1
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Jaeger-Ruckstuhl CA, Lo Y, Fulton E, Waltner OG, Shabaneh TB, Simon S, Muthuraman PV, Correnti CE, Newsom OJ, Engstrom IA, Kanaan SB, Bhise SS, Peralta JMC, Ruff R, Price JP, Stull SM, Stevens AR, Bugos G, Kluesner MG, Voillet V, Muhunthan V, Morrish F, Olson JM, Gottardo R, Sarthy JF, Henikoff S, Sullivan LB, Furlan SN, Riddell SR. Signaling via a CD27-TRAF2-SHP-1 axis during naive T cell activation promotes memory-associated gene regulatory networks. Immunity 2024; 57:287-302.e12. [PMID: 38354704 DOI: 10.1016/j.immuni.2024.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 09/26/2023] [Accepted: 01/11/2024] [Indexed: 02/16/2024]
Abstract
The interaction of the tumor necrosis factor receptor (TNFR) family member CD27 on naive CD8+ T (Tn) cells with homotrimeric CD70 on antigen-presenting cells (APCs) is necessary for T cell memory fate determination. Here, we examined CD27 signaling during Tn cell activation and differentiation. In conjunction with T cell receptor (TCR) stimulation, ligation of CD27 by a synthetic trimeric CD70 ligand triggered CD27 internalization and degradation, suggesting active regulation of this signaling axis. Internalized CD27 recruited the signaling adaptor TRAF2 and the phosphatase SHP-1, thereby modulating TCR and CD28 signals. CD27-mediated modulation of TCR signals promoted transcription factor circuits that induced memory rather than effector associated gene programs, which are induced by CD28 costimulation. CD27-costimulated chimeric antigen receptor (CAR)-engineered T cells exhibited improved tumor control compared with CD28-costimulated CAR-T cells. Thus, CD27 signaling during Tn cell activation promotes memory properties with relevance to T cell immunotherapy.
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Affiliation(s)
- Carla A Jaeger-Ruckstuhl
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA.
| | - Yun Lo
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Elena Fulton
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Olivia G Waltner
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Tamer B Shabaneh
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Sylvain Simon
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Pranav V Muthuraman
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Colin E Correnti
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Oliver J Newsom
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Ian A Engstrom
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Sami B Kanaan
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Shruti S Bhise
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Jobelle M C Peralta
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Raymond Ruff
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Jason P Price
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Sylvia M Stull
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Andrew R Stevens
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Grace Bugos
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Mitchell G Kluesner
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Valentin Voillet
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Vishaka Muhunthan
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Fionnuala Morrish
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - James M Olson
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Raphaël Gottardo
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Department of Statistics, University of Washington, Seattle, WA 98195, USA; Swiss Institute of Bioinformatics, University of Lausanne and Lausanne University Hospital, Lausanne 1011, Switzerland
| | - Jay F Sarthy
- Seattle Children's Hospital, Seattle, WA 98105, USA; Basic Science Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Steven Henikoff
- Basic Science Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Seattle, WA 98195, USA
| | - Lucas B Sullivan
- Human Biology Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA
| | - Scott N Furlan
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Seattle Children's Hospital, Seattle, WA 98105, USA
| | - Stanley R Riddell
- Translational Sciences and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, WA 98109, USA; Department of Medicine, University of Washington, Seattle, WA 98195, USA.
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2
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Shabaneh TB, Stevens AR, Stull SM, Shimp KR, Seaton BW, Gad EA, Jaeger-Ruckstuhl CA, Simon S, Koehne AL, Price JP, Olson JM, Hoffstrom BG, Jellyman D, Riddell SR. Systemically administered low-affinity HER2 CAR T cells mediate antitumor efficacy without toxicity. J Immunother Cancer 2024; 12:e008566. [PMID: 38325903 DOI: 10.1136/jitc-2023-008566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/03/2024] [Indexed: 02/09/2024] Open
Abstract
BACKGROUND The paucity of tumor-specific targets for chimeric antigen receptor (CAR) T-cell therapy of solid tumors necessitates careful preclinical evaluation of the therapeutic window for candidate antigens. Human epidermal growth factor receptor 2 (HER2) is an attractive candidate for CAR T-cell therapy in humans but has the potential for eliciting on-target off-tumor toxicity. We developed an immunocompetent tumor model of CAR T-cell therapy targeting murine HER2 (mHER2) and examined the effect of CAR affinity, T-cell dose, and lymphodepletion on safety and efficacy. METHODS Antibodies specific for mHER2 were generated, screened for affinity and specificity, tested for immunohistochemical staining of HER2 on normal tissues, and used for HER2-targeted CAR design. CAR candidates were evaluated for T-cell surface expression and the ability to induce T-cell proliferation, cytokine production, and cytotoxicity when transduced T cells were co-cultured with mHER2+ tumor cells in vitro. Safety and efficacy of various HER2 CARs was evaluated in two tumor models and normal non-tumor-bearing mice. RESULTS Mice express HER2 in the same epithelial tissues as humans, rendering these tissues vulnerable to recognition by systemically administered HER2 CAR T cells. CAR T cells designed with single-chain variable fragment (scFvs) that have high-affinity for HER2 infiltrated and caused toxicity to normal HER2-positive tissues but exhibited poor infiltration into tumors and antitumor activity. In contrast, CAR T cells designed with an scFv with low-affinity for HER2 infiltrated HER2-positive tumors and controlled tumor growth without toxicity. Toxicity mediated by high-affinity CAR T cells was independent of tumor burden and correlated with proliferation of CAR T cells post infusion. CONCLUSIONS Our findings illustrate the disadvantage of high-affinity CARs for targets such as HER2 that are expressed on normal tissues. The use of low-affinity HER2 CARs can safely regress tumors identifying a potential path for therapy of solid tumors that exhibit high levels of HER2.
