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  1. Article ; Online: Mathematical modeling of N-803 treatment in SIV-infected non-human primates.

    Cody, Jonathan W / Ellis-Connell, Amy L / O'Connor, Shelby L / Pienaar, Elsje

    PLoS computational biology

    2021  Volume 17, Issue 7, Page(s) e1009204

    Abstract: ... In one study, an IL-15 superagonist, N-803, suppressed Simian Immunodeficiency Virus (SIV) in non-human ... with continued N-803 treatment, partially returning after long treatment interruption. While there is evidence ... of these mechanisms to the observed viral dynamics have not been quantified. Here, we utilize mathematical models of N ...

    Abstract Immunomodulatory drugs could contribute to a functional cure for Human Immunodeficiency Virus (HIV). Interleukin-15 (IL-15) promotes expansion and activation of CD8+ T cell and natural killer (NK) cell populations. In one study, an IL-15 superagonist, N-803, suppressed Simian Immunodeficiency Virus (SIV) in non-human primates (NHPs) who had received prior SIV vaccination. However, viral suppression attenuated with continued N-803 treatment, partially returning after long treatment interruption. While there is evidence of concurrent drug tolerance, immune regulation, and viral escape, the relative contributions of these mechanisms to the observed viral dynamics have not been quantified. Here, we utilize mathematical models of N-803 treatment in SIV-infected macaques to estimate contributions of these three key mechanisms to treatment outcomes: 1) drug tolerance, 2) immune regulation, and 3) viral escape. We calibrated our model to viral and lymphocyte responses from the above-mentioned NHP study. Our models track CD8+ T cell and NK cell populations with N-803-dependent proliferation and activation, as well as viral dynamics in response to these immune cell populations. We compared mathematical models with different combinations of the three key mechanisms based on Akaike Information Criterion and important qualitative features of the NHP data. Two minimal models were capable of reproducing the observed SIV response to N-803. In both models, immune regulation strongly reduced cytotoxic cell activation to enable viral rebound. Either long-term drug tolerance or viral escape (or some combination thereof) could account for changes to viral dynamics across long breaks in N-803 treatment. Theoretical explorations with the models showed that less-frequent N-803 dosing and concurrent immune regulation blockade (e.g. PD-L1 inhibition) may improve N-803 efficacy. However, N-803 may need to be combined with other immune therapies to countermand viral escape from the CD8+ T cell response. Our mechanistic model will inform such therapy design and guide future studies.
    MeSH term(s) Animals ; CD8-Positive T-Lymphocytes/immunology ; Computational Biology ; Humans ; Immune Tolerance ; Interleukin-15/agonists ; Killer Cells, Natural/immunology ; Macaca mulatta ; Mathematical Concepts ; Models, Biological ; Recombinant Fusion Proteins/therapeutic use ; Simian Acquired Immunodeficiency Syndrome/immunology ; Simian Acquired Immunodeficiency Syndrome/therapy ; Simian Acquired Immunodeficiency Syndrome/virology ; Simian Immunodeficiency Virus/immunology ; Simian Immunodeficiency Virus/pathogenicity ; Simian Immunodeficiency Virus/physiology ; Viral Load ; Virus Replication
    Chemical Substances ALT-803 ; IL15 protein, human ; Interleukin-15 ; Recombinant Fusion Proteins
    Language English
    Publishing date 2021-07-28
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural ; Research Support, Non-U.S. Gov't
    ZDB-ID 2193340-6
    ISSN 1553-7358 ; 1553-734X
    ISSN (online) 1553-7358
    ISSN 1553-734X
    DOI 10.1371/journal.pcbi.1009204
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Analysis of Hendra Virus Fusion Protein N-Terminal Transmembrane Residues.

    Barrett, Chelsea T / Neal, Hadley E / Edmonds, Kearstin / Zamora, J Lizbeth Reyes / Moncman, Carole L / Popa, Andreea / Smith, Everett Clinton / Webb, Stacy R / Dutch, Rebecca Ellis

    Viruses

    2021  Volume 13, Issue 12

    Abstract: ... mutagenesis to explore the residues in the N-terminus of this region (residues 487-506). In addition ...

