Autoantibodies against axonal neurofilaments in patients with Kuru and Creutzfeldt-Jakob disease.

The serums of some patients with subacute spongiform encephalopathies contain an autoantibody in higher titer against a normal fibrillar protein within the axon of mature central neurons in culture. The morphological features of this neurofilament, as demonstrated by immunofluorescence and immunoperoxidase staining, and the partial characterization of the antibody are described. The detection of this hetero-specific autoantibody is the first evidence of an immune reaction in the spongiform encephalopathies.

Infection as the etiology of spongiform encephalopathy (Creutzfeldt-Jakob disease).

Fatal spongiform encephalopathy occurred in four chimpanzees 12 to 14 months after inoculation with suspensions of brain from four patients, respectively. Chimpanzee to chimpanzee transmission was effected without reduction in incubation period. Retransmission of the disease to a second chimpanzee occurred when an inoculum that had been stored at -70 degrees C for over 2 years was used.

Experimental subacute spongiform virus encephalopathies in primates and other laboratory animals.

The host range of subacute spongiform virus encephalopathies is described. The asymptomatic incubation period and the duration of the illnesses in various species of animal hosts is discussed along with information on additional species of Old World and New World monkeys and the domestic cat, which have been shown to be susceptible to subacute spongiform virus encephalopathies.

Measles virus nucleotide sequences: detection by hybridization in situ.

A tritium-labeled probe that detects measles virus nucleotide sequences was hybridized in situ to cells infected with measles virus and to sections of brain tissue from patients with subacute sclerosing panencephalitis and from patients with multiple sclerosis. The measles virus genome was detected in many cells in subacute sclerosing panencephalitis where this virus would have been missed by methods such as immunofluorescence. Measles virus sequences were also found in two foci in one of four cases of multiple sclerosis. This refined method of hybridization in situ, which can be useful in the search for covert virus infections of man, provides evidence that viruses may be involved in multiple sclerosis.

Transmission of experimental kuru to the spider monkey (Ateles geoffreyi).

Clinical signs and pathological changes characteristic of kuru in man and experimental kuru in chimpanzees were observed in two spider monkeys, Ateles geoffreyi, after inoculation with brain tissue from a kuru-affected chimpanzee. The incubation period for one of the monkeys was 23 months, and 26 months for the other.

Spontaneous tranformation of human brain cells grown in vitro and description of associated viurs particles.

A human brain cell culture grown in vitro has spontaneously transformed, as determined by morphology, growth characteristics, and karyotype analysis. Virus particles morphologically akin to oncogenic RNA viruses are present in the transformed cells, which are now in subculture 60.

Creutzfeldt-Jakob disease (spongiform encephalopathy): transmission to the chimpanzee.

Biopsy material taken from the brain of a patient with CreutzfeldtJakob disease with status spongiosus induced a similar fatal encephalopathy in a chimpanzee 13 months after inoculation.

Infection-specific particle from the unconventional slow virus diseases.

Scrapie-associated fibrils, first observed in brains of scrapie-infected mice, were also observed in scrapie-infected hamsters and monkeys, in humans with Creutzfeldt-Jakob disease, and in kuru-infected monkeys. These fibrils were not found in a comprehensive series of control brains from humans and animals affected with central nervous system disorders resulting in histopathologies, ultrastructural features, or disease symptoms similar to those of scrapie, kuru, and Creutzfeldt-Jakob disease. These fibrils are also found in preclinical scrapie and in the spleens of scrapie-infected mice; they are a specific marker for the "unconventional" slow virus diseases, and may be the etiological agent.

Intraneuronal aluminum accumulation in amyotrophic lateral sclerosis and Parkinsonism-dementia of Guam.

Scanning electron microscopy with energy-dispersive x-ray spectrometry was used to analyze the elemental content of neurofibrillary tangle (NFT)-bearing and NFT-free neurons within the Sommer's sector (H1 region) of the hippocampus in Guamanian Chamorros with amyotrophic lateral sclerosis and parkinsonism-dementia and in neurologically normal controls. Preliminary data indicate prominent accumulation of aluminum within the nuclear region and perikaryal cytoplasm of NFT-bearing hippocampal neurons, regardless of the underlying neurological diagnosis. These findings further extend the association between intraneuronal aluminum and NFT formation and support the hypothesis that environmental factors are related to the neurodegenerative changes seen in the Chamorro population.

