1
|
Race B, Williams K, Baune C, Striebel JF, Long D, Thomas T, Lubke L, Chesebro B, Carroll JA. Microglia have limited influence on early prion pathogenesis, clearance, or replication. PLoS One 2022; 17:e0276850. [PMID: 36301895 PMCID: PMC9612458 DOI: 10.1371/journal.pone.0276850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/14/2022] [Indexed: 11/07/2022] Open
Abstract
Microglia (MG) are critical to host defense during prion infection, but the mechanism(s) of this neuroprotection are poorly understood. To better examine the influence of MG during prion infection, we reduced MG in the brains of C57BL/10 mice using PLX5622 and assessed prion clearance and replication using multiple approaches that included bioassay, immunohistochemistry, and Real-Time Quaking Inducted Conversion (RT-QuIC). We also utilized a strategy of intermittent PLX5622 treatments to reduce MG and allow MG repopulation to test whether new MG could alter prion disease progress. Lastly, we investigated the influence of MG using tga20 mice, a rapid prion model that accumulates fewer pathological features and less PrPres in the infected brain. In C57BL/10 mice we found that MG were excluded from the inoculation site early after infection, but Iba1 positive infiltrating monocytes/macrophage were present. Reducing MG in the brain prior to prion inoculation did not increase susceptibility to prion infection. Short intermittent treatments with PLX5622 in prion infected C57BL/10 mice after 80 dpi were unsuccessful at altering the MG population, gliosis, or survival. Additionally, MG depletion using PLX5622 in tga20 mice had only a minor impact on prion pathogenesis, indicating that the presence of MG might be less important in this fast model with less prion accumulation. In contrast to the benefits of MG against prion disease in late stages of disease, our current experiments suggest MG do not play a role in early prion pathogenesis, clearance, or replication.
Collapse
Affiliation(s)
- Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail: (BR); (JAC)
| | - Katie Williams
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Chase Baune
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James F. Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Dan Long
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Tina Thomas
- Rocky Mountain Veterinary Branch, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Lori Lubke
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - James A. Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail: (BR); (JAC)
| |
Collapse
|
2
|
Emami Kazemabad MJ, Asgari Toni S, Tizro N, Dadkhah PA, Amani H, Akhavan Rezayat S, Sheikh Z, Mohammadi M, Alijanzadeh D, Alimohammadi F, Shahrokhi M, Erabi G, Noroozi M, Karimi MA, Honari S, Deravi N. Pharmacotherapeutic potential of pomegranate in age-related neurological disorders. Front Aging Neurosci 2022; 14:955735. [PMID: 36118710 PMCID: PMC9476556 DOI: 10.3389/fnagi.2022.955735] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 07/13/2022] [Indexed: 11/24/2022] Open
Abstract
Age-related neurological disorders [AND] include neurodegenerative diseases [NDDs] such as Alzheimer's disease [AD] and Parkinson's disease [PD], which are the most prevalent types of dementia in the elderly. It also includes other illnesses such as migraine and epilepsy. ANDs are multifactorial, but aging is their major risk factor. The most frequent and vital pathological features of AND are oxidative stress, inflammation, and accumulation of misfolded proteins. As AND brain damage is a significant public health burden and its incidence is increasing, much has been done to overcome it. Pomegranate (Punica granatum L.) is one of the polyphenol-rich fruits that is widely mentioned in medical folklore. Pomegranate is commonly used to treat common disorders such as diarrhea, abdominal pain, wound healing, bleeding, dysentery, acidosis, microbial infections, infectious and noninfectious respiratory diseases, and neurological disorders. In the current review article, we aimed to summarize the data on the pharmacotherapeutic potentials of pomegranate in ANDs.