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Affiliation(s)
- Tamer Basel Shabaneh
- Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Andrew R Stevens
- Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Sylvia M Stull
- Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Kristen R Shimp
- Translational Science and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Brandon W Seaton
- Translational Science and Therapeutics Division, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Ekram A Gad
- Comparative Medicine, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Carla A Jaeger-Ruckstuhl
- Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Sylvain Simon
- Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Amanda L Koehne
- Experimental Histopathology, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Jason P Price
- Molecular Design and Therapeutics, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - James M Olson
- Molecular Design and Therapeutics, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | | | - David Jellyman
- Antibody Technology, Fred Hutchinson Cancer Center, Seattle, Washington, USA
| | - Stanley R Riddell
- Immunotherapy Integrated Research Center, Fred Hutchinson Cancer Center, Seattle, Washington, USA
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3
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Nealy ES, Reed SJ, Adelmund SM, Badeau BA, Shadish JA, Girard EJ, Pakiam FJ, Mhyre AJ, Price JP, Sarkar S, Kalia V, DeForest CA, Olson JM. Versatile Tissue-Injectable Hydrogels with Extended Hydrolytic Release of Bioactive Protein Therapeutics. bioRxiv 2023:2023.09.01.554391. [PMID: 37693598 PMCID: PMC10491173 DOI: 10.1101/2023.09.01.554391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Hydrogels generally have broad utilization in healthcare due to their tunable structures, high water content, and inherent biocompatibility. FDA-approved applications of hydrogels include spinal cord regeneration, skin fillers, and local therapeutic delivery. Drawbacks exist in the clinical hydrogel space, largely pertaining to inconsistent therapeutic exposure, short-lived release windows, and difficulties inserting the polymer into tissue. In this study, we engineered injectable, biocompatible hydrogels that function as a local protein therapeutic depot with a high degree of user-customizability. We showcase a PEG-based hydrogel functionalized with bioorthogonal strain-promoted azide-alkyne cycloaddition (SPAAC) handles for its polymerization and functionalization with a variety of payloads. Small-molecule and protein cargos, including chemokines and antibodies, were site-specifically modified with hydrolysable "azidoesters" of varying hydrophobicity via direct chemical conjugation or sortase-mediated transpeptidation. These hydrolysable esters afforded extended release of payloads linked to our hydrogels beyond diffusion; with timescales spanning days to months dependent on ester hydrophobicity. Injected hydrogels polymerize in situ and remain in tissue over extended periods of time. Hydrogel-delivered protein payloads elicit biological activity after being modified with SPAAC-compatible linkers, as demonstrated by the successful recruitment of murine T-cells to a mouse melanoma model by hydrolytically released murine CXCL10. These results highlight a highly versatile, customizable hydrogel-based delivery system for local delivery of protein therapeutics with payload release profiles appropriate for a variety of clinical needs.
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Affiliation(s)
- Eric S. Nealy
- Seattle Children’s Research Institute, Seattle WA
- Fred Hutch Cancer Center, Seattle WA
| | | | - Steve M. Adelmund
- Department of Chemical Engineering, University of Washington, Seattle WA
| | - Barry A. Badeau
- Department of Chemical Engineering, University of Washington, Seattle WA
| | - Jared A. Shadish
- Department of Chemical Engineering, University of Washington, Seattle WA
| | - Emily J. Girard
- Seattle Children’s Research Institute, Seattle WA
- Fred Hutch Cancer Center, Seattle WA
| | | | - Andrew J. Mhyre
- Seattle Children’s Research Institute, Seattle WA
- Fred Hutch Cancer Center, Seattle WA
| | - Jason P. Price
- Seattle Children’s Research Institute, Seattle WA
- Fred Hutch Cancer Center, Seattle WA
| | - Surojit Sarkar
- Seattle Children’s Research Institute, Seattle WA
- Department of Pathology, University of Washington, Seattle WA
- Department of Pediatrics, University of Washington, Seattle WA
| | - Vandana Kalia
- Seattle Children’s Research Institute, Seattle WA
- Department of Pediatrics, University of Washington, Seattle WA
| | - Cole A. DeForest
- Department of Chemical Engineering, University of Washington, Seattle WA
- Department of Bioengineering, University of Washington, Seattle WA
- Department of Biochemistry, University of Washington, Seattle WA
- Department of Biology, University of Washington, Seattle WA
- Department of Chemistry, University of Washington, Seattle WA
- Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle WA
- Institute for Protein Design, University of Washington, Seattle WA
| | - James M. Olson
- Seattle Children’s Research Institute, Seattle WA
- Fred Hutch Cancer Center, Seattle WA
- Department of Pharmacology, University of Washington, Seattle WA
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4
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Hagberg KL, Price JP, Yurgel SN, Kahn ML. The Sinorhizobium meliloti Nitrogen Stress Response Changes Radically in the Face of Concurrent Phosphate Stress. Front Microbiol 2022; 13:800146. [PMID: 35154051 PMCID: PMC8829014 DOI: 10.3389/fmicb.2022.800146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/06/2022] [Indexed: 11/13/2022] Open
Abstract
Expression of hundreds of S. meliloti genes changed more than two-fold in response to either nitrogen or phosphate limitation. When these two stresses were applied together, stress responsive gene expression shifted dramatically. In particular, the nitrogen stress response in the presence of phosphate stress had only 30 of about 350 genes in common with the 280 genes that responded to nitrogen stress with adequate phosphate. Expression of sRNAs was also altered in response to these stresses. 82% of genes that responded to nitrogen stress also responded to phosphate stress, including 20 sRNAs. A subset of these sRNAs is known to be chaperoned by the RNA binding protein, Hfq. Hfq had previously been shown to influence about a third of the genes that responded to both nitrogen and phosphate stresses. Phosphate limitation influenced changes in gene expression more than nitrogen limitation and, when both stresses were present, phosphate stress sometimes reversed the direction of some of the changes induced by nitrogen stress. These nutrient stress responses are therefore context dependent.
