only in pathological states. In our model AV are much more numerous after intracerebral (i.c.) transmission of the scrapie agent than after the transmission via the intraperitoneal route which points to a correlation between the intensity of the process and the period of incubation. As the appearance of the AV in our model is correlated chronologically with that of scrapie-associated fibrils, at least after i.c. transmission, the process may be related to a disturbance of cellular protein metabolism and, thus, to the processing of prion protein.

Miniplaques and shapeless cerebral amyloid deposits in a case of Gerstmann-Sträussler-Scheinker's syndrome.

Multicentric plaques of typical pathomorphology have been described in two members of the well-documented German family "Sch" with Gerstmann-Sträussler-Scheinker's syndrome (GSS). The case of a third affected member with a clinical course of 10 years is now reported. In addition to multicentric plaques, small granules of prion protein (PrP) with stellate ultrastructure (miniplaques) were found in the tractus perforans and alveus of the hippocampal area. At the ultrastructural level, shapeless amyloid deposits of irregularly arranged bundles of amyloid fibrils were also observed in the same region. All amyloid precipitates apparent at the light microscopic level immunostained for PrP. These observations widen the known spectrum of amyloid plaque morphology in GSS. The multicentric plaque should still, however, be considered the diagnostic hallmark of this disease.

Neuronal autophagy in experimental Creutzfeldt-Jakob's disease.

We report an experimental model of Creutzfeldt-Jakob's disease (CJD) in mice leading to the formation of giant autophagic vacuoles (AV) in neurons of the cerebral cortex. These AV appear at the end of the incubation period (4-6 months postinoculation), together with spongy changes and clinical symptoms. Autophagy, a process of intracellular digestion of cell constituents by the lysosomal compartment, is known in many cell types, where it plays a role both in the physiological turnover and in pathological processes and is involved in protein metabolism. The same also occurs in neurons. Here autophagy is known to occur in the normal state and leads to residual bodies called lipofuscin granules. An increase in lipofuscin is known to occur in human and experimental CJD. Therefore, an increase in autophagy and in AV can be expected. In our experimental model, the activation of neuronal autophagy may be related to an alteration in neuronal protein metabolism.

Gerstmann-Sträussler-Scheinker's disease. Electron-microscopic observations on a brain biopsy.

Light and electron microscopic observations are reported on a brain biopsy of a man of 59 with a rare familial disease of the CNS and a 5-year clinical course. Electron micrographs of the frontal biopsy reveal plaque-like deposits composed of amyloid cores, often multicentric in the cortex and subcortical white matter. They are localized between enlarged astrocytic processes. In the neuropil they are sometimes associated with abnormal neuritic processes, in the white matter with processes of fibrous astroglia and basement membranes. There are no signs of primary neuritic or synaptic involvement in the plaque formation which is more obviously associated with altered astrocytic processes. Moreover, degenerative alterations in the cortical vessels and slight astroglial spongiform changes as well as oligodendroglial proliferation can be found. Plaques are considered to be mainly of the kuru type; the relationship with transmissible spongiform encephalopathies is discussed.

Species-specific ultrastructure of neuronal lipofuscin in hippocampus and neocortex of subhuman mammals and humans.

Lipofuscin represents an integral part of neurons and glial cells in mammals and in submammalian species. It is a special lysosomal organelle, takes part of cellular metabolism, and is a structural expression of catabolic pathways. Species-specific differences of lipofuscin indicate metabolic differences of the relevant neurons. The authors have studied the ultrastructure of neuronal lipofuscin in the hippocampus and cerebral neocortex of dogs, horses, cows, elephants, rats, mice, apes, and humans to answer the question of species-specific differences of this organelle. Paraffin sections of formalin-fixed material were investigated by hematoxylin-eosin and PAS staining, by fluorescence microscopy for autofluorescence, with a laser scanning confocal microscope and by electron microscopy. In the animals studied and in humans the lipofuscin displayed, in addition to the general trilaminar substructure, species-specific appearances. No differences were found in the lipofuscin structure between neocortical and hippocampal neurons of the separate animal species. In contrast, in humans, neurons of the hippocampus showed a particular lipofuscin structure, not only different from the neocortical one, but also with differences between CA1 and CA3/4 sectors. Interestingly, in apes a transitional situation was found with slight differences between neocortical and hippocampal lipofuscin, especially in the rhesus monkey. This peculiarity was corroborated by the distribution of special pentilaminar linear structures in the lipofuscin pigment in all animals, only sparsely in the rhesus monkey and not in humans. The results indicate that lipofuscin ultrastructure of neocortical and hippocampal neurons is species specific and that lipofuscin in the human hippocampal neurons displays structures characteristic of man differing from the neocortical neuronal lipofuscin. The neuronal lipofuscin of apes, especially of the rhesus monkey displays structures in between humans and lower mammals. Nothing is known about the functional significance of these findings. They may indicate metabolic and/or functional characteristics of the relevant neurons.