Collapse
Affiliation(s)
| | - Sara Asgari Toni
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Neda Tizro
- School of Medicine, Guilan University of Medical Sciences, Rasht, Iran
| | - Parisa Alsadat Dadkhah
- Student Research Committee, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Hanieh Amani
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Shima Akhavan Rezayat
- Student Research Committee, Faculty of Medicine, Islamic Azad University of Mashhad, Mashhad, Iran
| | - Zahra Sheikh
- Student Research Committee, School of Medicine, Babol University of Medical Sciences, Babol, Iran
| | - Mohammad Mohammadi
- Student Research Committee, School of Medicine, Shahid Sadoughi University of Medical Sciences, Yazd, Iran
| | - Dorsa Alijanzadeh
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Farnoosh Alimohammadi
- Student Research Committee, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Gisou Erabi
- Student Research Committee, Urmia University of Medical Sciences, Urmia, Iran
| | - Masoud Noroozi
- Department of Biomedical Engineering, Faculty of Engineering, University of Isfahan, Isfahan, Iran
| | - Mohammad Amin Karimi
- School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sara Honari
- Student Research Committee, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Niloofar Deravi
- Student Research Committee, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| |
Collapse
|
3
|
Deletion of Kif5c Does Not Alter Prion Disease Tempo or Spread in Mouse Brain. Viruses 2021; 13:v13071391. [PMID: 34372599 PMCID: PMC8310152 DOI: 10.3390/v13071391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 07/06/2021] [Accepted: 07/15/2021] [Indexed: 11/16/2022] Open
Abstract
In prion diseases, the spread of infectious prions (PrPSc) is thought to occur within nerves and across synapses of the central nervous system (CNS). However, the mechanisms by which PrPSc moves within axons and across nerve synapses remain undetermined. Molecular motors, including kinesins and dyneins, transport many types of intracellular cargo. Kinesin-1C (KIF5C) has been shown to transport vesicles carrying the normal prion protein (PrPC) within axons, but whether KIF5C is involved in PrPSc axonal transport is unknown. The current study tested whether stereotactic inoculation in the striatum of KIF5C knock-out mice (Kif5c−/−) with 0.5 µL volumes of mouse-adapted scrapie strains 22 L or ME7 would result in an altered rate of prion spreading and/or disease timing. Groups of mice injected with each strain were euthanized at either pre-clinical time points or following the development of prion disease. Immunohistochemistry for PrP was performed on brain sections and PrPSc distribution and tempo of spread were compared between mouse strains. In these experiments, no differences in PrPSc spread, distribution or survival times were observed between C57BL/6 and Kif5c−/− mice.
Collapse
|
4
|
Martin D, Reine F, Herzog L, Igel-Egalon A, Aron N, Michel C, Moudjou M, Fichet G, Quadrio I, Perret-Liaudet A, Andréoletti O, Rezaei H, Béringue V. Prion potentiation after life-long dormancy in mice devoid of PrP. Brain Commun 2021; 3:fcab092. [PMID: 33997785 PMCID: PMC8111064 DOI: 10.1093/braincomms/fcab092] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/26/2021] [Accepted: 04/01/2021] [Indexed: 12/26/2022] Open
Abstract
Prions are neurotropic pathogens composed of misfolded assemblies of the host-encoded prion protein PrPC which replicate by recruitment and conversion of further PrPC by an autocatalytic seeding polymerization process. While it has long been shown that mouse-adapted prions cannot replicate and are rapidly cleared in transgenic PrP0/0 mice invalidated for PrPC, these experiments have not been done with other prions, including from natural resources, and more sensitive methods to detect prion biological activity. Using transgenic mice expressing human PrP to bioassay prion infectivity and RT-QuIC cell-free assay to measure prion seeding activity, we report that prions responsible for the most prevalent form of sporadic Creutzfeldt-Jakob disease in human (MM1-sCJD) can persist indefinitely in the brain of intra-cerebrally inoculated PrP0/0 mice. While low levels of seeding activity were measured by RT-QuIC in the brain of the challenged PrP0/0 mice, the bio-indicator humanized mice succumbed at a high attack rate, suggesting relatively high levels of persistent infectivity. Remarkably, these humanized mice succumbed with delayed kinetics as compared to MM1-sCJD prions directly inoculated at low doses, including the limiting one. Yet, the disease that did occur in the humanized mice on primary and subsequent back-passage from PrP0/0 mice shared the neuropathological and molecular characteristics of MM1-sCJD prions, suggesting no apparent strain evolution during lifelong dormancy in PrP0/0 brain. Thus, MM1-sCJD prions can persist for the entire life in PrP0/0 brain with potential disease potentiation on retrotransmission to susceptible hosts. These findings highlight the capacity of prions to persist and rejuvenate in non-replicative environments, interrogate on the type of prion assemblies at work and alert on the risk of indefinite prion persistence with PrP-lowering therapeutic strategies.
