S B Prusiner

University of California, San Francisco, San Francisco, California, United States

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Publications (573)4947.53 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Prions are proteins that adopt alternative conformations that become self-propagating; the PrP(Sc) prion causes the rare human disorder Creutzfeldt-Jakob disease (CJD). We report here that multiple system atrophy (MSA) is caused by a different human prion composed of the α-synuclein protein. MSA is a slowly evolving disorder characterized by progressive loss of autonomic nervous system function and often signs of parkinsonism; the neuropathological hallmark of MSA is glial cytoplasmic inclusions consisting of filaments of α-synuclein. To determine whether human α-synuclein forms prions, we examined 14 human brain homogenates for transmission to cultured human embryonic kidney (HEK) cells expressing full-length, mutant human α-synuclein fused to yellow fluorescent protein (α-syn140*A53T-YFP) and TgM83(+/-) mice expressing α-synuclein (A53T). The TgM83(+/-) mice that were hemizygous for the mutant transgene did not develop spontaneous illness; in contrast, the TgM83(+/+) mice that were homozygous developed neurological dysfunction. Brain extracts from 14 MSA cases all transmitted neurodegeneration to TgM83(+/-) mice after incubation periods of ∼120 d, which was accompanied by deposition of α-synuclein within neuronal cell bodies and axons. All of the MSA extracts also induced aggregation of α-syn*A53T-YFP in cultured cells, whereas none of six Parkinson's disease (PD) extracts or a control sample did so. Our findings argue that MSA is caused by a unique strain of α-synuclein prions, which is different from the putative prions causing PD and from those causing spontaneous neurodegeneration in TgM83(+/+) mice. Remarkably, α-synuclein is the first new human prion to be identified, to our knowledge, since the discovery a half century ago that CJD was transmissible.
    Proceedings of the National Academy of Sciences 08/2015; DOI:10.1073/pnas.1514475112 · 9.67 Impact Factor
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    ABSTRACT: Increasingly, evidence argues that many neurodegenerative diseases, including progressive supranuclear palsy (PSP), are caused by prions, which are alternatively folded proteins undergoing self-propagation. In earlier studies, PSP prions were detected by infecting human embryonic kidney (HEK) cells expressing a tau fragment [TauRD(LM)] fused to yellow fluorescent protein (YFP). Here, we report on an improved bioassay using selective precipitation of tau prions from human PSP brain homogenates before infection of the HEK cells. Tau prions were measured by counting the number of cells with TauRD(LM)-YFP aggregates using confocal fluorescence microscopy. In parallel studies, we fused α-synuclein to YFP to bioassay α-synuclein prions in the brains of patients who died of multiple system atrophy (MSA). Previously, MSA prion detection required ∼120 d for transmission into transgenic mice, whereas our cultured cell assay needed only 4 d. Variation in MSA prion levels in four different brain regions from three patients provided evidence for three different MSA prion strains. Attempts to demonstrate α-synuclein prions in brain homogenates from Parkinson's disease patients were unsuccessful, identifying an important biological difference between the two synucleinopathies. Partial purification of tau and α-synuclein prions facilitated measuring the levels of these protein pathogens in human brains. Our studies should facilitate investigations of the pathogenesis of both tau and α-synuclein prion disorders as well as help decipher the basic biology of those prions that attack the CNS.