Antibodies to neurofilament protein in retinitis pigmentosa.

Antibodies reactive with heterologous neural tissue were detected by indirect immunofluorescence microscopy in the sera of 17 of 34 patients with retinitis pigmentosa, one of 30 normal control sera, and a variable percentage of sera derived from subjects with diverse ocular and neurological diseases. These antibodies were also found both in disease-free first degree relatives and in spouses of patients with retinitis pigmentosa. Analytical sodium dodecyl sulfate-polyacrylamide gel electrophoresis of human spinal cord components followed by immunoblots with sera under study revealed that the serum antibody was specific for the high molecular weight protein subunit of neurofilaments. No correlation was found between the presence of these antibodies and other immunological and clinical parameters in retinitis pigmentosa. These findings suggest that release of piled-up neurofilaments from damaged neurones in retinitis pigmentosa triggers B lymphocytes autoreactive to neurofilament antigens.

Sequence analysis of an immunogenic and neutralizing domain of the human T-cell lymphoma/leukemia virus type I gp46 surface membrane protein among various primate T-cell lymphoma/leukemia virus isolates including those from a patient with both HTLV-I-associated myelopathy and adult T-cell leukemia.

Human T-cell lymphoma/leukemia virus type I (HTLV-I) causes adult T-cell leukemia/lymphoma and HTLV-I-associated myelopathy. Specific regions within the outer envelope proteins of other retroviruses, e.g., human immunodeficiency virus type 1, are highly immunogenic and, because of the selective pressure of the host immune system, quite variable. Mutations in the external envelope protein gene of murine retroviruses and human immunodeficiency virus type 1 influence cellular tropism and disease pathogenesis. By contrast, no disease-specific viral mutations have been identified in HTLV-I-infected patients. However, all isolates studied thus far have originated from leukemic cell lines, peripheral blood mononuclear cells, or cerebrospinal fluid lymphocytes from patients with HTLV-I-associated myelopathy and adult T-cell leukemia/lymphoma and, therefore, may not truly reflect tissue-associated variation. The midregion of the HTLV-I gp46 external envelope glycoprotein (amino acids 190-209) induces an antibody response in 90% of infected individuals, and a hexapeptide in this region (amino acids 191-196) elicits antibodies in rabbits which inhibit syncytia formation and infection of target lymphocytes. Because of the above, we expected the neutralizing domain of the gp46 env gene of HTLV-I to possess disease or organ-associated mutations selected by the infected host's immune system. Hence, we amplified, cloned, and sequenced HTLV-I DNA directly from in vivo central nervous system, spleen, and kidney specimens, and a leukemic cell line from a patient (M. J.) with both HTLV-I-associated myelopathy and adult T-cell leukemia/lymphoma to discern the possibility of tissue- and/or disease-specific variants. In addition, we sequenced several HTLV-I isolates from different regions of the world, including Papua New Guinea, Bellona, and Liberia, and compared them to other previously published HTLV-I and related retroviral sequences. The 239-base pair sequence corresponding to amino acids 178 to 256 in gp46 displayed minor tissue-specific variation in clones derived from central nervous system tissues from patient M. J., but overall was highly conserved at both the DNA and amino acid levels. Variation was observed in this region among the other HTLV-I, simian T-cell lymphoma virus type I, and HTLV-II isolates in a pattern that was consistent with their known phylogenetic relationship. No consistent disease-related changes were observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Intracerebral inoculation of experimental animals with brain tissue from patients with schizophrenia. Failure to observe consistent or specific behavioral and neuropathological effects.

To test the possibility that some cases of schizophrenia result from infection with a transmissible slow viral agent, 57 experimental animals (six chimpanzees, 12 Old World monkeys, 17 New World monkeys, and 22 guinea pigs) were inoculated intracerebrally with brain tissue from ten patients and followed up for six years. Behavioral comparisons with control animals revealed no consistent behavioral differences. Histological, immunohistochemical, and morphometric examination of brains of animals that died revealed no specific neuropathological abnormalities. These findings do not support a role for a virus-induced slow infection in the pathogenesis of schizophrenia but must be weighed against methodological limitations in animal susceptibility, disease communicability, and assay sensitivity.