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Affiliation(s)
- Kelly L. Hagberg
- School of Molecular Biosciences, Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - Jason P. Price
- School of Molecular Biosciences, Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
| | - Svetlana N. Yurgel
- School of Molecular Biosciences, Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
- Department of Plant, Food and Environmental Sciences, Dalhousie University, Truro, NS, Canada
| | - Michael L. Kahn
- School of Molecular Biosciences, Institute of Biological Chemistry, Washington State University, Pullman, WA, United States
- *Correspondence: Michael L. Kahn,
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5
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Ball HA, McWhirter L, Ballard C, Bhome R, Blackburn DJ, Edwards MJ, Fox NC, Howard R, Huntley J, Isaacs JD, Larner AJ, Nicholson TR, Pennington CM, Poole N, Price G, Price JP, Reuber M, Ritchie C, Rossor MN, Schott JM, Venneri A, Stone J, Carson AJ. Reply: Functional cognitive disorder: dementia's blind spot. Brain 2021; 144:e73. [PMID: 34398190 DOI: 10.1093/brain/awab305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Harriet A Ball
- Clinical Neurosciences, University of Bristol, BS10 5NB, UK
| | - Laura McWhirter
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
| | - Clive Ballard
- College of Medicine and Health, University of Exeter, EX1 2LU, UK
| | - Rohan Bhome
- Division of Psychiatry, University College London, W1T 7NF, UK
| | - Daniel J Blackburn
- Department of Neuroscience, Medical School, University of Sheffield, S10 2TN, UK
| | - Mark J Edwards
- Neuroscience research Centre, St George's, University of London, SW17 0RE, UK
| | - Nick C Fox
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, WC1E 6BT, UK
| | - Robert Howard
- Division of Psychiatry, University College London, W1T 7NF, UK
| | | | - Jeremy D Isaacs
- Neuroscience research Centre, St George's, University of London, SW17 0RE, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, SW17 0QT, UK
| | - A J Larner
- Cognitive Function Clinic, Walton Centre for Neurology and Neurosurgery, Liverpool, L9 7LJ, UK
| | - Timothy R Nicholson
- Institute of Psychiatry Psychology & Neuroscience, King's College London, SE5 8AF, UK
| | | | - Norman Poole
- Neuropsychiatry Dept, St George's Hospital, London SW17 0QT, UK
| | - Gary Price
- Department of Neuropsychiatry, The National Hospital for Neurology and Neurosurgery, University College London Hospitals NHS Foundation Trust, London, WC1N 3BG, UK
| | - J P Price
- Department of Neuropsychology, South Tees Hospitals NHS Foundation Trust, James Cook University Hospital, Middlesbrough, TS4 3BW, UK
| | - Markus Reuber
- Department of Neuroscience, Medical School, University of Sheffield, S10 2TN, UK
| | - Craig Ritchie
- Centre for Dementia Prevention, The University of Edinburgh, EH16 4UX, UK
| | - Martin N Rossor
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, WC1E 6BT, UK
| | - Jonathan M Schott
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, WC1E 6BT, UK
| | - Annalena Venneri
- Department of Life Sciences, Brunel University London, UB8 3PH, UK
| | - Jon Stone
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
| | - Alan J Carson
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
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6
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Ball HA, McWhirter L, Ballard C, Bhome R, Blackburn DJ, Edwards MJ, Fleming SM, Fox NC, Howard R, Huntley J, Isaacs JD, Larner AJ, Nicholson TR, Pennington CM, Poole N, Price G, Price JP, Reuber M, Ritchie C, Rossor MN, Schott JM, Teodoro T, Venneri A, Stone J, Carson AJ. Functional cognitive disorder: dementia's blind spot. Brain 2020; 143:2895-2903. [PMID: 32791521 PMCID: PMC7586080 DOI: 10.1093/brain/awaa224] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 05/06/2020] [Accepted: 05/21/2020] [Indexed: 12/25/2022] Open
Abstract
An increasing proportion of cognitive difficulties are recognized to have a functional cause, the chief clinical indicator of which is internal inconsistency. When these symptoms are impairing or distressing, and not better explained by other disorders, this can be conceptualized as a cognitive variant of functional neurological disorder, termed functional cognitive disorder (FCD). FCD is likely very common in clinical practice but may be under-diagnosed. Clinicians in many settings make liberal use of the descriptive term mild cognitive impairment (MCI) for those with cognitive difficulties not impairing enough to qualify as dementia. However, MCI is an aetiology-neutral description, which therefore includes patients with a wide range of underlying causes. Consequently, a proportion of MCI cases are due to non-neurodegenerative processes, including FCD. Indeed, significant numbers of patients diagnosed with MCI do not 'convert' to dementia. The lack of diagnostic specificity for MCI 'non-progressors' is a weakness inherent in framing MCI primarily within a deterministic neurodegenerative pathway. It is recognized that depression, anxiety and behavioural changes can represent a prodrome to neurodegeneration; empirical data are required to explore whether the same might hold for subsets of individuals with FCD. Clinicians and researchers can improve study efficacy and patient outcomes by viewing MCI as a descriptive term with a wide differential diagnosis, including potentially reversible components such as FCD. We present a preliminary definition of functional neurological disorder-cognitive subtype, explain its position in relation to other cognitive diagnoses and emerging biomarkers, highlight clinical features that can lead to positive diagnosis (as opposed to a diagnosis of exclusion), and red flags that should prompt consideration of alternative diagnoses. In the research setting, positive identifiers of FCD will enhance our recognition of individuals who are not in a neurodegenerative prodrome, while greater use of this diagnosis in clinical practice will facilitate personalized interventions.
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Affiliation(s)
- Harriet A Ball
- Population Health Sciences, University of Bristol, BS8 1QU, UK
| | - Laura McWhirter
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
| | - Clive Ballard
- College of Medicine and Health, University of Exeter, EX1 2LU, UK
| | - Rohan Bhome
- Division of Psychiatry, University College London, W1T 7NF, UK
| | - Daniel J Blackburn
- Department of Neuroscience, Medical School, The University of Sheffield, S10 2TN, UK
| | - Mark J Edwards
- Neuroscience Research Centre, St George's, University of London, SW17 0RE, UK
| | - Stephen M Fleming
- Wellcome Centre for Human Neuroimaging, University College London, WC1N 3AR, UK
| | - Nick C Fox
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, WC1E 6BT, UK
| | - Robert Howard
- Division of Psychiatry, University College London, W1T 7NF, UK
| | | | - Jeremy D Isaacs
- Neuroscience Research Centre, St George's, University of London, SW17 0RE, UK.,Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, SW17 0QT, UK
| | - Andrew J Larner
- Cognitive Function Clinic, Walton Centre for Neurology and Neurosurgery, Liverpool, L9 7LJ, UK
| | - Timothy R Nicholson
- Institute of Psychiatry Psychology and Neuroscience, King's College London, SE5 8AF, UK
| | | | - Norman Poole
- Department of Neurology, St George's University Hospitals NHS Foundation Trust, London, SW17 0QT, UK
| | - Gary Price
- University College London Hospitals NHS Foundation Trust, NW1 2BU, UK
| | - Jason P Price
- Department of Neuropsychology, South Tees Hospitals NHS Foundation Trust, TS4 3BW, UK
| | - Markus Reuber
- Department of Neuroscience, Medical School, The University of Sheffield, S10 2TN, UK
| | - Craig Ritchie
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
| | - Martin N Rossor
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, WC1E 6BT, UK
| | - Jonathan M Schott
- Dementia Research Centre, Department of Neurodegenerative Diseases, UCL Queen Square Institute of Neurology, WC1E 6BT, UK
| | - Tiago Teodoro
- Neuroscience Research Centre, St George's, University of London, SW17 0RE, UK.,Instituto de Medicina Molecular, Universidade de Lisbon, 1649-028 Lisboa, Portugal
| | - Annalena Venneri
- Department of Neuroscience, Medical School, The University of Sheffield, S10 2TN, UK
| | - Jon Stone
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
| | - Alan J Carson
- Centre for Clinical Brain Sciences, The University of Edinburgh, EH16 4SB, UK
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7
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Azzaz AM, Vitalini MW, Thomas AS, Price JP, Blacketer MJ, Cryderman DE, Zirbel LN, Woodcock CL, Elcock AH, Wallrath LL, Shogren-Knaak MA. Human heterochromatin protein 1α promotes nucleosome associations that drive chromatin condensation. J Biol Chem 2014; 289:6850-6861. [PMID: 24415761 DOI: 10.1074/jbc.m113.512137] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
HP1(Hsα)-containing heterochromatin is located near centric regions of chromosomes and regulates DNA-mediated processes such as DNA repair and transcription. The higher-order structure of heterochromatin contributes to this regulation, yet the structure of heterochromatin is not well understood. We took a multidisciplinary approach to determine how HP1(Hsα)-nucleosome interactions contribute to the structure of heterochromatin. We show that HP1(Hsα) preferentially binds histone H3K9Me3-containing nucleosomal arrays in favor of non-methylated nucleosomal arrays and that nonspecific DNA interactions and pre-existing chromatin compaction promote binding. The chromo and chromo shadow domains of HP1(Hsα) play an essential role in HP1(Hsα)-nucleosome interactions, whereas the hinge region appears to have a less significant role. Electron microscopy of HP1(Hsα)-associated nucleosomal arrays showed that HP1(Hsα) caused nucleosome associations within an array, facilitating chromatin condensation. Differential sedimentation of HP1(Hsα)-associated nucleosomal arrays showed that HP1(Hsα) promotes interactions between arrays. These strand-to-strand interactions are supported by in vivo studies where tethering the Drosophila homologue HP1a to specific sites promotes interactions with distant chromosomal sites. Our findings demonstrate that HP1(Hsα)-nucleosome interactions cause chromatin condensation, a process that regulates many chromosome events.