    Proceedings of the National Academy of Sciences 08/2015; 112(35). DOI:10.1073/pnas.1513426112 · 9.67 Impact Factor
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    ABSTRACT: Aberrant self-assembly, induced by structural misfolding of the prion proteins, leads to a number of neurodegenerative disorders. In particular, misfolding of the mostly α-helical cellular prion protein (PrP(C)) into a β-sheet-rich disease-causing isoform (PrP(Sc)) is the key molecular event in the formation of PrP(Sc) aggregates. The molecular mechanisms underlying the PrP(C)-to-PrP(Sc) conversion and subsequent aggregation remain to be elucidated. However, in persistently prion-infected cell-culture models, it was shown that treatment with monoclonal antibodies against defined regions of the prion protein (PrP) led to the clearing of PrP(Sc) in cultured cells. To gain more insight into this process, we characterized PrP-antibody complexes in solution using a fast protein liquid chromatography coupled with small-angle x-ray scattering (FPLC-SAXS) procedure. High-quality SAXS data were collected for full-length recombinant mouse PrP [denoted recPrP(23-230)] and N-terminally truncated recPrP(89-230), as well as their complexes with each of two Fab fragments (HuM-P and HuM-R1), which recognize N- and C-terminal epitopes of PrP, respectively. In-line measurements by fast protein liquid chromatography coupled with SAXS minimized data artifacts caused by a non-monodispersed sample, allowing structural analysis of PrP alone and in complex with Fab antibodies. The resulting structural models suggest two mechanisms for how these Fabs may prevent the conversion of PrP(C) into PrP(Sc). Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.
    Biophysical Journal 08/2015; 109(4):793-805. DOI:10.1016/j.bpj.2015.06.065 · 3.97 Impact Factor
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    ABSTRACT: Because no drug exists that halts or even slows any neurodegenerative disease, developing effective therapeutics for any prion disorder is urgent. We recently reported two compounds (IND24 and IND81) with the 2-aminothiazole (2-AMT) chemical scaffold that almost doubled the incubation times in scrapie prion-infected, wild-type (wt) FVB mice when given in a liquid diet (Berry et al., 2013). Remarkably, oral prophylactic treatment with IND24 beginning 14 d prior to intracerebral prion inoculation extended survival from ~120 days to over 450 days. In addition to IND24, we evaluated the pharmacokinetics and efficacy of five additional 2-AMTs; one was not followed further because its brain penetration was poor. Of the remaining four new 2-AMTs, IND114338 doubled and IND125 tripled the incubation times of RML-inoculated wt and Tg4053 mice overexpressing wt mouse PrP, respectively. Neuropathological examination of brains from untreated controls showed widespread deposition of PrP(Sc) prions accompanied by a profound astrocytic gliosis. In contrast, mice treated with 2-AMTs had lower levels of PrP(Sc) and associated astrocytic gliosis, with each compound resulting in a distinct pattern of deposition. Notably, IND125 prevented both PrP(Sc) accumulation and astrocytic gliosis in the cerebrum. Progressive CNS dysfunction in the IND125-treated mice was presumably due to the PrP(Sc) that accumulated in their brainstems. Disappointingly, none of the four new 2-AMTs prolonged the lives of mice expressing a chimeric human/mouse PrP transgene inoculated with Creutzfeldt-Jakob disease prions. The American Society for Pharmacology and Experimental Therapeutics.