Collapse
Affiliation(s)
- Davy Martin
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | - Fabienne Reine
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | - Laetitia Herzog
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | | | - Naima Aron
- INRAE, École Nationale Vétérinaire de Toulouse, IHAP, 31 000 Toulouse, France
| | - Christel Michel
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | - Mohammed Moudjou
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | - Guillaume Fichet
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | - Isabelle Quadrio
- Neurobiology Laboratory, Biochemistry and Molecular Biology Department, Hôpitaux de Lyon, 69 000 Lyon, France.,University of Lyon 1, CNRS UMR5292, INSERM U1028, BioRan, 69 000 Lyon, France
| | - Armand Perret-Liaudet
- Neurobiology Laboratory, Biochemistry and Molecular Biology Department, Hôpitaux de Lyon, 69 000 Lyon, France.,University of Lyon 1, CNRS UMR5292, INSERM U1028, BioRan, 69 000 Lyon, France
| | - Olivier Andréoletti
- INRAE, École Nationale Vétérinaire de Toulouse, IHAP, 31 000 Toulouse, France
| | - Human Rezaei
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| | - Vincent Béringue
- Université Paris-Saclay, INRAE, UVSQ, VIM, 78 350 Jouy-en-Josas, France
| |
Collapse
|
5
|
Defining the Protein Seeds of Neurodegeneration using Real-Time Quaking-Induced Conversion Assays. Biomolecules 2020; 10:biom10091233. [PMID: 32854212 PMCID: PMC7564261 DOI: 10.3390/biom10091233] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 08/17/2020] [Accepted: 08/20/2020] [Indexed: 02/07/2023] Open
Abstract
Neurodegenerative diseases are characterized by the accumulation of disease-related misfolded proteins. It is now widely understood that the characteristic self-amplifying (i.e., seeding) capacity once only attributed to the prions of transmissible spongiform encephalopathy diseases is a feature of other misfolded proteins of neurodegenerative diseases, including tau, Aβ, and αSynuclein (αSyn). Ultrasensitive diagnostic assays, known as real-time quaking-induced conversion (RT-QuIC) assays, exploit these seeding capabilities in order to exponentially amplify protein seeds from various biospecimens. To date, RT-QuIC assays have been developed for the detection of protein seeds related to known prion diseases of mammals, the αSyn aggregates of Parkinson’s disease, dementia with Lewy bodies, and multiple system atrophy, and the tau aggregates of Alzheimer’s disease, chronic traumatic encephalopathy, and other tauopathies including progressive supranuclear palsy. Application of these assays to premortem human biospecimens shows promise for diagnosis of neurodegenerative disease and is an area of active investigation. RT-QuIC assays are also powerful experimental tools that can be used to dissect seeding networks within and between tissues and to evaluate how protein seed distribution and quantity correlate to disease-related outcomes in a host. As well, RT-QuIC application may help characterize molecular pathways influencing protein seed accumulation, transmission, and clearance. In this review we discuss the application of RT-QuIC assays as diagnostic, experimental, and structural tools for detection and discrimination of PrP prions, tau, and αSyn protein seeds.