Experimental transmission of human subacute spongiform encephalopathy to small rodents. IV. Positive transmission from a typical case of Gerstmann-Sträussler-Scheinker's disease.

Spongiform encephalopathy was transmitted to mice from a patient belonging to the "Sch" family with Gerstmann-Sträussler-Scheinker's disease (GSS). Incubation periods in the first passage were much shorter than those in mice infected with Creutzfeldt-Jakob disease. Clinical and pathologic findings of mice infected with both diseases were almost identical. This is the first successful transmission from a typical GSS case without severe spongiform change which suggests the possible transmissible nature of this disorder.

Acid phosphatase activity in human neuronal and glial lipofuscin.

The ultrastructural demonstration of acid phosphatase activity in neuronal and glial lipofuscin of the aged human brain indicates lysosomal activity. Contrary to the constantly high enzyme activity of astroglial lipofuscin and low activity of oligodendroglial lipofuscin, the enzyme activity of neuronal pigment differs in different locations, i.e., in different neuronal populations. The activity is probably based on the importation of lysosomal enzymes into the pigment component of lipofuscin. These facts indicate the possibility of a continuous autophagosomal function of lipofuscin in neuronal and glial cell physiology. Therefore, the findings are arguments against the view that lipofuscin is a wear-and-tear material only and claim for it an active role in cell metabolism.

[Morbus Gerstmann-Sträussler-Scheinker. The Sch. family-a report of three cases (author's transl)]. / Morbus Gerstmann-Sträussler-Scheinker. Familie Sch. - Ein Bericht über drei Kranke.

The clinical symptoms from three cases and histological findings from two patients suffering from morbus Gerstmann-Sträussler-Scheinker (M-GSS) are reported. This disease belongs to the group of subacute spongiform encephalopathies. It is extremely rare and so far has only been observed in 52 members of four large families, in which the symptoms begin between the age of 33 and 50 and lead to death in 4-5 years. In the family reported here, cerebellar symptoms including myoclonia and later dementia, bulbar, and pyramidal symptoms were typical; two patients also had deterioration of vision and hearing. CSF and other biochemical data were normal. The EEGs showed progressive general slowing without periodic dysrhythmia. Evoked potential gave no evidence of demyelinization. The disease may safely be distinguished from morbus Creutzfeldt-Jakob (M-CJ) and Alzheimer's disease by histology, which reveals kuru plaques in most cases and invariably multicentric plaques as well as cortical spongiform changes of varying degree with loss of nerve cells and glial proliferation; however, only minor degenerative alterations in the cortical vessels are seen. The transmission to monkeys and histological similarities to M-CJ and kuru suggest a slow virus related to that causing scrapie. Alternatively, the genetically determined susceptibility of the patient may decide the type of reaction to the slow virus. The disposition to M-GSS is autosomally dominant.

[Basilar or vertebral artery aneurysm as a cause of presumed cervical spine injury (author's transl)]. / Basilaris-Vertebralis-Aneurysmen als Ursache scheinbarer Halswirbelsäulensyndrome. Klinische und morphologische Untersuchungen an fünf klinisch nicht diagnostizierten Fällen.