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Affiliation(s)
- Abdelhamid M Azzaz
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011
| | | | - Andrew S Thomas
- Department of Biochemistry, University of Iowa, Iowa City, Iowa 52241
| | - Jason P Price
- Department of Biochemistry, University of Iowa, Iowa City, Iowa 52241
| | - Melissa J Blacketer
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011
| | - Diane E Cryderman
- Department of Biochemistry, University of Iowa, Iowa City, Iowa 52241
| | - Luka N Zirbel
- Department of Biochemistry, University of Iowa, Iowa City, Iowa 52241
| | | | - Adrian H Elcock
- Department of Biochemistry, University of Iowa, Iowa City, Iowa 52241
| | - Lori L Wallrath
- Department of Biochemistry, University of Iowa, Iowa City, Iowa 52241.
| | - Michael A Shogren-Knaak
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, Iowa 50011.
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8
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Price JP. The computerized object and abstract designs test (COAD): A pilot study of a new test of visual working memory. British Journal of Clinical Psychology 2010; 48:109-23. [DOI: 10.1348/014466508x366713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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9
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Maury W, Price JP, Brindley MA, Oh C, Neighbors JD, Wiemer DF, Wills N, Carpenter S, Hauck C, Murphy P, Widrlechner MP, Delate K, Kumar G, Kraus GA, Rizshsky L, Nikolau B. Identification of light-independent inhibition of human immunodeficiency virus-1 infection through bioguided fractionation of Hypericum perforatum. Virol J 2009; 6:101. [PMID: 19594941 PMCID: PMC2716326 DOI: 10.1186/1743-422x-6-101] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2009] [Accepted: 07/13/2009] [Indexed: 11/29/2022] Open
Abstract
Background Light-dependent activities against enveloped viruses in St. John's Wort (Hypericum perforatum) extracts have been extensively studied. In contrast, light-independent antiviral activity from this species has not been investigated. Results Here, we identify the light-independent inhibition of human immunodeficiency virus-1 (HIV-1) by highly purified fractions of chloroform extracts of H. perforatum. Both cytotoxicity and antiviral activity were evident in initial chloroform extracts, but bioassay-guided fractionation produced fractions that inhibited HIV-1 with little to no cytotoxicity. Separation of these two biological activities has not been reported for constituents responsible for the light-dependent antiviral activities. Antiviral activity was associated with more polar subfractions. GC/MS analysis of the two most active subfractions identified 3-hydroxy lauric acid as predominant in one fraction and 3-hydroxy myristic acid as predominant in the other. Synthetic 3-hydroxy lauric acid inhibited HIV infectivity without cytotoxicity, suggesting that this modified fatty acid is likely responsible for observed antiviral activity present in that fraction. As production of 3-hydroxy fatty acids by plants remains controversial, H. perforatum seedlings were grown sterilely and evaluated for presence of 3-hydroxy fatty acids by GC/MS. Small quantities of some 3-hydroxy fatty acids were detected in sterile plants, whereas different 3-hydroxy fatty acids were detected in our chloroform extracts or field-grown material. Conclusion Through bioguided fractionation, we have identified that 3-hydroxy lauric acid found in field grown Hypericum perforatum has anti-HIV activity. This novel anti-HIV activity can be potentially developed into inexpensive therapies, expanding the current arsenal of anti-retroviral agents.
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Affiliation(s)
- Wendy Maury
- Department of Microbiology, University of Iowa, Iowa City, IA 52242, USA.
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10
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Birt DF, Widrlechner MP, Hammer KDP, Hillwig ML, Wei J, Kraus GA, Murphy PA, McCoy J, Wurtele ES, Neighbors JD, Wiemer DF, Maury WJ, Price JP. Hypericum in infection: Identification of anti-viral and anti-inflammatory constituents. Pharm Biol 2009; 47:774-782. [PMID: 19907671 PMCID: PMC2774925 DOI: 10.1080/13880200902988645] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The Iowa Center for Research on Botanical Dietary Supplements seeks to optimize Echinacea, Hypericum, and Prunella botanical supplements for human-health benefit, emphasizing antiviral, anti-inflammatory and anti-pain activities. This mini-review reports on ongoing studies on Hypericum. The Center uses the genetically diverse, well-documented Hypericum populations collected and maintained at the USDA-ARS North Central Regional Plant Introduction Station (NCRPIS), and the strength of research in synthetic chemistry at Iowa State University to tap natural diversity, to help discover key constituents and interactions among constituents that impact bioactivity and toxicity. The NCRPIS has acquired more than 180 distinct populations of Hypericum, with a focus on Hypericum perforatum L. (Hypericaceae), representing about 13% of currently recognized taxa. Center chemists have developed novel synthetic pathways for key flavones, acyl phloroglucinols, hyperolactones and a tetralin that have been found in Hypericum, and these compounds are used as standards and for bioactivity studies. Both light-dependent and light-independent anti-viral activities have been identified by using bioactivity-guided fractionation of H. perforatum and a HIV-1 infection test system. Our Center has focused on light-independent activity, potentially due to novel chemicals, and polar fractions are undergoing further fractionation. Anti-inflammatory activity has been found to be light-independent, and fractionation of a flavonoid-rich extract revealed four compounds (amentoflavone, chlorogenic acid, pseudohypericin and quercetin) that interacted in the light to inhibit lipopolysaccharide-induced prostaglandin E(2) activity. The Center continues to explore novel populations of H. perforatum and related species to identify constituents and interactions of constituents that contribute to potential health benefits related to infection.
