106 research outputs found
Die chemotaktische Antwort neutrophiler Granulozyten ist genetisch determiniert
Das 825T-Allel des C825T-Polymorphismus im Gen GNB3, welches fĂŒr die b-Untereinheit heterotrimerer G-Proteine kodiert, ist mit der Expression der kurzen SpleiĂvariante Gb3-s und verstĂ€rkter Signaltransduktion via Pertussistoxin-sensitiver G-Proteine assoziiert. Da der bg-Untereinheit der G-Proteine eine entscheidende Rolle bei der gerichteten Zellbewegung (Chemotaxis) zukommt, stellte sich die Frage, ob strukturell unterschiedliche G-Proteine, nĂ€mlich G-Proteine mit der b-Untereinheit Gb3 und G-Proteine mit der SpleiĂvariante Gb3-s, unterschiedlich starke chemotaktische Antworten von menschlichen neutrophilen Granulozyten hervorrufen. Menschliche neutrophile Granulozyten bewegen sich gezielt auf EntzĂŒndungsherde zu und produzieren zur BekĂ€mpfung von inflammatorischen Noxen Sauerstoffradikale.
In dieser Arbeit wurden in AbhÀngigkeit vom Genotyp am GNB3-Locus (CC-, TC- oder TT-Genotyp) Chemotaxis, intrazellulÀrer Kalziumanstieg und Superoxid-Generation von menschlichen neutrophilen Granulozyten betrachtet, jeweils nach Stimulation mit den chemotaktisch wirksamen Substanzen N-formyl-methionyl-leucyl-phenylalanin (fMLP) und Interleukin-8 (IL-8).
Bei Stimulation mit fMLP wurde eine signifikant gesteigerte Zellmigration bei Neutrophilen von Individuen mit dem TC/TT-Genotyp (EC50 = 1.5 ± 1.3 nM) verglichen mit Neutrophilen von homozygoten C-AlleltrĂ€gern (EC50 = 5.9 ± 1.5 nM) bei Konzentrationen zwischen 0.1 und 100 nM gefunden. Stimulationen mit IL-8-Konzentrationen zwischen 0.1 und 10 nM zeigten eine bis zu 2.5-fach höhere Chemotaxis der Granulozyten von 825T-AlleltrĂ€gern im Vergleich zu den homozygoten C-AlleltrĂ€gern. Im Gegensatz zu diesen Ergebnissen erwiesen sich intrazellulĂ€rer Anstieg der Kalziumkonzentration nach Stimulation mit IL-8 und Freisetzung von Sauerstoffradikalen als unabhĂ€ngig vom Genotyp. Stimulation mit fMLP bewirkte bei T-AlleltrĂ€gern im Vergleich zu den homozygoten C-AlleltrĂ€gern eine signifikant kleinere Erhöhung der intrazellulĂ€ren Kalziumkonzentration. Dies zeigt, daĂ zellulĂ€re Reaktionen, bei denen Gb3-s beteiligt ist, nicht zwangslĂ€ufig erhöht sein mĂŒssen.
Unter der Annahme, daĂ eine verstĂ€rkte Chemotaxis der Neutrophilen von 825T-AlleltrĂ€gern gegenĂŒber solchen von homozygoten C825-AlleltrĂ€gern eine bessere zellulĂ€re Immunkompetenz bedeutet, könnte die Genotypisierung eine wertvolle diagnostische und prognostische Hilfe zur EinschĂ€tzung der individuellen Immunkompetenz darstellen
Targeting NKG2D ligands in glioblastoma with a bispecific T-cell engager is augmented with conventional therapy and enhances oncolytic virotherapy of glioma stem-like cells
Background: Glioblastoma (GBM) almost invariably becomes resistant towards conventional treatment of radiotherapy and temozolomide (TMZ) chemotherapy, partly due to subpopulations of intrinsically resistant glioma stem-like cells (GSC). The oncolytic herpes simplex virus-1 G207 is a promising approach for GBM virotherapy although its efficacy in patients with GBM is often limited. Natural killer group 2 member D ligands (NKG2DLs) are minimally expressed by healthy cells but are upregulated by the DNA damage response (DDR) and in malignant cells with chronic DDR signaling, resulting in innate immune activation. Methods: We have designed a bispecific T-cell engager (BiTE) capable of cross-linking CD3 on T cells with NKG2DL-expressing GBM cells. We then engineered the G207 virus to express the NKG2D BiTE and secrete it from infected cells. The efficacy of the free BiTE and BiTE delivered by G207 was evaluated in combination with conventional therapies in GBM cells and against patient-derived GSCs in the context of T-cell activation and target cell viability. Results: NKG2D BiTE-mediated cross-linking of GBM cells and T cells causes antigen-independent T-cell activation, pro-inflammatory cytokine release, and tumor cell death, thereby combining direct viral oncolysis with BiTE-mediated cytotoxicity. Surface NKG2DL expression was further elevated on GBM cells following pretreatment with sublethal doses of TMZ and radiation to induce the DDR, increasing sensitivity towards G207-NKG2D BiTE and achieving synergistic cytotoxicity. We also demonstrate a novel strategy for targeting GSCs that are non-permissive to G207 infection but remain sensitive to NKG2D BiTE. Conclusions: We propose a potential model for targeting GSCs in heterogeneous tumors, whereby differentiated GBM cells infected with G207-NKG2D BiTE produce NKG2D BiTE locally, directing T-cell cytotoxicity towards the GSC subpopulations in the tumor microenvironment
An Inducible Expression System of the Calcium-Activated Potassium Channel 4 to Study the Differential Impact on Embryonic Stem Cells