    Journal of Pharmacology and Experimental Therapeutics 07/2015; 355(1). DOI:10.1124/jpet.115.224659 · 3.97 Impact Factor
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    ABSTRACT: Treatment with the 2-aminothiazole IND24 extended the survival of mice infected with mouse-adapted scrapie but also resulted in the emergence of a drug-resistant prion strain. Here, we determined whether IND24 extended the survival of transgenic mice infected with prions that caused scrapie in sheep or prions that caused chronic wasting disease (CWD; hereafter "CWD prions") in deer, using 2 isolates for each disease. IND24 doubled the incubation times for mice infected with CWD prions but had no effect on the survival of those infected with scrapie prions. Biochemical, neuropathologic, and cell culture analyses were used to characterize prion strain properties following treatment, and results indicated that the CWD prions were not altered by IND24, regardless of survival extension. These results suggest that IND24 may be a viable candidate for treating CWD in infected captive cervid populations and raise questions about why some prion strains develop drug resistance whereas others do not. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
    The Journal of Infectious Diseases 07/2015; 212(suppl 1). DOI:10.1093/infdis/jiu656 · 6.00 Impact Factor
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    ABSTRACT: Mutations in the gene encoding the prion protein (PrP) are responsible for approximately 10-15% of cases of prion disease in humans, including Creutzfeldt-Jakob disease (CJD). Here we report the discovery of a previously unreported C-terminal PrP mutation (A224V) in a CJD patient exhibiting a disease similar to the rare VV1 subtype of sporadic CJD and investigate the role of this mutation in prion replication and transmission. We generated transgenic (Tg) mice expressing human PrP with the V129 polymorphism and A224V mutation, denoted Tg(HuPrP,V129,A224V) mice, and inoculated them with different subtypes of sporadic (s) CJD prions. Transmission of sCJD VV2 or MV2 prions was accelerated in Tg(HuPrP,V129,A224V) mice compared to Tg(HuPrP,V129) mice, with incubation periods of ∼110 days and ∼210 days, respectively. In contrast, sCJD MM1 prions resulted in longer incubation periods in Tg(HuPrP,V129,A224V) mice compared to Tg(HuPrP,V129) mice (∼320 days v. ∼210 days). Prion strain fidelity was maintained in Tg(HuPrP,V129,A224V) mice inoculated with sCJD VV2 or MM1 prions, despite the altered replication kinetics. Our results suggest that A224V is a risk factor for prion disease and modulates the transmission behavior of CJD prions in a strain-specific manner, arguing that residues near the C-terminus of PrP are important for controlling the kinetics of prion replication. This article is protected by copyright. All rights reserved. © 2015 American Neurological Association.
    Annals of Neurology 06/2015; 78(4). DOI:10.1002/ana.24463 · 9.98 Impact Factor
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    ABSTRACT: Prions are proteins that adopt self-propagating aberrant folds. The self-propagating properties of prions are a direct consequence of their distinct structures, making the understanding of these structures and their biophysical interactions fundamental to understanding prions and their related diseases. The insolubility and inherent disorder of prions have made their structures difficult to study, particularly in the case of the infectious form of the mammalian prion protein PrP. Many investigators have therefore preferred to work with peptide fragments of PrP, suggesting that these peptides might serve as structural and functional models for biologically active prions. We have used x-ray fiber diffraction to compare a series of different-sized fragments of PrP, to determine the structural commonalities among the fragments and the biologically active, self-propagating prions. Although all of the peptides studied adopted amyloid conformations, only the larger fragments demonstrated a degree of structural complexity approaching that of PrP. Even these larger fragments did not adopt the prion structure itself with detailed fidelity, and in some cases their structures were radically different from that of pathogenic PrP(Sc). Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.
    Biophysical Journal 03/2015; 108(6):1548-54. DOI:10.1016/j.bpj.2015.01.008 · 3.97 Impact Factor
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    ABSTRACT: The phosphotungstate anion (PTA) is widely used to facilitate the precipitation of disease-causing prion protein (PrP(Sc)) from infected tissue for applications in structural studies and diagnostic approaches. However, the mechanism of this precipitation is not understood. In order to elucidate the nature of the PTA interaction with PrP(Sc) under physiological conditions, solutions of PTA were characterized by NMR spectroscopy at varying pH. At neutral pH, the parent [PW12O40](3-) ion decomposes to give a lacunary [PW11O39](7-) (PW11) complex and a single orthotungstate anion [WO4](2-) (WO4). To measure the efficacy of each component of PTA, increasing concentrations of PW11, WO4, and mixtures thereof were used to precipitate PrP(Sc) from brain homogenates of scrapie prion-infected mice. The amount of PrP(Sc) isolated, quantified by ELISA and immunoblotting, revealed that both PW11 and WO4 contribute to PrP(Sc) precipitation. Incubation with sarkosyl, PTA, or individual components of PTA resulted in separation of higher-density PrP aggregates from the neuronal lipid monosialotetrahexosylganglioside (GM1), as observed by sucrose gradient centrifugation. These experiments revealed that yield and purity of PrP(Sc) were greater with polyoxometalates (POMs), which substantially supported the separation of lipids from PrP(Sc) in the samples. Interaction of POMs and sarkosyl with brain homogenates promoted the formation of fibrillar PrP(Sc) aggregates prior to centrifugation, likely through the separation of lipids like GM1 from PrP(Sc). We propose that this separation of lipids from PrP is a major factor governing the facile precipitation of PrP(Sc) by PTA from tissue and might be optimized further for the detection of prions.