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Affiliation(s)
- Diane F Birt
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA
- Corresponding author: Diane F Birt, Department of Food Science and Human Nutrition, Iowa State University, 215 MacKay Hall, Ames, IA 50011. Tel: (515) 294-9873. Fax: 515-294-6193.
| | - Mark P Widrlechner
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Departments of Horticulture and Agronomy, Iowa State University, Ames, IA
- US Department of Agriculture-Agricultural Research Service, North Central Regional Plant Introduction Station, Ames, IA
| | - Kimberly DP Hammer
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA
- Interdepartmental Genetics Graduate Program, Iowa State University, Ames, IA
| | - Matthew L Hillwig
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA
| | - Jingqiang Wei
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Chemistry, Iowa State University, Ames, IA
| | - George A Kraus
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Chemistry, Iowa State University, Ames, IA
| | - Patricia A Murphy
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Food Science and Human Nutrition, Iowa State University, Ames, IA
| | - JoeAnn McCoy
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- US Department of Agriculture-Agricultural Research Service, North Central Regional Plant Introduction Station, Ames, IA
| | - Eve S Wurtele
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, IA
| | - Jeffrey D Neighbors
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Chemistry, University of Iowa, Iowa City, IA
| | - David F Wiemer
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Chemistry, University of Iowa, Iowa City, IA
| | - Wendy J Maury
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Microbiology, University of Iowa, Iowa City, IA
| | - Jason P Price
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA
- Department of Microbiology, University of Iowa, Iowa City, IA
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11
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Birt DF, Widrlechner MP, Lalone CA, Wu L, Bae J, Solco AK, Kraus GA, Murphy PA, Wurtele ES, Leng Q, Hebert SC, Maury WJ, Price JP. Echinacea in infection. Am J Clin Nutr 2008; 87:488S-92S. [PMID: 18258644 PMCID: PMC2262947 DOI: 10.1093/ajcn/87.2.488s] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Ongoing studies have developed strategies for identifying key bioactive compounds and chemical profiles in Echinacea with the goal of improving its human health benefits. Antiviral and antiinflammatory-antipain assays have targeted various classes of chemicals responsible for these activities. Analysis of polar fractions of E. purpurea extracts showed the presence of antiviral activity, with evidence suggesting that polyphenolic compounds other than the known HIV inhibitor, cichoric acid, may be involved. Antiinflammatory activity differed by species, with E. sanguinea having the greatest activity and E. angustifolia, E. pallida, and E. simulata having somewhat less. Fractionation and studies with pure compounds indicate that this activity is explained, at least in part, by the alkamide constituents. Ethanol extracts from Echinacea roots had potent activity as novel agonists of TRPV1, a mammalian pain receptor reported as an integrator of inflammatory pain and hyperalgesia and a prime therapeutic target for analgesic and antiinflammatory drugs. One fraction from E. purpurea ethanol extract was bioactive in this system. Interestingly, the antiinflammatory compounds identified to inhibit prostaglandin E(2) production differed from those involved in TRPV1 receptor activation.
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Affiliation(s)
- Diane F Birt
- The Center for Research on Botanical Dietary Supplements, Iowa State University, Ames, IA 50011, USA.
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12
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Abstract
OBJECTIVE To identify specific ego defences and core schemas involved in post-traumatic stress disorder (PTSD) symptomatology. DESIGN Stepwise regression with predictor models generated from ego defences and core schema variables. METHOD Seventy-seven participants completed the Impact of Event Scale, the 40-item Defence Style Questionnaire and the Young Schema Questionnaire (short-form). RESULTS Four core schemas (Defectiveness, Dependency, Enmeshment and Failure) and three defence mechanisms (Splitting, Rationalization and Projection) were found to be significant predictors in PTSD symptomatology. CONCLUSIONS The identified core schema and ego defences are seen to be theoretically consistent with present cognitive and psychodynamic conceptualizations of PTSD. The implications for future research are discussed.
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Biglione S, Byers SA, Price JP, Nguyen VT, Bensaude O, Price DH, Maury W. Inhibition of HIV-1 replication by P-TEFb inhibitors DRB, seliciclib and flavopiridol correlates with release of free P-TEFb from the large, inactive form of the complex. Retrovirology 2007; 4:47. [PMID: 17625008 PMCID: PMC1948018 DOI: 10.1186/1742-4690-4-47] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 07/11/2007] [Indexed: 01/07/2023] Open
Abstract
Background The positive transcription elongation factor, P-TEFb, comprised of cyclin dependent kinase 9 (Cdk9) and cyclin T1, T2 or K regulates the productive elongation phase of RNA polymerase II (Pol II) dependent transcription of cellular and integrated viral genes. P-TEFb containing cyclin T1 is recruited to the HIV long terminal repeat (LTR) by binding to HIV Tat which in turn binds to the nascent HIV transcript. Within the cell, P-TEFb exists as a kinase-active, free form and a larger, kinase-inactive form that is believed to serve as a reservoir for the smaller form. Results We developed a method to rapidly quantitate the relative amounts of the two forms based on differential nuclear extraction. Using this technique, we found that titration of the P-TEFb inhibitors flavopiridol, DRB and seliciclib onto HeLa cells that support HIV replication led to a dose dependent loss of the large form of P-TEFb. Importantly, the reduction in the large form correlated with a reduction in HIV-1 replication such that when 50% of the large form was gone, HIV-1 replication was reduced by 50%. Some of the compounds were able to effectively block HIV replication without having a significant impact on cell viability. The most effective P-TEFb inhibitor flavopiridol was evaluated against HIV-1 in the physiologically relevant cell types, peripheral blood lymphocytes (PBLs) and monocyte derived macrophages (MDMs). Flavopiridol was found to have a smaller therapeutic index (LD50/IC50) in long term HIV-1 infectivity studies in primary cells due to greater cytotoxicity and reduced efficacy at blocking HIV-1 replication. Conclusion Initial short term studies with P-TEFb inhibitors demonstrated a dose dependent loss of the large form of P-TEFb within the cell and a concomitant reduction in HIV-1 infectivity without significant cytotoxicity. These findings suggested that inhibitors of P-TEFb may serve as effective anti-HIV-1 therapies. However, longer term HIV-1 replication studies indicated that these inhibitors were more cytotoxic and less efficacious against HIV-1 in the primary cell cultures.