    Abstract Hendra virus (HeV) is a zoonotic enveloped member of the family Paramyoxviridae. To successfully infect a host cell, HeV utilizes two surface glycoproteins: the attachment (G) protein to bind, and the trimeric fusion (F) protein to merge the viral envelope with the membrane of the host cell. The transmembrane (TM) region of HeV F has been shown to have roles in F protein stability and the overall trimeric association of F. Previously, alanine scanning mutagenesis has been performed on the C-terminal end of the protein, revealing the importance of β-branched residues in this region. Additionally, residues S490 and Y498 have been demonstrated to be important for F protein endocytosis, needed for the proteolytic processing of F required for fusion. To complete the analysis of the HeV F TM, we performed alanine scanning mutagenesis to explore the residues in the N-terminus of this region (residues 487-506). In addition to confirming the critical roles for S490 and Y498, we demonstrate that mutations at residues M491 and L492 alter F protein function, suggesting a role for these residues in the fusion process.
    MeSH term(s) Alanine/genetics ; Amino Acid Sequence ; Amino Acid Substitution ; Animals ; Cell Membrane/metabolism ; Chlorocebus aethiops ; Endocytosis ; Endosomes/metabolism ; Genes, Reporter ; Hendra Virus/genetics ; Hendra Virus/physiology ; Henipavirus Infections/virology ; Humans ; Membrane Fusion ; Mutagenesis, Site-Directed ; Protein Domains ; Protein Stability ; Vero Cells ; Viral Fusion Proteins/genetics ; Viral Fusion Proteins/metabolism
    Chemical Substances Viral Fusion Proteins ; Alanine (OF5P57N2ZX)
    Language English
    Publishing date 2021-11-24
    Publishing country Switzerland
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 2516098-9
    ISSN 1999-4915 ; 1999-4915
    ISSN (online) 1999-4915
    ISSN 1999-4915
    DOI 10.3390/v13122353
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: IL-15 Superagonist N-803 Enhances IFN-γ Production of MAIT Cells in SIV

    Ellis-Connell, Amy L / Balgeman, Alexis J / Kannal, Nadean M / Hansen Chaimson, Karigynn / Batchenkova, Anna / Safrit, Jeffrey T / O'Connor, Shelby L

    Infection and immunity

    2022  Volume 90, Issue 10, Page(s) e0025922

    Abstract: ... of an immunotherapeutic agent, the IL-15 superagonist N-803, on MAIT cell activation, trafficking, and cytolytic function ... in macaques. We found that N-803 could activate MAIT cells in vitro and increase their ability to produce IFN ...

    Abstract Mucosal associated invariant T (MAIT) cells are innate T cells that recognize bacterial metabolites and secrete cytokines and cytolytic enzymes to destroy infected target cells. This makes MAIT cells promising targets for immunotherapy to combat bacterial infections. Here, we analyzed the effects of an immunotherapeutic agent, the IL-15 superagonist N-803, on MAIT cell activation, trafficking, and cytolytic function in macaques. We found that N-803 could activate MAIT cells in vitro and increase their ability to produce IFN-γ in response to bacterial stimulation. To expand upon this, we examined the phenotypes and functions of MAIT cells present in samples collected from PBMC, airways (bronchoalveolar lavage [BAL] fluid), and lymph nodes (LN) from rhesus macaques that were treated
    MeSH term(s) Animals ; Mucosal-Associated Invariant T Cells ; Granzymes ; Macaca mulatta ; Leukocytes, Mononuclear ; Ki-67 Antigen ; Interferon-gamma
    Chemical Substances ALT-803 ; Granzymes (EC 3.4.21.-) ; Ki-67 Antigen ; Interferon-gamma (82115-62-6)
    Language English
    Publishing date 2022-10-03
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural
    ZDB-ID 218698-6
    ISSN 1098-5522 ; 0019-9567
    ISSN (online) 1098-5522
    ISSN 0019-9567
    DOI 10.1128/iai.00259-22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: The relationship between synaptic density marker SV2A, glutamate and N-acetyl aspartate levels in healthy volunteers and schizophrenia: a multimodal PET and magnetic resonance spectroscopy brain imaging study.

    Onwordi, Ellis Chika / Whitehurst, Thomas / Mansur, Ayla / Statton, Ben / Berry, Alaine / Quinlan, Marina / O'Regan, Declan P / Rogdaki, Maria / Marques, Tiago Reis / Rabiner, Eugenii A / Gunn, Roger N / Vernon, Anthony C / Natesan, Sridhar / Howes, Oliver D

    Translational psychiatry

    2021  Volume 11, Issue 1, Page(s) 393

    Abstract: ... Additionally, it has been proposed that N-acetyl aspartate (NAA) levels reflect neuronal integrity. Here ... NAA in healthy volunteers (HV) and schizophrenia patients (SCZ). Forty volunteers (SCZ n = 18, HV n ...