Collapse
|
6
|
Altered distribution, aggregation, and protease resistance of cellular prion protein following intracranial inoculation. PLoS One 2019; 14:e0219457. [PMID: 31291644 PMCID: PMC6620108 DOI: 10.1371/journal.pone.0219457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 06/24/2019] [Indexed: 11/19/2022] Open
Abstract
Prion protein (PrPC) is a protease-sensitive and soluble cell surface glycoprotein expressed in almost all mammalian cell types. PrPSc, a protease-resistant and insoluble form of PrPC, is the causative agent of prion diseases, fatal and transmissible neurogenerative diseases of mammals. Prion infection is initiated via either ingestion or inoculation of PrPSc or when host PrPC stochastically refolds into PrPSc. In either instance, the early events that occur during prion infection remain poorly understood. We have used transgenic mice expressing mouse PrPC tagged with a unique antibody epitope to monitor the response of host PrPC to prion inoculation. Following intracranial inoculation of either prion-infected or uninfected brain homogenate, we show that host PrPC can accumulate both intra-axonally and within the myelin membrane of axons suggesting that it may play a role in axonal loss following brain injury. Moreover, in response to the inoculation host PrPC exhibits an increased insolubility and protease resistance similar to that of PrPSc, even in the absence of infectious prions. Thus, our results raise the possibility that damage to the brain may be one trigger by which PrPC stochastically refolds into pathogenic PrPSc leading to productive prion infection.
Collapse
|
7
|
Heterogeneity and Architecture of Pathological Prion Protein Assemblies: Time to Revisit the Molecular Basis of the Prion Replication Process? Viruses 2019; 11:v11050429. [PMID: 31083283 PMCID: PMC6563208 DOI: 10.3390/v11050429] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Revised: 05/07/2019] [Accepted: 05/08/2019] [Indexed: 01/24/2023] Open
Abstract
Prions are proteinaceous infectious agents responsible for a range of neurodegenerative diseases in animals and humans. Prion particles are assemblies formed from a misfolded, β-sheet rich, aggregation-prone isoform (PrPSc) of the host-encoded cellular prion protein (PrPC). Prions replicate by recruiting and converting PrPC into PrPSc, by an autocatalytic process. PrPSc is a pleiomorphic protein as different conformations can dictate different disease phenotypes in the same host species. This is the basis of the strain phenomenon in prion diseases. Recent experimental evidence suggests further structural heterogeneity in PrPSc assemblies within specific prion populations and strains. Still, this diversity is rather seen as a size continuum of assemblies with the same core structure, while analysis of the available experimental data points to the existence of structurally distinct arrangements. The atomic structure of PrPSc has not been elucidated so far, making the prion replication process difficult to understand. All currently available models suggest that PrPSc assemblies exhibit a PrPSc subunit as core constituent, which was recently identified. This review summarizes our current knowledge on prion assembly heterogeneity down to the subunit level and will discuss its importance with regard to the current molecular principles of the prion replication process.
Collapse
|
8
|
T. Islam AM, Adlard PA, Finkelstein DI, Lewis V, Biggi S, Biasini E, Collins SJ. Acute Neurotoxicity Models of Prion Disease. ACS Chem Neurosci 2018; 9:431-445. [PMID: 29393619 DOI: 10.1021/acschemneuro.7b00517] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Prion diseases are phenotypically diverse, transmissible, neurodegenerative disorders affecting both animals and humans. Misfolding of the normal prion protein (PrPC) into disease-associated conformers (PrPSc) is considered the critical etiological event underpinning prion diseases, with such misfolded isoforms linked to both disease transmission and neurotoxicity. Although important advances in our understanding of prion biology and pathogenesis have occurred over the last 3-4 decades, many fundamental questions remain to be resolved, including consensus regarding the principal pathways subserving neuronal dysfunction, as well as detailed biophysical characterization of PrPSc species transmitting disease and/or directly associated with neurotoxicity. In vivo and in vitro models have been, and remain, critical to furthering our understanding across many aspects of prion disease patho-biology. Prion animal models are arguably the most authentic in vivo models of neurodegeneration that exist and have provided valuable and multifarious insights into pathogenesis; however, they are expensive and time-consuming, and it can be problematic to clearly discern evidence of direct PrPSc neurotoxicity in the overall context of pathogenesis. In vitro models, in contrast, generally offer greater tractability and appear more suited to assessments of direct acute neurotoxicity but have until recently been relatively simplistic, and overall there remains a relative paucity of validated, biologically relevant models with heightened reliability as far as translational insights, contributing to difficulties in redressing our knowledge gaps in prion disease pathogenesis. In this review, we provide an overview of the spectrum and methodological diversity of in vivo and in vitro models of prion acute toxicity, as well as the pathogenic insights gained from these studies.