Rationale. The family of calcium-activated potassium channels consists of four members with varying biological functions and conductances. Besides membrane potential modulation, SK channels have been found to be involved in cardiac pacemaker cell development from ES cells and morphological shaping of neural stem cells. Objective. Distinct SK channel subtype expression in ES cells might elucidate their precise impact during cardiac development. We chose SK channel subtype 4 as a potential candidate influencing embryonic stem cell differentiation. Methods. We generated a doxycycline inducible mouse ES cell line via targeted homologous recombination of a cassette expressing a bicistronic construct encoding SK4 and a fluorophore from the murine HPRT locus. Conclusion. We characterized the mouse ES cell line iSK4-AcGFP. The cassette is readily expressed under the control of doxycycline, and the overexpression of SK4 led to an increase in cardiac and pacemaker cell differentiation thereby serving as a unique tool to characterize the cell biological variances due to specific SK channel overexpression
Highly variable upper and abyssal overturning cells in the South Atlantic
The Meridional Overturning Circulation (MOC) is a primary mechanism driving oceanic heat redistribution on Earth, thereby affecting Earthâs climate and weather. However, the full-depth structure and variability of the MOC are still poorly understood, particularly in the South Atlantic. This study presents unique multiyear records of the oceanic volume transport of both the upper (~3100 meters) overturning cells based on daily moored measurements in the South Atlantic at 34.5°S. The vertical structure of the time-mean flows is consistent with the limited historical observations. Both the upper and abyssal cells exhibit a high degree of variability relative to the temporal means at time scales, ranging from a few days to a few weeks. Observed variations in the abyssal flow appear to be largely independent of the flow in the overlying upper cell. No meaningful trends are detected in either cell.Fil: KersalĂ©, Marion. National Ocean And Atmospheric Administration; Estados Unidos. University of Miami; Estados UnidosFil: Meinen, Christopher S.. National Ocean And Atmospheric Administration; Estados UnidosFil: Perez, Renellys C.. National Ocean And Atmospheric Administration; Estados UnidosFil: Le HĂ©naff, Matthieu. National Ocean And Atmospheric Administration; Estados Unidos. University of Miami; Estados UnidosFil: Valla, Daniel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Ministerio de Defensa. Armada Argentina. Servicio de HidrografĂa Naval. Departamento OceanografĂa; ArgentinaFil: Lamont, Tarron. University of Cape Town; SudĂĄfricaFil: Sato, Olga T.. Universidade de Sao Paulo; BrasilFil: Dong, Shenfu. National Ocean And Atmospheric Administration; Estados UnidosFil: Terre, T.. University of Brest; Francia. Centre National de la Recherche Scientifique; FranciaFil: van Caspel, M.. Universidade de Sao Paulo; BrasilFil: Chidichimo, MarĂa Paz. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Ministerio de Defensa. Armada Argentina. Servicio de HidrografĂa Naval. Departamento OceanografĂa; ArgentinaFil: van den Berg, Marcel Alexander. Department of Environmental Affairs; SudĂĄfricaFil: Speich, Sabrina. University Of Cape Town; SudĂĄfricaFil: Piola, Alberto Ricardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentina. Ecole Normale Superieure. Laboratoire de Meteorologie Dynamique; Francia. Ministerio de Defensa. Armada Argentina. Servicio de HidrografĂa Naval. Departamento OceanografĂa; Argentina. Instituto Franco-Argentino sobre Estudios del Clima y sus Impactos; Argentina. Universidad de Buenos Aires; ArgentinaFil: Campos, Edmo. Universidade de Sao Paulo; Brasil. American University Of Sharjah.; Emiratos Ărabes UnidosFil: Ansorge, Isabelle. University of Cape Town; SudĂĄfricaFil: Volkov, Denis L.. University of Miami; Estados Unidos. National Ocean And Atmospheric Administration; Estados UnidosFil: Lumpkin, Rick. National Ocean And Atmospheric Administration; Estados UnidosFil: Garzoli, S. L.. University of Miami; Estados Unidos. National Ocean And Atmospheric Administration; Estados Unido
Improvements to services at the European Nucleotide Archive