    Abstract Glutamatergic excitotoxicity is hypothesised to underlie synaptic loss in schizophrenia pathogenesis, but it is unknown whether synaptic markers are related to glutamatergic function in vivo. Additionally, it has been proposed that N-acetyl aspartate (NAA) levels reflect neuronal integrity. Here, we investigated whether synaptic vesicle glycoprotein 2 A (SV2A) levels are related to glutamatergic markers and NAA in healthy volunteers (HV) and schizophrenia patients (SCZ). Forty volunteers (SCZ n = 18, HV n = 22) underwent [
    MeSH term(s) Aspartic Acid/analogs & derivatives ; Brain/diagnostic imaging ; Creatine ; Glutamic Acid ; Healthy Volunteers ; Humans ; Membrane Glycoproteins ; Nerve Tissue Proteins ; Neuroimaging ; Positron-Emission Tomography ; Proton Magnetic Resonance Spectroscopy ; Schizophrenia/diagnostic imaging
    Chemical Substances Membrane Glycoproteins ; Nerve Tissue Proteins ; SV2A protein, human (148845-93-6) ; Aspartic Acid (30KYC7MIAI) ; Glutamic Acid (3KX376GY7L) ; N-acetylaspartate (997-55-7) ; Creatine (MU72812GK0)
    Language English
    Publishing date 2021-07-17
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2609311-X
    ISSN 2158-3188 ; 2158-3188
    ISSN (online) 2158-3188
    ISSN 2158-3188
    DOI 10.1038/s41398-021-01515-3
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online: Robust Diamond/\b{eta}-Ga2O3 Hetero-p-n-junction Via Mechanically Integrating Their Building Blocks

    Rahaman, Imteaz / Ellis, Hunter D. / Fu, Kai

    2023  

    Abstract: We report a novel approach for crafting robust diamond/\b{eta}-Ga2O3 hetero-p-n-junctions ... temperatures. This effortlessly fabricated and remarkably resilient diamond/Ga2O3 hetero-p-n-junction pioneers ...

    Abstract We report a novel approach for crafting robust diamond/\b{eta}-Ga2O3 hetero-p-n-junctions through the mechanical integration of their bulk materials. This resulting heterojunction, with a turn-on voltage of ~2.7 V at room temperature, exhibits resilient electrical performance across a temperature spectrum up to 125{\deg}C, displaying minimal hysteresis-measuring as low as 0.2 V at room temperature and below 0.7 V at 125{\deg}C. Remarkably, the ideality factor achieves a record low value of 1.28, setting a new benchmark for diamond/ \b{eta}-Ga2O3 heterojunctions. The rectification ratio reaches over 10^8 at different temperatures. This effortlessly fabricated and remarkably resilient diamond/Ga2O3 hetero-p-n-junction pioneers a novel pathway for the exploration and fabrication of heterojunctions for ultra-wide bandgap semiconductors with substantial lattice mismatch and different thermal expansion coefficients.

    Comment: 13 pages, 4 figures, 1 table, journal and this draft has been submitted to 'Applied Physics Letters'
    Keywords Condensed Matter - Materials Science ; Physics - Applied Physics
    Subject code 669
    Publishing date 2023-11-27
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Transient T Cell Expansion, Activation, and Proliferation in Therapeutically Vaccinated Simian Immunodeficiency Virus-Positive Macaques Treated with N-803.

    Harwood, Olivia E / Balgeman, Alexis J / Weaver, Abigail J / Ellis-Connell, Amy L / Weiler, Andrea M / Erickson, Katrina N / Matschke, Lea M / Golfinos, Athena E / Vezys, Vaiva / Skinner, Pamela J / Safrit, Jeffrey T / Edlefsen, Paul T / Reynolds, Matthew R / Friedrich, Thomas C / O'Connor, Shelby L

    Journal of virology

    2022  Volume 96, Issue 23, Page(s) e0142422

    Abstract: Vaccine strategies aimed at eliciting human immunodeficiency virus (HIV)-specific ... ...

    Abstract Vaccine strategies aimed at eliciting human immunodeficiency virus (HIV)-specific CD8
    MeSH term(s) Animals ; CD8-Positive T-Lymphocytes ; Cell Proliferation ; Macaca mulatta/immunology ; SAIDS Vaccines ; Simian Acquired Immunodeficiency Syndrome/immunology ; Simian Immunodeficiency Virus ; Vaccination ; Vaccinia virus
    Chemical Substances ALT-803 ; SAIDS Vaccines
    Language English
    Publishing date 2022-11-15
    Publishing country United States
    Document type Journal Article ; Research Support, N.I.H., Extramural
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.01424-22
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Mathematical modeling of N-803 treatment in SIV-infected non-human primates.