Collapse
Affiliation(s)
| | | | | | | | - S. Biggi
- CIBIO, University of Trento, 38123 Povo, Trento, Italy
| | - E. Biasini
- CIBIO, University of Trento, 38123 Povo, Trento, Italy
| | | |
Collapse
|
9
|
Race B, Williams K, Hughson AG, Jansen C, Parchi P, Rozemuller AJM, Chesebro B. Familial human prion diseases associated with prion protein mutations Y226X and G131V are transmissible to transgenic mice expressing human prion protein. Acta Neuropathol Commun 2018; 6:13. [PMID: 29458424 PMCID: PMC5819089 DOI: 10.1186/s40478-018-0516-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 02/11/2018] [Indexed: 11/21/2022] Open
Abstract
Human familial prion diseases are associated with mutations at 34 different prion protein (PrP) amino acid residues. However, it is unclear whether infectious prions are found in all cases. Mutant PrP itself may be neurotoxic, or alternatively, PrP mutation might predispose to spontaneous formation of infectious PrP isoforms. Previous reports demonstrated transmission to animal models by human brain tissue expressing 7 different PrP mutations, but 3 other mutations were not transmissible. In the present work, we tested transmission using brain homogenates from patients expressing 3 untested PrP mutants: G131V, Y226X, and Q227X. Human brain homogenates were injected intracerebrally into tg66 transgenic mice overexpressing human PrP. Mice were followed for nearly 800 days. From 593 to 762 dpi, 4 of 8 mice injected with Y226X brain had PrPSc detectable in brain by immunostaining, immunoblot, and PrP amyloid seeding activity assayed by RT-QuIC. From 531 to 784 dpi, 11 of 11 G131V-injected mice had PrPSc deposition in brain, but none were positive by immunoblot or RT-QuIC assay. In contrast, from 529 to 798 dpi, no tg66 mice injected with Q227X brain had PrPSc or PrP amyloid seeding activity detectable by these methods. Y226X is the only one of 4 known PrP truncations associated with familial disease which has been shown to be transmissible. This transmission of prion infectivity from a patient expressing truncated human PrP may have implications for the spread and possible transmission of other aggregated truncated proteins in prion-like diseases such as Alzheimer’s disease, Parkinson’s disease and tauopathies.