The characteristic clinical features and morphological findings of five cases of (clinically not diagnosed) fusiform aneurysm of the basilar or vertebral arteries were recurring attacks of positional occipital headache, pain and stiffness in the neck, cranial nerve disturbances, expecially oculomotor palsies and anisokoria, nystagmus, attacks of nausea, vomiting and sweating, tachycardia, pyramidal tract symptoms, and pareses. Severe hypertension had been present in four instances. The aneurysm, which is usually thrombosed, pressed against the pons and medulla oblongata as a space-occupying mass. In addition to hypertension and atheromatosis, congenital defect in the arterial wall are probably significant causative factor. To mistake an aneurysm for a cervical syndrome may be fatal to the patient.

Creutzfeldt-Jakob disease with amyloid angiopathy: diagnosis by immunological analyses and transmission experiments.

It was difficult to make a definite pathological diagnosis in a 73-year-old man with Creutzfeldt-Jakob disease (CJD) due to extensive amyloid angiopathy which lacked any severe spongiform changes. Immunostaining using anti-prion protein (PrP) antibody revealed fine granular deposits in the gray matter, after hydrolytic autoclaving pretreatment on tissue sections. Western blotting also revealed an abnormal isoform of PrP, but PrP gene analysis did not show any abnormalities. The primary transmission experiments were repeated three times and induced spongiform encephalopathy in a few mice after a long incubation period.

Immunogold light and electron microscopic detection of amyloid plaques in transmissible spongiform encephalopathies.

The antigenicity of the 'prion' protein amyloid fibrils was shown to be preserved after glutaraldehyde/OsO4 fixation in uranyl acetate-stained brain tissue blocks from patients with Gerstmann-Sträussler syndrome (GSS) and from mice infected with Creutzfeldt-Jakob disease (CJD). Amyloid plaques were demonstrated by light microscopy in immunogold silver-intensified semithin sections. Under the electron microscope, the amyloid fibrils were labelled in immunogold-reacted ultrathin sections using an antiserum prepared against GSS amyloid plaque cores and mouse amyloid fibrils respectively. The influence of various oxidizing agents (hydrogen peroxide, sodium metaperiodate) on the tissue preservation and the immunohistochemical detection was tested.

Microglia is a component of the prion protein amyloid plaque in the Gerstmann-Sträussler-Scheinker syndrome.

The microglial cell has been demonstrated as component of the cerebral amyloid plaque of Alzheimer's disease. Involvement of microglia in plaques of another cerebral amyloidosis, the Gerstmann-Sträussler-Scheinker syndrome (GSS), has found little attention. We examine here the presence of microglia in GSS plaques by immunohistochemistry and transmission electron microscopy. Paraffin sections from five brains of patients with GSS were immunolabelled with antibodies against prion protein, A4/beta amyloid protein, ferritin, leukocyte common antigen, HLA-DR, CD 68, and the MAC387 epitope for microglia and monocytes/macrophages; microglia was also labelled with the Ricinus communis agglutinin-1 lectin. Such (immuno)labelling demonstrated many delicate cell processes and occasional somata within and around prion protein plaques in all GSS brains. Microglial immunoreactivity was strongest with anti-ferritin and variable with anti-macrophage antibodies. Ultrastructural examination of brain tissue from one autopsy and one biopsy of GSS identified microglial cells in close proximity of amyloid plaque fibrils. Our observations demonstrate microglia as an important component of the amyloid plaque in GSS and suggest a major role for microglia in processing and deposition, or at least organization, of prion protein amyloid. Thus, plaques in both transmissible and non-transmissible cerebral amyloidoses seem to develop via similar pathogenetic mechanisms, irrespective of differences in etiology and molecular composition of the amyloid.

Creutzfeldt-Jakob disease and kuru patients lack a mutation consistently found in the Gerstmann-Sträussler-Scheinker syndrome.

We and others have recently reported that patients with the Gerstmann-Sträussler-Scheinker syndrome have a mutation at codon 102 of the gene coding for amyloid protein that accumulates in this disease. We report here that this mutation was not found in 5 familial and 27 sporadic cases of Creutzfeldt-Jakob disease or in 3 patients with kuru, so that although this mutation may be responsible for amyloidogenesis and transmissibility in Gerstmann-Sträussler-Scheinker syndrome, it cannot be the only cause of human spongiform encephalopathy.