    Jonathan W Cody / Amy L Ellis-Connell / Shelby L O'Connor / Elsje Pienaar

    PLoS Computational Biology, Vol 17, Iss 7, p e

    2021  Volume 1009204

    Abstract: ... In one study, an IL-15 superagonist, N-803, suppressed Simian Immunodeficiency Virus (SIV) in non-human ... with continued N-803 treatment, partially returning after long treatment interruption. While there is evidence ... of these mechanisms to the observed viral dynamics have not been quantified. Here, we utilize mathematical models of N ...

    Abstract Immunomodulatory drugs could contribute to a functional cure for Human Immunodeficiency Virus (HIV). Interleukin-15 (IL-15) promotes expansion and activation of CD8+ T cell and natural killer (NK) cell populations. In one study, an IL-15 superagonist, N-803, suppressed Simian Immunodeficiency Virus (SIV) in non-human primates (NHPs) who had received prior SIV vaccination. However, viral suppression attenuated with continued N-803 treatment, partially returning after long treatment interruption. While there is evidence of concurrent drug tolerance, immune regulation, and viral escape, the relative contributions of these mechanisms to the observed viral dynamics have not been quantified. Here, we utilize mathematical models of N-803 treatment in SIV-infected macaques to estimate contributions of these three key mechanisms to treatment outcomes: 1) drug tolerance, 2) immune regulation, and 3) viral escape. We calibrated our model to viral and lymphocyte responses from the above-mentioned NHP study. Our models track CD8+ T cell and NK cell populations with N-803-dependent proliferation and activation, as well as viral dynamics in response to these immune cell populations. We compared mathematical models with different combinations of the three key mechanisms based on Akaike Information Criterion and important qualitative features of the NHP data. Two minimal models were capable of reproducing the observed SIV response to N-803. In both models, immune regulation strongly reduced cytotoxic cell activation to enable viral rebound. Either long-term drug tolerance or viral escape (or some combination thereof) could account for changes to viral dynamics across long breaks in N-803 treatment. Theoretical explorations with the models showed that less-frequent N-803 dosing and concurrent immune regulation blockade (e.g. PD-L1 inhibition) may improve N-803 efficacy. However, N-803 may need to be combined with other immune therapies to countermand viral escape from the CD8+ T cell response. Our mechanistic model will inform ...
    Keywords Biology (General) ; QH301-705.5
    Subject code 570
    Language English
    Publishing date 2021-07-01T00:00:00Z
    Publisher Public Library of Science (PLoS)
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Anti-N-methyl-D-aspartate receptor encephalitis: An observational and comparative study in Mexican children and adults.

    Herrera-Mora, Patricia / Munive-Baez, Leticia / Ruiz García, Matilde / Galindo-Martínez, Alfredo / Maldonado-Diaz, Daniela Ellis / Delgado, Rosa Delia / Cárdenas, Graciela

    Clinical neurology and neurosurgery

    2021  Volume 210, Page(s) 106986

    Abstract: Objective: To present a case series of encephalitis patients with anti-N-methyl-D-aspartate ...