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Affiliation(s)
- Sebastian Biglione
- Interdisciplinary Molecular and Cellular Biology Program, University of Iowa, Iowa City, IA, USA
- CBR Institute for Biomedical Research, Harvard Medical School, Boston, MA, 02115, USA
| | - Sarah A Byers
- Interdisciplinary Molecular and Cellular Biology Program, University of Iowa, Iowa City, IA, USA
- Oregon Health & Science University, Department of Molecular and Medical Genetics, Portland, OR 97239, USA
| | - Jason P Price
- Department of Microbiology, University of Iowa, Iowa City, IA, USA
| | - Van Trung Nguyen
- Laboratoire de Regulation de l'Expression Genetique, Ecole Normale Superieure, Paris, France
| | - Olivier Bensaude
- Laboratoire de Regulation de l'Expression Genetique, Ecole Normale Superieure, Paris, France
| | - David H Price
- Interdisciplinary Molecular and Cellular Biology Program, University of Iowa, Iowa City, IA, USA
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - Wendy Maury
- Interdisciplinary Molecular and Cellular Biology Program, University of Iowa, Iowa City, IA, USA
- Department of Microbiology, University of Iowa, Iowa City, IA, USA
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14
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Sedore SC, Byers SA, Biglione S, Price JP, Maury WJ, Price DH. Manipulation of P-TEFb control machinery by HIV: recruitment of P-TEFb from the large form by Tat and binding of HEXIM1 to TAR. Nucleic Acids Res 2007; 35:4347-58. [PMID: 17576689 PMCID: PMC1935001 DOI: 10.1093/nar/gkm443] [Citation(s) in RCA: 120] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Basal transcription of the HIV LTR is highly repressed and requires Tat to recruit the positive transcription elongation factor, P-TEFb, which functions to promote the transition of RNA polymerase II from abortive to productive elongation. P-TEFb is found in two forms in cells, a free, active form and a large, inactive complex that also contains 7SK RNA and HEXIM1 or HEXIM2. Here we show that HIV infection of cells led to the release of P-TEFb from the large form. Consistent with Tat being the cause of this effect, transfection of a FLAG-tagged Tat in 293T cells caused a dramatic shift of P-TEFb out of the large form to a smaller form containing Tat. In vitro, Tat competed with HEXIM1 for binding to 7SK, blocked the formation of the P-TEFb–HEXIM1–7SK complex, and caused the release P-TEFb from a pre-formed P-TEFb–HEXIM1–7SK complex. These findings indicate that Tat can acquire P-TEFb from the large form. In addition, we found that HEXIM1 binds tightly to the HIV 5′ UTR containing TAR and recruits and inhibits P-TEFb activity. This suggests that in the absence of Tat, HEXIM1 may bind to TAR and repress transcription elongation of the HIV LTR.
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Affiliation(s)
- Stanley C. Sedore
- Department of Biochemistry, Department of Microbiology, Medical Scientist Training Program and Interdisciplinary Molecular Biology Program, University of Iowa, Iowa City, IA, USA
| | - Sarah A. Byers
- Department of Biochemistry, Department of Microbiology, Medical Scientist Training Program and Interdisciplinary Molecular Biology Program, University of Iowa, Iowa City, IA, USA
| | - Sebastian Biglione
- Department of Biochemistry, Department of Microbiology, Medical Scientist Training Program and Interdisciplinary Molecular Biology Program, University of Iowa, Iowa City, IA, USA
| | - Jason P. Price
- Department of Biochemistry, Department of Microbiology, Medical Scientist Training Program and Interdisciplinary Molecular Biology Program, University of Iowa, Iowa City, IA, USA
| | - Wendy J. Maury
- Department of Biochemistry, Department of Microbiology, Medical Scientist Training Program and Interdisciplinary Molecular Biology Program, University of Iowa, Iowa City, IA, USA
| | - David H. Price
- Department of Biochemistry, Department of Microbiology, Medical Scientist Training Program and Interdisciplinary Molecular Biology Program, University of Iowa, Iowa City, IA, USA
- *To whom correspondence should be addressed. +1 319 335 7910+1 319 384 4770
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15
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Barboric M, Kohoutek J, Price JP, Blazek D, Price DH, Peterlin BM. Interplay between 7SK snRNA and oppositely charged regions in HEXIM1 direct the inhibition of P-TEFb. EMBO J 2005; 24:4291-303. [PMID: 16362050 PMCID: PMC1356324 DOI: 10.1038/sj.emboj.7600883] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2005] [Accepted: 11/02/2005] [Indexed: 11/09/2022] Open
Abstract
Transcription elongation of eukaryotic genes by RNA polymerase II depends on the positive transcription elongation factor b (P-TEFb). When sequestered into the large complex, P-TEFb kinase activity is inhibited by the coordinate actions of 7SK small nuclear RNA (7SK snRNA) and hexamethylene bisacetamide (HMBA)-induced protein 1 (HEXIM1). We found that the basic region in HEXIM1 directs its nuclear import via two monopartite and two bipartite nuclear localization sequences. Moreover, the arginine-rich motif within it is essential for its binding to 7SK snRNA, P-TEFb, and inhibition of transcription. Notably, the basic region interacts with the adjacent acidic regions in the absence of RNA. The removal of the positive or negative charges from these regions in HEXIM1 leads to its sequestration into the large complex and inhibition of transcription independently of the arginine-rich motif. Finally, the removal of the negative charges from HEXIM1 results in its subnuclear localization into nuclear speckles. We propose a model where the interplay between 7SK snRNA and oppositely charged regions in HEXIM1 direct its binding to P-TEFb and subcellular localization that culminates in the inhibition of transcription.