Thermal stability and conformational transitions of scrapie amyloid (prion) protein correlate with infectivity.

The scrapie amyloid (prion) protein (PrP27-30) is the protease-resistant core of a larger precursor (PrPSc) and a component of the infectious scrapie agent; the potential to form amyloid is a result of posttranslational event or conformational abnormality. The conformation, heat stability, and solvent-induced conformational transitions of PrP27-30 were studied in the solid state in films by CD spectroscopy and correlated with the infectivity of rehydrated and equilibrated films. The exposure of PrP27-30 in films to 60 degrees C, 100 degrees C, and 132 degrees C for 30 min did not change the beta-sheet secondary structure; the infectivity slightly diminished at 132 degrees C and correlated with a decreased solubility of PrP27-30 in sodium dodecyl sulfate (SDS), probably due to cross-linking. Exposing PrP27-30 films to formic acid (FA), trifluoroacetic acid (TFA), trifluoroethanol (TFE), hexafluoro-2-propanol (HFIP), and SDS transformed the amide CD band, diminished the mean residue ellipticity of aromatic bands, and inactivated scrapie infectivity. The convex constraint algorithm (CAA) deconvolution of the CD spectra of the solvent-exposed and rehydrated solid state PrP27-30 identified five common spectral components. The loss of infectivity quantitatively correlated with a decreasing proportion of native, beta-pleated sheet-like secondary structure component, an increasing amount of alpha-helical component, and an increasingly disordered tertiary structure. The results demonstrate the unusual thermal stability of the beta-sheet secondary structure of PrP27-30 protein in the solid state. The conformational perturbations of PrP27-30 parallel the changes in infectivity and suggest that the beta-sheet structure plays a key role in the physical stability of scrapie amyloid and in the ability to propagate and replicate scrapie.

Preclinical lesions and their progression in the experimental spongiform encephalopathies (kuru and Creutzfeldt-Jakob disease) in primates.

Creutzfeldt-Jakob disease and kuru were studied in experimental primates. Eight animals with clinical disease lasting from 1/2 to 12 1/2 months were evaluated for histological evidence of progression of the pathological triad of neuronal vacuolation, neuronal loss and fibrous astrocytosis. The first change to appear was neuronal vacuolation, in both the body of neurones and in the neuropil. Fibrous astrocytosis was found subsequent to neuronal damage and necrosis. Neuronal loss was apparent when clinical signs were present. As the clinical disease progressed, so did the severity of neuronal loss and astrocytosis. Five animals, 1 1/2-10 1/2 months after intracerebral inoculation, before they had shown any signs of clinical disease, had histological evidence of neuronal vacuolation and astrocytosis.

Phenotypic variability of Gerstmann-Sträussler-Scheinker disease is associated with prion protein heterogeneity.

Gerstmann-Sträussler-Scheinker disease (GSS), a cerebello-pyramidal syndrome associated with dementia and caused by mutations in the prion protein gene (PRNP), is phenotypically heterogeneous. The molecular mechanisms responsible for such heterogeneity are unknown. Since we hypothesize that prion protein (PrP) heterogeneity may be associated with clinico-pathologic heterogeneity, the aim of this study was to analyze PrP in several GSS variants. Among the pathologic phenotypes of GSS, we recognize those without and with marked spongiform degeneration. In the latter (i.e. a subset of GSS P102L patients) we observed 3 major proteinase-K resistant PrP (PrPres) isoforms of ca. 21-30 kDa, similar to those seen in Creutzfeldt-Jakob disease. In contrast, the 21-30 kDa isoforms were not prominent in GSS variants without spongiform changes, including GSS A117V, GSS D202N, GSS Q212P, GSS Q217R, and 2 cases of GSS P102L. This suggests that spongiform changes in GSS are related to the presence of high levels of these distinct 21-30 kDa isoforms. Variable amounts of smaller, distinct PrPres isoforms of ca. 7-15 kDa were seen in all GSS variants. This suggests that GSS is characterized by the presence PrP isoforms that can be partially cleaved to low molecular weight PrPres peptides.

Transmissible spongiform encephalopathy (Creutzfeldt-Jakob disease). Atypical clinical and pathological findings.