    ACS Chemical Biology 02/2015; 10(5). DOI:10.1021/cb5006239 · 5.33 Impact Factor
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    ABSTRACT: An increasing number of studies argues that self-propagating protein conformations (i.e., prions) feature in the pathogenesis of several common neurodegenerative diseases. Mounting evidence contends that aggregates of the amyloid-β (Aβ) peptide become self-propagating in Alzheimer's disease (AD) patients. An important characteristic of prions is their ability to replicate distinct strains, the biological information for which is enciphered within different conformations of protein aggregates. To investigate whether distinct strains of Aβ prions can be discerned in AD patients, we performed transmission studies in susceptible transgenic mice using brain homogenates from sporadic or heritable (Arctic and Swedish) AD cases. Mice inoculated with the Arctic AD sample exhibited a pathology that could be distinguished from mice inoculated with the Swedish or sporadic AD samples, which was judged by differential accumulation of Aβ isoforms and the morphology of cerebrovascular Aβ deposition. Unlike Swedish AD- or sporadic AD-inoculated animals, Arctic AD-inoculated mice, like Arctic AD patients, displayed a prominent Aβ38-containing cerebral amyloid angiopathy. The divergent transmission behavior of the Arctic AD sample compared with the Swedish and sporadic AD samples was maintained during second passage in mice, showing that Aβ strains are serially transmissible. We conclude that at least two distinct strains of Aβ prions can be discerned in the brains of AD patients and that strain fidelity was preserved on serial passage in mice. Our results provide a potential explanation for the clinical and pathological heterogeneity observed in AD patients.
    Proceedings of the National Academy of Sciences 06/2014; 111(28). DOI:10.1073/pnas.1408900111 · 9.67 Impact Factor
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    ABSTRACT: An increasing number of studies continue to show that the amyloid β (Aβ) peptide adopts an alternative conformation and acquires transmissibility; hence, it becomes a prion. Here, we report on the attributes of two strains of Aβ prions formed from synthetic Aβ peptides composed of either 40 or 42 residues. Modifying the conditions for Aβ polymerization increased both the protease resistance and prion infectivity compared with an earlier study. Approximately 150 d after intracerebral inoculation, both synthetic Aβ40 and Aβ42 prions produced a sustained rise in the bioluminescence imaging signal in the brains of bigenic Tg(APP23:Gfap-luc) mice, indicative of astrocytic gliosis. Pathological investigations showed that synthetic Aβ40 prions produced amyloid plaques containing both Aβ40 and Aβ42 in the brains of inoculated bigenic mice, whereas synthetic Aβ42 prions stimulated the formation of smaller, more numerous plaques composed predominantly of Aβ42. Synthetic Aβ40 preparations consisted of long straight fibrils; in contrast, the Aβ42 fibrils were much shorter. Addition of 3.47 mM (0.1%) SDS to the polymerization reaction produced Aβ42 fibrils that were indistinguishable from Aβ40 fibrils produced in the absence or presence of SDS. Moreover, the Aβ amyloid plaques in the brains of bigenic mice inoculated with Aβ42 prions prepared in the presence of SDS were similar to those found in mice that received Aβ40 prions. From these results, we conclude that the composition of Aβ plaques depends on the conformation of the inoculated Aβ polymers, and thus, these inocula represent distinct synthetic Aβ prion strains.