Collapse
|
10
|
PrP P102L and Nearby Lysine Mutations Promote Spontaneous In Vitro Formation of Transmissible Prions. J Virol 2017; 91:JVI.01276-17. [PMID: 28835493 DOI: 10.1128/jvi.01276-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Accepted: 08/14/2017] [Indexed: 12/16/2022] Open
Abstract
Accumulation of fibrillar protein aggregates is a hallmark of many diseases. While numerous proteins form fibrils by prion-like seeded polymerization in vitro, only some are transmissible and pathogenic in vivo To probe the structural features that confer transmissibility to prion protein (PrP) fibrils, we have analyzed synthetic PrP amyloids with or without the human prion disease-associated P102L mutation. The formation of infectious prions from PrP molecules in vitro has required cofactors and/or unphysiological denaturing conditions. Here, we demonstrate that, under physiologically compatible conditions without cofactors, the P102L mutation in recombinant hamster PrP promoted prion formation when seeded by minute amounts of scrapie prions in vitro Surprisingly, combination of the P102L mutation with charge-neutralizing substitutions of four nearby lysines promoted spontaneous prion formation. When inoculated into hamsters, both of these types of synthetic prions initiated substantial accumulation of prion seeding activity and protease-resistant PrP without transmissible spongiform encephalopathy (TSE) clinical signs or notable glial activation. Our evidence suggests that PrP's centrally located proline and lysine residues act as conformational switches in the in vitro formation of transmissible PrP amyloids.IMPORTANCE Many diseases involve the damaging accumulation of specific misfolded proteins in thread-like aggregates. These threads (fibrils) are capable of growing on the ends by seeding the refolding and incorporation of the normal form of the given protein. In many cases such aggregates can be infectious and propagate like prions when transmitted from one individual host to another. Some transmitted aggregates can cause fatal disease, as with human iatrogenic prion diseases, while other aggregates appear to be relatively innocuous. The factors that distinguish infectious and pathogenic protein aggregates from more innocuous ones are poorly understood. Here we have compared the combined effects of prion seeding and mutations of prion protein (PrP) on the structure and transmission properties of synthetic PrP aggregates. Our results highlight the influence of specific sequence features in the normally unstructured region of PrP that influence the infectious and neuropathogenic properties of PrP-derived aggregates.
Collapse
|
11
|
Kondru N, Manne S, Greenlee J, West Greenlee H, Anantharam V, Halbur P, Kanthasamy A, Kanthasamy A. Integrated Organotypic Slice Cultures and RT-QuIC (OSCAR) Assay: Implications for Translational Discovery in Protein Misfolding Diseases. Sci Rep 2017; 7:43155. [PMID: 28233859 PMCID: PMC5324099 DOI: 10.1038/srep43155] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 01/19/2017] [Indexed: 01/13/2023] Open
Abstract
Protein misfolding is a key pathological event in neurodegenerative diseases like prion diseases, synucleinopathies, and tauopathies that are collectively termed protein misfolding disorders. Prions are a prototypic model to study protein aggregation biology and therapeutic development. Attempts to develop anti-prion therapeutics have been impeded by the lack of screening models that faithfully replicate prion diseases and the lack of rapid, sensitive biological screening systems. Therefore, a sensitive model encompassing prion replication and neurotoxicity would be indispensable to the pursuit of intervention strategies. We present an ultra-sensitive screening system coupled to an ex vivo prion organotypic slice culture model to rapidly advance rationale-based high-throughput therapeutic strategies. This hybrid Organotypic Slice Culture Assay coupled with RT-QuIC (OSCAR) permits sensitive, specific and quantitative detection of prions from an infectious slice culture model on a reduced time scale. We demonstrate that the anti-prion activity of test compounds can be readily resolved based on the power and kinetics of seeding activity in the OSCAR screening platform and that the prions generated in slice cultures are biologically active. Collectively, our results imply that OSCAR is a robust model of prion diseases that offers a promising platform for understanding prion proteinopathies and advancing anti-prion therapeutics.