A middle-aged neurosurgeon had an 18-month illness characterized by abnormal sleep patterns, paresthesias, and necrotizing cutaneous lesions with vasculitis and signs of cerebral, brainstem, vestibulocerebellar, and progressive spinal cord involvement. Biopsy specimens of nerve and skin showed an acute vasculitis with endovascular cellular proliferation in the pattern of a Köhlmeier-Degos lesion and focal epidermal necrosis. Mental changes and cranial-nerve signs developed. Myoclonus occurred occasionally during sleep. Akinetic mutism ensued. At autopsy, major abnormalities were limited to the nervous system and skin. Spongiform encephalopathy typical of Creutzfeldt-Jakob disease was found with amyloid kuru plaques. A cribriform change distinct from the spongiform change was seen focally in the white matter. Scarred skin lesions and a healed, partially obliterative arteritis were noted. Inoculation of brain and lung into nonhuman primates resulted in a spongiform encephalopathy.

HTLV-I DNA sequences in CNS tissue of a patient with tropical spastic paraparesis and HTLV-I-associated myelopathy.

Human T cell lymphotrophic virus type I (HTLV-I) is the etiologic agent of adult T cell lymphoma/leukemia (ATLL) and tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). We studied an HTLV-I-seropositive, white man diagnosed in 1977 with ATLL and 10 years later, 6 months prior to his death, with TSP/HAM. Sections of brain, spinal cord, and visceral tissues were examined histologically, immunohistochemically, by in situ hybridization, and by the polymerase chain reaction (PCR). PCR amplification of a region of the polymerase (pol) gene of HTLV-I from visceral tissue demonstrated the presence of proviral HTLV-I DNA in paraffin-embedded sections from the liver and in DNA extracted from frozen sections of kidney and spleen, but failed to demonstrate viral sequences in paraffin sections of the lung and a lymph node. PCR analysis of CNS tissue demonstrated viral sequences in regions of the brain including frozen samples from cerebellum and cerebral cortex and paraffin sections of the thoracic spinal cord, but failed to detect proviral DNA in sections from a region in the lumbar cord. These results map the distribution of HTLV-I DNA sequences in the CNS of a patient with TSP/HAM for 3 months.

Attempts to implicate viruses in myasthenia gravis.

We investigated the hypothesis that a persistent viral infection of the thymus gland might trigger the autoimmune disease myasthenia gravis (MG). Thymus glands of nine patients with recent onset of MG were studied by a variety of techniques to detect the presence of occult viruses. No evidence of viral infection was found.

Brain destruction alone does not elevate brain aluminum.

Graphite furnace atomic-absorption spectroscopy was used to measure aluminum concentrations in brain samples from 33 patients dying from a variety of neurologic diseases. Four samples from patients dying of nonneurologic causes also were studied. Nine samples (one from each of nine patients) of Creutzfeldt-Jakob disease brain contained normal amounts of aluminum. Aluminum was increased in 9 of 18 brain specimens with seven different pathologic processes. This included three of seven Alzheimer disease, two of three Huntington disease, two of two Parkinson disease, one of one progressive supranuclear palsy, one of one acoustic neuroma, one of two cerebrovascular disease, and one of two Guamanian amyotrophic lateral sclerosis (ALS). Aluminum was normal in the remaining samples (four normal, two ALS, one multiple sclerosis, one Pick disease, and two Guamanian parkinsonism-dementia). The significance of high aluminum values is not clear, but the normal values from the Creutzfeldt-Jakob cases imply that neuronal destruction per se need not lead to accumulation of aluminum in the brain.

Coexistence of Creutzfeldt-Jakob disease and Alzheimer's disease in the same patient.

We report the case of a 73-year-old patient in whom a diagnosis of Creutzfeldt-Jakob disease, suggested by the clinical course, was verified by the neuropathologic finding of widespread spongiform change and astrogliosis, the presence of proteinase-resistant protein in brain extracts, and the experimental transmission of spongiform encephalopathy to primates inoculated with brain tissue. However, neuropathologic examination also revealed a profusion of senile and neuritic plaques and neurofibrillary tangles that reacted with antibody to the amyloid beta-protein characteristic of Alzheimer's disease, but not with antibody to the scrapie amyloid protein characteristic of Creutzfeldt-Jakob disease.