    Proceedings of the National Academy of Sciences 06/2014; 111(28). DOI:10.1073/pnas.1408968111 · 9.67 Impact Factor
  • Joel C Watts · Stanley B Prusiner
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    ABSTRACT: Prions are self-propagating protein conformations that cause a variety of neurodegenerative disorders in humans and animals. Mouse models have played key roles in deciphering the biology of prions and in assessing candidate therapeutics. The development of transgenic mice that form prions spontaneously in the brain has advanced our understanding of sporadic and genetic prion diseases. Furthermore, the realization that many proteins can become prions has necessitated the development of mouse models for assessing the potential transmissibility of common neurodegenerative diseases. As the universe of prion diseases continues to expand, mouse models will remain crucial for interrogating these devastating illnesses.
    Journal of Biological Chemistry 05/2014; 289(29). DOI:10.1074/jbc.R114.550707 · 4.57 Impact Factor
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    ABSTRACT: Bank voles are uniquely susceptible to a wide range of prion strains isolated from many different species. To determine if this enhanced susceptibility to interspecies prion transmission is encoded within the sequence of the bank vole prion protein (BVPrP), we inoculated Tg(M109) and Tg(I109) mice, which express BVPrP containing either methionine or isoleucine at polymorphic codon 109, with 16 prion isolates from 8 different species: humans, cattle, elk, sheep, guinea pigs, hamsters, mice, and meadow voles. Efficient disease transmission was observed in both Tg(M109) and Tg(I109) mice. For instance, inoculation of the most common human prion strain, sporadic Creutzfeldt-Jakob disease (sCJD) subtype MM1, into Tg(M109) mice gave incubation periods of ∼200 days that were shortened slightly on second passage. Chronic wasting disease prions exhibited an incubation time of ∼250 days, which shortened to ∼150 days upon second passage in Tg(M109) mice. Unexpectedly, bovine spongiform encephalopathy and variant CJD prions caused rapid neurological dysfunction in Tg(M109) mice upon second passage, with incubation periods of 64 and 40 days, respectively. Despite the rapid incubation periods, other strain-specified properties of many prion isolates-including the size of proteinase K-resistant PrPSc, the pattern of cerebral PrPSc deposition, and the conformational stability-were remarkably conserved upon serial passage in Tg(M109) mice. Our results demonstrate that expression of BVPrP is sufficient to engender enhanced susceptibility to a diverse range of prion isolates, suggesting that BVPrP may be a universal acceptor for prions.
    PLoS Pathogens 04/2014; 10(4):e1003990. DOI:10.1371/journal.ppat.1003990 · 7.56 Impact Factor
  • Proceedings of the National Academy of Sciences 03/2014; 111(10):3895-3895. DOI:10.1073/pnas.1401579111 · 9.67 Impact Factor
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    Proceedings of the National Academy of Sciences 03/2014; 111(9):3645-3645. DOI:10.1073/pnas.1401576111 · 9.67 Impact Factor
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    ABSTRACT: Purpose: Previous studies showed that lowering PrP(C) concomitantly reduced PrP(Sc) in the brains of mice inoculated with prions. We aimed to develop assays that measure PrP(C) on the surface of human T98G glioblastoma and IMR32 neuroblastoma cells. Using these assays, we sought to identify chemical hits, confirmed hits, and scaffolds that potently lowered PrP(C) levels in human brains cells, without lethality, and that could achieve drug concentrations in the brain after oral or intraperitoneal dosing in mice. Methods: We utilized HTS ELISA assays to identify small molecules that lower PrP(C) levels by ≥30% on the cell surface of human glioblastoma (T98G) and neuroblastoma (IMR32) cells. Results: From 44,578 diverse chemical compounds tested, 138 hits were identified by single point confirmation (SPC) representing 7 chemical scaffolds in T98G cells, and 114 SPC hits representing 6 scaffolds found in IMR32 cells. When the confirmed SPC hits were combined with structurally related analogs, >300 compounds (representing 6 distinct chemical scaffolds) were tested for dose-response (EC₅₀) in both cell lines, only studies in T98G cells identified compounds that reduced PrP(C) without killing the cells. EC₅₀ values from 32 hits ranged from 65 nM to 4.1 μM. Twenty-eight were evaluated in vivo in pharmacokinetic studies after a single 10 mg/kg oral or intraperitoneal dose in mice. Our results showed brain concentrations as high as 16.2 μM, but only after intraperitoneal dosing. Conclusions: Our studies identified leads for future studies to determine which compounds might lower PrP(C) levels in rodent brain, and provide the basis of a therapeutic for fatal disorders caused by PrP prions.
