Extraneural pathologic prion protein in sporadic Creutzfeldt-Jakob disease.
ABSTRACT BACKGROUND: In patients with sporadic Creutzfeldt-Jakob disease, pathologic disease-associated prion protein (PrPSc) has been identified only in the central nervous system and olfactory-nerve tissue. Understanding the distribution of PrPSc in Creutzfeldt-Jakob disease is important for classification and diagnosis and perhaps even for prevention. METHODS: We used a highly sensitive method of detection--involving the concentration of PrPSc by differential precipitation with sodium phosphotungstic acid, which increased the sensitivity of Western blot analysis by up to three orders of magnitude--to search for PrPSc in extraneural organs of 36 patients with sporadic Creutzfeldt-Jakob disease who died between 1996 and 2002. RESULTS: PrPSc was present in the brain tissue of all patients. In addition, we found PrPSc in 10 of 28 spleen specimens and in 8 of 32 skeletal-muscle samples. Three patients had PrPSc in both spleen and muscle specimens. Patients with extraneural PrPSc had a significantly longer duration of disease and were more likely to have uncommon molecular variants of sporadic Creutzfeldt-Jakob disease than were patients without extraneural PrPSc. CONCLUSIONS: Using sensitive techniques, we identified extraneural deposition of PrPSc in spleen and muscle samples from approximately one third of patients who died with sporadic Creutzfeldt-Jakob disease. Extraneural PrPSc appears to correlate with a long duration of disease.
Article: Immunotherapy in prion disease.[show abstract] [hide abstract]
ABSTRACT: Transmissible spongiform encephalopathies (TSEs), also known as prion diseases, describe a group of fatal neurodegenerative disorders affecting both humans and animals. Accumulation of misfolded prion proteins is the pathological hallmark of these disorders; such accumulation occurs in lymphoreticular tissue prior to CNS involvement in scrapie, experimental models and human variant Creutzfeldt-Jakob disease. Lymphoreticular accumulation of misfolded prion protein has not been demonstrated in human sporadic or genetic forms of TSE. Once clinical symptoms develop, all prion disorders have a rapidly progressive and lethal course, and no effective therapy exists. In the past 10 years, antibody-based immunotherapy has been considered for other neurodegenerative disorders associated with protein misfolding and, therefore, might also be an effective approach to prevention or treatment of prion disease. Self-tolerance to endogenous prion protein is, however, a major challenge to the development of effective immunotherapy, as is the risk of adverse effects from active immunization. This Review summarizes the evidence that immunization could slow disease progression or increase lifespan in animal models of prion diseases. The therapeutic potential of these strategies in treating patients with prion diseases is also discussed.Nature Reviews Neurology 12/2012; · 12.46 Impact Factor
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ABSTRACT: The advent of genomics and proteomics has been a catalyst for the discovery of biomarkers able to discriminate biological processes such as the pathogenesis of complex diseases. Prompt detection of prion diseases is particularly desirable given their transmissibility, which is responsible for a number of human health risks stemming from exogenous sources of prion protein. Diagnosis relies on the ability to detect the biomarker PrP(Sc), a pathological isoform of the host protein PrP(C), which is an essential component of the infectious prion. Immunochemical detection of PrP(Sc) is specific and sensitive enough for antemortem testing of brain tissue, however, this is not the case in accessible biological fluids or for the detection of recently identified novel prions with unique biochemical properties. A complementary approach to the detection of PrP(Sc) itself is to identify alternative, "surrogate" gene or protein biomarkers indicative of disease. Biomarkers are also useful to track the progress of disease, especially important in the assessment of therapies, or to identify individuals "at risk". In this review we provide perspective on current progress and pitfalls in the use of "omics" technologies to screen body fluids and tissues for biomarker discovery in prion diseases.Journal of Biomedicine and Biotechnology 01/2010; 2010:613504. · 2.44 Impact Factor
Article: Mouse senile amyloid fibrils deposited in skeletal muscle exhibit amyloidosis-enhancing activity.[show abstract] [hide abstract]
ABSTRACT: Amyloidosis describes a group of protein folding diseases in which amyloid proteins are abnormally deposited in organs and/or tissues as fine fibrils. Mouse senile amyloidosis is a disorder in which apolipoprotein A-II (apoA-II) deposits as amyloid fibrils (AApoAII) and can be transmitted from one animal to another both by the feces and milk excreted by mice with amyloidosis. Thus, mouse AApoAII amyloidosis has been demonstrated to be a "transmissible disease". In this study, to further characterize the transmissibility of amyloidosis, AApoAII amyloid fibrils were injected into transgenic Apoa2(c)Tg(+/-) and normal R1.P1-Apoa2(c) mice to induce AApoAII systemic amyloidosis. Two months later, AApoAII amyloid deposits were found in the skeletal muscles of amyloid-affected mice, primarily in the blood vessels and in the interstitial tissues surrounding muscle fibers. When amyloid fibrils extracted from the skeletal muscles were subjected to Western blot analysis, apoA-II was detected. Amyloid fibril fractions isolated from the muscles not only demonstrated the structure of amyloid fibrils but could also induce amyloidosis in young mice depending on its fibril conformation. These findings present a possible pathogenesis of amyloidosis: transmission of amyloid fibril conformation through muscle, and shed new light on the etiology involved in amyloid disorders.PLoS Pathogens 05/2010; 6(5):e1000914. · 9.13 Impact Factor