Collapse
Affiliation(s)
- Naveen Kondru
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Sireesha Manne
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Justin Greenlee
- Virus and Prion Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA 50011, USA
| | - Heather West Greenlee
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Vellareddy Anantharam
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Patrick Halbur
- Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Arthi Kanthasamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| | - Anumantha Kanthasamy
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA
| |
Collapse
|
12
|
Carroll JA, Striebel JF, Rangel A, Woods T, Phillips K, Peterson KE, Race B, Chesebro B. Prion Strain Differences in Accumulation of PrPSc on Neurons and Glia Are Associated with Similar Expression Profiles of Neuroinflammatory Genes: Comparison of Three Prion Strains. PLoS Pathog 2016; 12:e1005551. [PMID: 27046083 PMCID: PMC4821575 DOI: 10.1371/journal.ppat.1005551] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 03/14/2016] [Indexed: 12/31/2022] Open
Abstract
Misfolding and aggregation of host proteins are important features of the pathogenesis of neurodegenerative diseases including Alzheimer’s disease, Parkinson’s disease, frontotemporal dementia and prion diseases. In all these diseases, the misfolded protein increases in amount by a mechanism involving seeded polymerization. In prion diseases, host prion protein is misfolded to form a pathogenic protease-resistant form, PrPSc, which accumulates in neurons, astroglia and microglia in the CNS. Here using dual-staining immunohistochemistry, we compared the cell specificity of PrPSc accumulation at early preclinical times post-infection using three mouse scrapie strains that differ in brain regional pathology. PrPSc from each strain had a different pattern of cell specificity. Strain 22L was mainly associated with astroglia, whereas strain ME7 was mainly associated with neurons and neuropil. In thalamus and cortex, strain RML was similar to 22L, but in substantia nigra, RML was similar to ME7. Expression of 90 genes involved in neuroinflammation was studied quantitatively using mRNA from thalamus at preclinical times. Surprisingly, despite the cellular differences in PrPSc accumulation, the pattern of upregulated genes was similar for all three strains, and the small differences observed correlated with variations in the early disease tempo. Gene upregulation correlated with activation of both astroglia and microglia detected in early disease prior to vacuolar pathology or clinical signs. Interestingly, the profile of upregulated genes in scrapie differed markedly from that seen in two acute viral CNS diseases (LaCrosse virus and BE polytropic Friend retrovirus) that had reactive gliosis at levels similar to our prion-infected mice. Accumulation of aggregates of misfolded protein in brain is a common feature of the damage seen in several neurodegenerative diseases including prion disease, Alzheimer’s disease and Parkinson’s disease. In the present work three strains of prion disease differed in accumulation of the disease-associated prion protein (PrPSc) on neurons and astroglial cells. These patterns were first detectable in the thalamus at 40–60 days after inoculation. This coincided with initial detection of gliosis and PrPSc deposition, but was far in advance of clinical signs or spongiform pathology. In spite of the different patterns of cellular PrPSc deposition, these three strains had similar patterns of expression of a large number of genes known to be active during neuroinflammatory responses and gliosis. However, the gene upregulation in scrapie differed markedly from that seen in two neurovirulent viral diseases, which also had abundant glial responses similar to those observed with prion infection.
Collapse
Affiliation(s)
- James A. Carroll
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - James F. Striebel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Alejandra Rangel
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Tyson Woods
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Katie Phillips
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Karin E. Peterson
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Brent Race
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
| | - Bruce Chesebro
- Laboratory of Persistent Viral Diseases, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Disease, National Institutes of Health, Hamilton, Montana, United States of America
- * E-mail:
| |
Collapse
|
13
|
Detection of Atypical H-Type Bovine Spongiform Encephalopathy and Discrimination of Bovine Prion Strains by Real-Time Quaking-Induced Conversion. J Clin Microbiol 2016; 54:676-86. [PMID: 26739160 DOI: 10.1128/jcm.02731-15] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 12/25/2015] [Indexed: 12/30/2022] Open
Abstract
Prion diseases of cattle include the classical bovine spongiform encephalopathy (C-BSE) and the atypical H-type BSE (H-BSE) and L-type BSE (L-BSE) strains. Although the C- and L-BSE strains can be detected and discriminated by ultrasensitive real-time quaking-induced conversion (RT-QuIC) assays, no such test has yet been described for the detection of H-BSE or the discrimination of each of the major bovine prion strains. Here, we demonstrate an RT-QuIC assay for H-BSE that can detect as little as 10(-9) dilutions of brain tissue and neat cerebrospinal fluid samples from clinically affected cattle. Moreover, comparisons of the reactivities with different recombinant prion protein substrates and/or immunoblot band profiles of proteinase K-treated RT-QuIC reaction products indicated that H-, L-, and C-BSE have distinctive prion seeding activities and can be discriminated by RT-QuIC on this basis.
Collapse
|