    Bioorganic & medicinal chemistry 03/2014; 22(6). DOI:10.1016/j.bmc.2014.01.001 · 2.79 Impact Factor
  • Stanley B Prusiner
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    ABSTRACT: Prions are proteins that acquire alternative conformations that become self-propagating. Transformation of proteins into prions is generally accompanied by an increase in β-sheet structure and a propensity to aggregate into oligomers. Some prions are beneficial and perform cellular functions, whereas others cause neurodegeneration. In mammals, more than a dozen proteins that become prions have been identified, and a similar number has been found in fungi. In both mammals and fungi, variations in the prion conformation encipher the biological properties of distinct prion strains. Increasing evidence argues that prions cause many neurodegenerative diseases (NDs), including Alzheimer's, Parkinson's, Creutzfeldt-Jakob, and Lou Gehrig's diseases, as well as the tauopathies. The majority of NDs are sporadic, and 10% to 20% are inherited. The late onset of heritable NDs, like their sporadic counterparts, may reflect the stochastic nature of prion formation; the pathogenesis of such illnesses seems to require prion accumulation to exceed some critical threshold before neurological dysfunction manifests.
    Annual Review of Genetics 11/2013; 47(1):601-23. DOI:10.1146/annurev-genet-110711-155524 · 15.72 Impact Factor
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    ABSTRACT: Prions are proteins that adopt alternative conformations, which become self-propagating. Increasing evidence argues that prions feature in the synucleinopathies that include Parkinson's disease, Lewy body dementia, and multiple system atrophy (MSA). Although TgM83(+/+) mice homozygous for a mutant A53T α-synuclein transgene begin developing CNS dysfunction spontaneously at ∼10 mo of age, uninoculated TgM83(+/-) mice (hemizygous for the transgene) remain healthy. To determine whether MSA brains contain α-synuclein prions, we inoculated the TgM83(+/-) mice with brain homogenates from two pathologically confirmed MSA cases. Inoculated TgM83(+/-) mice developed progressive signs of neurologic disease with an incubation period of ∼100 d, whereas the same mice inoculated with brain homogenates from spontaneously ill TgM83(+/+) mice developed neurologic dysfunction in ∼210 d. Brains of MSA-inoculated mice exhibited prominent astrocytic gliosis and microglial activation as well as widespread deposits of phosphorylated α-synuclein that were proteinase K sensitive, detergent insoluble, and formic acid extractable. Our results provide compelling evidence that α-synuclein aggregates formed in the brains of MSA patients are transmissible and, as such, are prions. The MSA prion represents a unique human pathogen that is lethal upon transmission to Tg mice and as such, is reminiscent of the prion causing kuru, which was transmitted to chimpanzees nearly 5 decades ago.