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MESH Headings
- Acetamides/chemistry
- Active Transport, Cell Nucleus
- Amino Acid Motifs
- Amino Acid Sequence
- Animals
- Arginine/chemistry
- Bacterial Proteins/metabolism
- Blotting, Western
- Cell Nucleus/metabolism
- Centrifugation, Density Gradient
- Chloramphenicol O-Acetyltransferase/metabolism
- Genes, Reporter
- Glutathione Transferase/metabolism
- Glycerol/pharmacology
- HeLa Cells
- Humans
- Immunoprecipitation
- Luminescent Proteins/metabolism
- Microscopy, Confocal
- Microscopy, Fluorescence
- Molecular Sequence Data
- Plasmids/metabolism
- Positive Transcriptional Elongation Factor B/metabolism
- Protein Binding
- Protein Structure, Tertiary
- RNA/chemistry
- RNA Polymerase II/metabolism
- RNA, Small Nuclear/metabolism
- RNA-Binding Proteins/metabolism
- Sequence Homology, Amino Acid
- Transcription Factors
- Transcription, Genetic
- Transfection
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Affiliation(s)
- Matjaz Barboric
- Departments of Medicine, Microbiology, and Immunology, Rosalind Russell Medical Research Center, University of California at San Francisco, San Francisco, CA, USA
| | - Jiří Kohoutek
- Departments of Medicine, Microbiology, and Immunology, Rosalind Russell Medical Research Center, University of California at San Francisco, San Francisco, CA, USA
| | - Jason P Price
- Department of Biochemistry, University of Iowa, Iowa City, Iowa, USA
| | - Dalibor Blazek
- Departments of Medicine, Microbiology, and Immunology, Rosalind Russell Medical Research Center, University of California at San Francisco, San Francisco, CA, USA
| | - David H Price
- Department of Biochemistry, University of Iowa, Iowa City, Iowa, USA
| | - B Matija Peterlin
- Departments of Medicine, Microbiology, and Immunology, Rosalind Russell Medical Research Center, University of California at San Francisco, San Francisco, CA, USA
- Box 0703, 3rd and Parnassus Aves, San Francisco, CA 94143-0703, USA. Tel.: +1 415 502 1902; Fax: +1 415 502 1901; E-mail:
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16
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Li Q, Price JP, Byers SA, Cheng D, Peng J, Price DH. Analysis of the large inactive P-TEFb complex indicates that it contains one 7SK molecule, a dimer of HEXIM1 or HEXIM2, and two P-TEFb molecules containing Cdk9 phosphorylated at threonine 186. J Biol Chem 2005; 280:28819-26. [PMID: 15965233 DOI: 10.1074/jbc.m502712200] [Citation(s) in RCA: 159] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Positive transcription elongation factor b (P-TEFb) regulates eukaryotic gene expression at the level of elongation, and is itself controlled by the reversible association of 7SK RNA and an RNA-binding protein, HEXIM1 or HEXIM2. To further understand how P-TEFb is regulated, we analyzed the stoichiometry of all the known components of the large, inactive P-TEFb complex. Mutational analyses of a putative coiled coil region in the carboxyl-terminal portion of HEXIM1 revealed that the protein is a dimer in solution and remains a dimer after binding to 7SK. Although a HEXIM1 dimer contains two potential RNA binding motifs and ultimately recruits two P-TEFb molecules, it associates with only one molecule of RNA. The first 172 nucleotides of the 330-nucleotide 7SK are sufficient to bind HEXIM1 or HEXIM2, and then recruit and inhibit P-TEFb. Deletion of the first 121 amino acids of HEXIM1 allowed it to inhibit P-TEFb partially in the absence of 7SK RNA. Mutation of a conserved tyrosine (Tyr(271) in HEXIM1) to alanine or glutamate or mutation of a conserved phenylalanine (Phe(208)) to alanine, aspartate, or lysine, resulted in loss of inhibition of P-TEFb, but did not affect formation of the 7SK.HEXIM.P-TEFb complex. Analysis of T-loop phosphorylation in Cdk9 indicated that phosphorylation of Thr(186), but not Ser(175), was essential for kinase activity and for recruitment of P-TEFb to the 7SK.HEXIM complex. A model illustrates what is currently known about how HEXIM proteins, 7SK, and P-TEFb assemble to maintain an activated kinase in a readily available, but inactive form.
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Affiliation(s)
- Qintong Li
- Department of Biochemistry and Molecular Biology Program, University of Iowa, Iowa City, Iowa 52242, USA
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17
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Byers SA, Price JP, Cooper JJ, Li Q, Price DH. HEXIM2, a HEXIM1-related protein, regulates positive transcription elongation factor b through association with 7SK. J Biol Chem 2005; 280:16360-7. [PMID: 15713662 DOI: 10.1074/jbc.m500424200] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The kinase activity of positive transcription elongation factor b (P-TEFb), composed of cyclin-dependent kinase 9 and cyclin T1 or T2, is required for the transition of RNA polymerase II into productive elongation. P-TEFb activity has been shown to be negatively regulated by association with the small nuclear RNA 7SK and the HEXIM1 protein. Here, we characterize HEXIM2, a previously predicted protein with sequence similarity to HEXIM1. HEXIM2 is expressed in HeLa and Jurkat cells, and glycerol gradient analysis and immunoprecipitations indicate that HEXIM2, like HEXIM1, has a regulated association with P-TEFb. As HEXIM1 is knocked down, HEXIM2 functionally compensates for its association with P-TEFb. Electrophoretic mobility shift assays and in vitro kinase assays demonstrate that HEXIM2 forms complexes containing 7SK and P-TEFb and, in conjunction with 7SK, inhibits P-TEFb kinase activity. Our results provide strong evidence that HEXIM2 is a regulator of P-TEFb function. Furthermore, our results support the idea that the utilization of HEXIM1 or HEXIM2 to bind and inhibit P-TEFb can be differentially regulated in vivo.
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Affiliation(s)
- Sarah A Byers
- Molecular Biology Program and Department of Biochemistry, University of Iowa, Iowa City, Iowa 52242, USA
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18
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Michels AA, Fraldi A, Li Q, Adamson TE, Bonnet F, Nguyen VT, Sedore SC, Price JP, Price DH, Lania L, Bensaude O. Binding of the 7SK snRNA turns the HEXIM1 protein into a P-TEFb (CDK9/cyclin T) inhibitor. EMBO J 2004; 23:2608-19. [PMID: 15201869 PMCID: PMC449783 DOI: 10.1038/sj.emboj.7600275] [Citation(s) in RCA: 233] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2003] [Accepted: 05/24/2004] [Indexed: 11/08/2022] Open
Abstract
The positive transcription elongation factor b (P-TEFb) plays a pivotal role in productive elongation of nascent RNA molecules by RNA polymerase II. Core active P-TEFb is composed of CDK9 and cyclin T. In addition, mammalian cell extracts contain an inactive P-TEFb complex composed of four components, CDK9, cyclin T, the 7SK snRNA and the MAQ1/HEXIM1 protein. We now report an in vitro reconstitution of 7SK-dependent HEXIM1 association to purified P-TEFb and subsequent CDK9 inhibition. Yeast three-hybrid tests and gel-shift assays indicated that HEXIM1 binds 7SK snRNA directly and a 7SK snRNA-recognition motif was identified in the central part of HEXIM1 (amino acids (aa) 152-155). Data from yeast two-hybrid and pull-down assay on GST fusion proteins converge to a direct binding of P-TEFb to the HEXIM1 C-terminal domain (aa 181-359). Consistently, point mutations in an evolutionarily conserved motif (aa 202-205) were found to suppress P-TEFb binding and inhibition without affecting 7SK recognition. We propose that the RNA-binding domain of HEXIM1 mediates its association with 7SK and that P-TEFb then enters the complex through association with HEXIM1.