    Abstract Objective: To present a case series of encephalitis patients with anti-N-methyl-D-aspartate receptor antibodies, attending two neurological referral centers in a three-year period.
    Methods: A retrospective, descriptive, comparative study included child and adult patients in two neurological populations, positive for antibodies against the NR1 and NR2 subunits of the glutamate (NMDA) receptor in serum and CSF, as determined during a three-year period.
    Results: Sixty-six patients were included (40 children and 26 adults). Male patients were more affected (M: F ratio was 1:0.6). No differences in progression or hospitalization time were observed between groups. In children, 35% of patients showed herpetic infection before autoimmune encephalitis (P = 0.01). Among viral prodromal symptoms, upper respiratory tract infection (P = 0.02) and fever (P = 0.001) predominated in children, while infectious gastroenteritis was more frequent in adults (P = 0.03). Among neuropsychiatric signs, mental confusion (P = 0.0001) and orofacial dyskinesia/oromandibular dystonia (P = 0.0001) were frequent in children, while emotional lability (P = 0.03), catatonia (P = 0.0001), and headache (P = 0.005) predominated in adults. The score in the modified Rankin scale on admission was higher in children (4.3 ± 0.8 vs. 2.2 ± 1.3, P = 0.0001), but at one-year of clinical follow up no significant differences were found.
    Conclusions: Male patients were predominantly affected in our population. One-third of all patients developed prodromal infection. Neuropsychiatric clinical complaints were different in children and adults. However, post-hospitalization recovery was similar between groups.
    MeSH term(s) Adolescent ; Adult ; Age Factors ; Anti-N-Methyl-D-Aspartate Receptor Encephalitis/cerebrospinal fluid ; Anti-N-Methyl-D-Aspartate Receptor Encephalitis/diagnostic imaging ; Anti-N-Methyl-D-Aspartate Receptor Encephalitis/epidemiology ; Child ; Child, Preschool ; Electroencephalography/methods ; Female ; Follow-Up Studies ; HEK293 Cells ; Humans ; Male ; Mexico/epidemiology ; Prodromal Symptoms ; Sex Factors ; Young Adult
    Language English
    Publishing date 2021-10-11
    Publishing country Netherlands
    Document type Comparative Study ; Journal Article ; Multicenter Study ; Observational Study
    ZDB-ID 193107-6
    ISSN 1872-6968 ; 0303-8467
    ISSN (online) 1872-6968
    ISSN 0303-8467
    DOI 10.1016/j.clineuro.2021.106986
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Structural insights into the multinuclear speciation of tetravalent cerium in the tri-n-butyl phosphate-n-dodecane solvent extraction system.

    Antonio, Mark R / Ellis, Ross J / Estes, Shanna L / Bera, Mrinal K

    Physical chemistry chemical physics : PCCP

    2017  Volume 19, Issue 32, Page(s) 21304–21316

    Abstract: ... cerium, Ce(iv), from aqueous nitric acid (3 M) with tri-n-butyl phosphate (TBP) in n-dodecane reveal ...

    Abstract X-ray and electrochemical studies of organic phases obtained by the extraction of tetravalent cerium, Ce(iv), from aqueous nitric acid (3 M) with tri-n-butyl phosphate (TBP) in n-dodecane reveal a tetranuclear Ce(iv) structural motif. This finding is consistent with the results of previous liquid-liquid extraction (LLE) studies that implicate the aggregation of (Ce-O-Ce)
    Language English
    Publishing date 2017-08-16
    Publishing country England
    Document type Journal Article
    ZDB-ID 1476244-4
    ISSN 1463-9084 ; 1463-9076
    ISSN (online) 1463-9084
    ISSN 1463-9076
    DOI 10.1039/c7cp03350h
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article: Analysis of Hendra Virus Fusion Protein N-Terminal Transmembrane Residues

    Barrett, Chelsea T. / Neal, Hadley E. / Edmonds, Kearstin / Zamora, J. Lizbeth Reyes / Moncman, Carole L. / Popa, Andreea / Smith, Everett Clinton / Webb, Stacy R. / Dutch, Rebecca Ellis

    Viruses. 2021 Nov. 24, v. 13, no. 12

    2021  

    Abstract: ... mutagenesis to explore the residues in the N-terminus of this region (residues 487–506). In addition ...

    Abstract Hendra virus (HeV) is a zoonotic enveloped member of the family Paramyoxviridae. To successfully infect a host cell, HeV utilizes two surface glycoproteins: the attachment (G) protein to bind, and the trimeric fusion (F) protein to merge the viral envelope with the membrane of the host cell. The transmembrane (TM) region of HeV F has been shown to have roles in F protein stability and the overall trimeric association of F. Previously, alanine scanning mutagenesis has been performed on the C-terminal end of the protein, revealing the importance of β-branched residues in this region. Additionally, residues S490 and Y498 have been demonstrated to be important for F protein endocytosis, needed for the proteolytic processing of F required for fusion. To complete the analysis of the HeV F TM, we performed alanine scanning mutagenesis to explore the residues in the N-terminus of this region (residues 487–506). In addition to confirming the critical roles for S490 and Y498, we demonstrate that mutations at residues M491 and L492 alter F protein function, suggesting a role for these residues in the fusion process.
    Keywords Hendra henipavirus ; alanine ; endocytosis ; glycoproteins ; mutagenesis ; proteolysis ; viral fusion proteins
    Language English
    Dates of publication 2021-1124
    Publishing place Multidisciplinary Digital Publishing Institute
    Document type Article
    ZDB-ID 2516098-9
    ISSN 1999-4915
    ISSN 1999-4915
    DOI 10.3390/v13122353
    Database NAL-Catalogue (AGRICOLA)

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