    Proceedings of the National Academy of Sciences 11/2013; 110(48). DOI:10.1073/pnas.1318268110 · 9.67 Impact Factor
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    ABSTRACT: There is not a single pharmaceutical that halts or even slows any neurodegenerative disease. Mounting evidence shows that prions cause many neurodegenerative diseases, and arguably, scrapie and Creutzfeldt-Jakob disease prions represent the best therapeutic targets. We report here that the previously identified 2-aminothiazoles IND24 and IND81 doubled the survival times of scrapie-infected, wild-type mice. However, mice infected with Rocky Mountain Laboratory (RML) prions, a scrapie-derived strain, and treated with IND24 eventually exhibited neurological dysfunction and died. We serially passaged their brain homogenates in mice and cultured cells. We found that the prion strain isolated from IND24-treated mice, designated RML[IND24], emerged during a single passage in treated mice. Although RML prions infect both the N2a and CAD5 cell lines, RML[IND24] prions could only infect CAD5 cells. When passaged in CAD5 cells, the prions remained resistant to high concentrations of IND24. However, one passage of RML[IND24] prions in untreated mice restored susceptibility to IND24 in CAD5 cells. Although IND24 treatment extended the lives of mice propagating different prion strains, including RML, another scrapie-derived prion strain ME7, and chronic wasting disease, it was ineffective in slowing propagation of Creutzfeldt-Jakob disease prions in transgenic mice. Our studies demonstrate that prion strains can acquire resistance upon exposure to IND24 that is lost upon passage in mice in the absence of IND24. These data suggest that monotherapy can select for resistance, thus intermittent therapy with mixtures of antiprion compounds may be required to slow or stop neurodegeneration.
    Proceedings of the National Academy of Sciences 10/2013; 110(44). DOI:10.1073/pnas.1317164110 · 9.67 Impact Factor
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    ABSTRACT: To determine whether oral quinacrine increases survival in sporadic Creutzfeldt-Jakob disease (sCJD). This NIH/National Institute on Aging-funded, double-blinded, placebo-controlled, stratified randomization treatment trial was conducted at the University of California, San Francisco from February 2005 through May 2009 (ClinicalTrials.gov, NCT00183092). Subjects were randomized (50:50) to quinacrine (300 mg daily) or placebo with inpatient evaluations at baseline, and planned for months 2, 6, and 12. Subjects returning for their month-2 visit were offered open-label quinacrine. The primary outcome was survival from randomization to month 2. Of 425 patients referred, 69 subjects enrolled, 54 subjects were randomized to active drug or placebo, and 51 subjects with sCJD were included in survival analyses. Survival for the randomized portion of the trial (first 2 months) showed no significant difference between the 2 groups (log-rank statistic, p = 0.43; Cox proportional relative hazard = 1.43, quinacrine compared with placebo, 95% confidence interval = 0.58, 3.53). The quinacrine-treated group, however, declined less on 2 of 3 functional scales, the modified Rankin and Clinical Dementia Rating, than the placebo group during the first 2 months. This interventional study provides Class I evidence that oral quinacrine at 300 mg per day does not improve 2-month survival of patients with sCJD, compared with placebo. Importantly, this study shows that double-blinded, placebo-controlled, randomized treatment trials are possible in prion disease. Furthermore, the quantitative data collected on the course of sCJD will be useful for future trials. This study provides Class I evidence that quinacrine does not improve survival for people with sCJD when given orally at a dose of 300 mg per day for 2 months.
    Neurology 10/2013; 81(23). DOI:10.1212/WNL.0b013e3182a9f3b4 · 8.29 Impact Factor
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    ABSTRACT: During prion diseases, a normally benign, host protein, denoted PrP(C), undergoes alternative folding into the aberrant isoform, PrP(Sc). We used ELISA to identify and confirm hits in order to develop leads that reduce PrP(Sc) in prion-infected dividing and stationary-phase mouse neuroblastoma (ScN2a-cl3) cells. We tested 52,830 diverse small molecules in dividing cells and 49,430 in stationary-phase cells. This led to 3100 HTS and 970 single point confirmed (SPC) hits in dividing cells, 331 HTS and 55 confirmed SPC hits in stationary-phase cells as well as 36 confirmed SPC hits active in both. Fourteen chemical leads were identified from confirmed SPC hits in dividing cells and three in stationary-phase cells. From more than 682 compounds tested in concentration-effect relationships in dividing cells to determine potency (EC50), 102 had EC50 values between 1 and 10μM and 50 had EC50 values of <1μM; none affected cell viability. We observed an excellent correlation between EC50 values determined by ELISA and Western immunoblotting for 28 representative compounds in dividing cells (R(2)=0.75; p <0.0001). Of the 55 confirmed SPC hits in stationary-phase cells, 23 were piperazine, indole, or urea leads. The EC50 values of one indole in stationary-phase and dividing ScN2a-cl3 cells were 7.5 and 1.6μM, respectively. Unexpectedly, the number of hits in stationary-phase cells was ∼10% of that in dividing cells. The explanation for this difference remains to be determined.