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Affiliation(s)
- Annemieke A Michels
- UMR 8541 CNRS, Ecole Normale Supérieure, Régulation de l'Expression Génétique, Paris, France
| | - Alessandro Fraldi
- Dipartimento di Genetica, Biologia Generale e Molecolare, Università di Napoli ‘Federico II', Napoli, Italy
| | - Qintong Li
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - Todd E Adamson
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - François Bonnet
- UMR 8541 CNRS, Ecole Normale Supérieure, Régulation de l'Expression Génétique, Paris, France
| | - Van Trung Nguyen
- UMR 8541 CNRS, Ecole Normale Supérieure, Régulation de l'Expression Génétique, Paris, France
| | - Stanley C Sedore
- Medical Scientist Training Program, University of Iowa, Iowa City, IA, USA
| | - Jason P Price
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - David H Price
- Department of Biochemistry, University of Iowa, Iowa City, IA, USA
| | - Luigi Lania
- Dipartimento di Genetica, Biologia Generale e Molecolare, Università di Napoli ‘Federico II', Napoli, Italy
| | - Olivier Bensaude
- UMR 8541 CNRS, Ecole Normale Supérieure, Régulation de l'Expression Génétique, Paris, France
- Laboratoire de Régulation de l'Expression Génétique, UMR 8541 CNRS, Ecole Normale Supérieure, 46, rue d Ulm, 75230 Paris Cedex 05, France. Tel.: +33 1 4432 3410; Fax: +33 1 4432 3941; E-mail:
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19
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Abstract
The benign superior vena cava syndrome is an uncommon medical emergency. We describe a case of the superior vena cava syndrome caused by suppurative mediastinal lymphadenitis. The organisms isolated from various cultures were group C beta-hemolytic Streptococcus, Fusobacterium species, Corynebacterium species, Eikenella corrodens, and Streptococcus milleri. These anaerobic bacteria are part of the normal flora of the upper respiratory tract and the oral cavity. Anterior mediastinoscopy through the right parasternal approach was used to drain the anterior mediastinal abscess and to establish the etiologic factor.
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Affiliation(s)
- D Roy
- Department of Internal Medicine, Providence Hospital, Southfield, Michigan, USA
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20
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Abstract
The trauma coordinator (TC) position is a vital link in the development and operations of trauma care systems. In 1992 and 1993, the American Trauma Society conducted a national survey of TCs to describe the roles and characteristics of the persons who hold those positions. Of 354 trauma coordinators identified in 46 states, more than three-fourths were employed by large hospitals designated as trauma centers. The typical TC was a woman 26 to 59 years old who held at least a bachelor's degree in nursing. Although new as TCs (mean, 3 years as TCs), the respondents averaged 14 years experience in nursing. Both full-time and part-time TCs worked longer hours than scheduled, often had supervisory responsibilities, and generally were in the nursing administration or the emergency department structure. Most TCs worked with computerized trauma registries that were used routinely in quality of care reviews.
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Affiliation(s)
- D I Gantt
- National Center for Injury Prevention and Control, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
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Hendrick CA, Johnson LK, Tomes NJ, Smiley BK, Price JP. Insertion of Tn916 into Bacillus pumilus plasmid pMGD302 and evidence for plasmid transfer by conjugation. Plasmid 1991; 26:1-9. [PMID: 1658832 DOI: 10.1016/0147-619x(91)90031-q] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
As part of an effort to develop systems for genetic analysis of strains of Bacillus pumilus which are being used as a microbial hay preservative, we introduced the conjugative Enterococcus faecalis transposon Tn916 into B. pumilus ATCC 1 and two naturally occurring hay isolates of B. pumilus. B. pumilus transconjugants resistant to tetracycline were detected at a frequency of approximately 6.5 x 10(-7) per recipient after filter mating with E. faecalis CG110. Southern hybridization confirmed the insertion of Tn916 into several different sites in the B. pumilus chromosome. Transfer of Tn916 also was observed between strains of B. pumilus in filter matings, and one donor strain transferred tetracycline resistance to recipients in broth matings at high frequency (up to 3.4 x 10(-5) per recipient). Transfer from this donor strain in broth matings was DNase-resistant and was not mediated by culture filtrates. Transconjugants from these broth matings contained derivatives of a cryptic plasmid (pMGD302, approx 60 kb) from the donor strain with Tn916 inserted at various sites. The plasmids containing Tn916 insertions transferred to a B. pumilus recipient strain at frequencies of approx 5 x 10(-6) per recipient. This evidence suggests that pMGD302 can transfer by a process resembling conjugation between strains of B. pumilus.
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Affiliation(s)
- C A Hendrick
- Microbial Genetics, Division of Pioneer Hi-Bred International, Inc., Johnston, Iowa 50131
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Santanello SA, Price JP, Herron H, Falcone RE. The risk of AIDS-virus exposure during aeromedical transport of trauma patients. Emerg Med Serv 1990; 19:48, 80. [PMID: 10105154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Price JP, Falcone RE. Diminishing organ donors. Ohio Med 1990; 86:251-2. [PMID: 2360949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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Abstract
In recent years jet injection of insulin has been widely used by patients with diabetes mellitus. Jet injectors may become contaminated by bacteria because of repeated use without cleaning; cleansing every 2 weeks is recommended. We investigated the occurrence of bacterial contamination by culturing jet injectors in everyday use by 19 patients with diabetes. Swabs from the interior chambers were cultured on blood agar plates. Only one of 20 cultures yielded bacterial growth, and the organism recovered was a presumed contaminant that could not be identified as any common pathogen. No study patient, nor any of more than 70 patients whom we instructed in jet injection, showed any clinical evidence of infection attributable to jet injector use. Jet injectors are unlikely to become colonized by bacteria or to cause infection in patients using them for insulin administration. The low rate of colonization may be due to the antibacterial preservatives added to commercial preparations of insulin. Additional data based on larger numbers of patients would be useful in further clarifying the risk of infection associated with jet injectors.
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Affiliation(s)
- J P Price
- Department of Internal Medicine, Henry Ford Hospital, Detroit, MI 48202
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Price JP. Trauma nurse coordinator. Crit Care Nurse 1988; 8:87-90. [PMID: 3383595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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Price JP. Recent developments in Parkinson's disease. Australas Nurses J 1971; 5:2. [PMID: 5210353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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Bock OA, Marais JS, Price JP. Rectal cancer from axle grease? Br Med J 1970; 1:233-4. [PMID: 5412955 PMCID: PMC1699265 DOI: 10.1136/bmj.1.5690.233-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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Price JP, O'Bryan EC. Malnutrition in South Carolina. As seen by practicing physicians. J S C Med Assoc 1969; 65:111-3. [PMID: 5252628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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