    Bioorganic & medicinal chemistry 09/2013; 21(24). DOI:10.1016/j.bmc.2013.09.022 · 2.79 Impact Factor

Publication Stats

59k Citations
4,947.53 Total Impact Points


  • 1976–2015
    • University of California, San Francisco
      • • Institute for Neurodegenerative Diseases
      • • Department of Neurology
      • • Department of Biochemistry and Biophysics
      • • Department of Pathology
      • • Division of Hospital Medicine
      San Francisco, California, United States
  • 2013
    • Institute for Neurodegenerative Disorders
      New Haven, Connecticut, United States
  • 2009
    • Mount Sinai School of Medicine
      • Department of Neurology
      Manhattan, NY, United States
  • 1991–2008
    • Heinrich-Heine-Universität Düsseldorf
      • • Institute of Physical Biology
      • • Institute of Physical Chemistry
      Düsseldorf, North Rhine-Westphalia, Germany
  • 2007
    • European Commission - Joint Research Centre
      • Institute for Reference Materials and Measurements
      Brussels, BRU, Belgium
  • 2004
    • University of Toronto
      • Tanz Centre for Research in Neurodegenerative Diseases
      Toronto, Ontario, Canada
  • 1997–2003
    • University of California, Santa Cruz
      • Department of Chemistry & Biochemistry
      Santa Cruz, CA, United States
    • CSU Mentor
      • Department of Neurology
      Long Beach, California, United States
  • 1999–2001
    • University of Oxford
      • Department of Biochemistry
      Oxford, ENG, United Kingdom
    • Cold Spring Harbor Laboratory
      Cold Spring Harbor, New York, United States
  • 2000
    • Molecular and Cellular Biology Program
      Seattle, Washington, United States
  • 1983–1999
    • University of California, Berkeley
      • • Department of Molecular and Cell Biology
      • • School of Public Health
      Berkeley, California, United States
  • 1998
    • Institute of Biochemistry and Biophysics
      Teheran, Tehrān, Iran
  • 1996
    • California State University
      • Department of Neurology
      Long Beach, California, United States
    • The Scripps Research Institute
      • Department of Cell and Molecular Biology
      La Jolla, California, United States
    • Hadassah Medical Center
      • Department of Neurology
      Jerusalem, Jerusalem District, Israel
  • 1995
    • University of San Francisco
      San Francisco, California, United States
  • 1994
    • Columbia University
      New York, New York, United States
  • 1989–1994
    • McLaughlin Research Institute
      Great Falls, Montana, United States
  • 1990
    • University of Washington Seattle
      • Department of Pathology
      Seattle, Washington, United States
  • 1988–1989
    • The Jackson Laboratory
      Bar Harbor, Maine, United States
    • University of California, San Diego
      • Department of Pathology
      San Diego, California, United States
  • 1987
    • San Diego Zoo
      San Diego, California, United States
    • Kyushu University
      • Department of Neuropathology
      Hukuoka, Fukuoka, Japan
  • 1984
    • Orlando Health
      Orlando, Florida, United States
    • California Institute of Technology
      • Division of Biology
      Pasadena, California, United States
  • 1980–1981
    • Howard Hughes Medical Institute
      Ashburn, Virginia, United States
    • National Institute of Allergy and Infectious Diseases
      Maryland, United States
  • 1978
    • Hamilton College
      Клинтон, New York, United States