The European Nucleotide Archive (ENA; http://www.ebi.ac.uk/ena) is Europeâs primary nucleotide sequence archival resource, safeguarding open nucleotide data access, engaging in worldwide collaborative data exchange and integrating with the scientific publication process. ENA has made significant contributions to the collaborative nucleotide archival arena as an active proponent of extending the traditional collaboration to cover capillary and next-generation sequencing information. We have continued to co-develop data and metadata representation formats with our collaborators for both data exchange and public data dissemination. In addition to the DDBJ/EMBL/GenBank feature table format, we share metadata formats for capillary and next-generation sequencing traces and are using and contributing to the NCBI SRA Toolkit for the long-term storage of the next-generation sequence traces. During the course of 2009, ENA has significantly improved sequence submission, search and access functionalities provided at EMBLâEBI. In this article, we briefly describe the content and scope of our archive and introduce major improvements to our services
TOI-1338 : TESS' first transiting circumbinary planet
Funding: Funding for the DPAC has been provided by national institutions, in particular, the institutions participating in the Gaia Multilateral Agreement. W.F.W. and J.A.O.thank John Hood Jr. for his generous support of exoplanet research at SDSU. Support was also provided and acknowledged through NASA Habitable Worlds grant 80NSSC17K0741 and NASA XRP grant 80NSSC18K0519. This work is partly supported by NASA Habitable Worlds grant 80NSSC17K0741. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship Program under grant No.(DGE-1746045). A.H.M.J.T. has received funding from the European Research Council (ERC) under the European Unionâs Horizon 2020 research and innovation programme (grant agreement No. 803193/BEBOP) and from a Leverhulme Trust Research Project grant No. RPG-2018-418. A.C. acknowledges support by CFisUC strategic project (UID/FIS/04564/2019).We report the detection of the first circumbinary planet (CBP) found by Transiting Exoplanet Survey Satellite (TESS). The target, a known eclipsing binary, was observed in sectors 1 through 12 at 30 minute cadence and in sectors 4 through 12 at 2 minute cadence. It consists of two stars with masses of 1.1 Mâ and 0.3 Mâ on a slightly eccentric (0.16), 14.6 day orbit, producing prominent primary eclipses and shallow secondary eclipses. The planet has a radius of âŒ6.9 Râ and was observed to make three transits across the primary star of roughly equal depths (âŒ0.2%) but different durationsâa common signature of transiting CBPs. Its orbit is nearly circular (e â 0.09) with an orbital period of 95.2 days. The orbital planes of the binary and the planet are aligned to within âŒ1°. To obtain a complete solution for the system, we combined the TESS photometry with existing ground-based radial-velocity observations in a numerical photometric-dynamical model. The system demonstrates the discovery potential of TESS for CBPs and provides further understanding of the formation and evolution of planets orbiting close binary stars.Publisher PDFPeer reviewe
Expression of <i>Idh1</i><sup>R132H</sup> in the murine subventricular zone stem cell niche recapitulates features of early gliomagenesis
Isocitrate dehydrogenase 1 mutations drive human gliomagenesis, probably through neomorphic enzyme activity that produces D-2-hydroxyglutarate. To model this disease, we conditionally expressed Idh1(R132H) in the subventricular zone (SVZ) of the adult mouse brain. The mice developed hydrocephalus and grossly dilated lateral ventricles, with accumulation of 2-hydroxyglutarate and reduced α-ketoglutarate. Stem and transit amplifying/progenitor cell populations were expanded, and proliferation increased. Cells expressing SVZ markers infiltrated surrounding brain regions. SVZ cells also gave rise to proliferative subventricular nodules. DNA methylation was globally increased, while hydroxymethylation was decreased. Mutant SVZ cells overexpressed Wnt, cell-cycle and stem cell genes, and shared an expression signature with human gliomas. Idh1(R132H) mutation in the major adult neurogenic stem cell niche causes a phenotype resembling gliomagenesis
In-frame seven amino-acid duplication in AIP arose over the last 3000 years, disrupts protein interaction and stability and is associated with gigantism.
Mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are associated with pituitary adenoma, acromegaly and gigantism. Identical alleles in unrelated pedigrees could be inherited from a common ancestor or result from recurrent mutation events.EDGE Project ID: 172
Marine mammals exploring the oceans pole to pole
Polar oceans are poorly monitored despite the important role they play in
regulating Earthâs climate system. Marine mammals equipped with biologging devices
are now being used to fill the data gaps in these logistically difficult to sample regions.
Since 2002, instrumented animals have been generating exceptionally large data sets
of oceanographic CTD casts (>500,000 profiles), which are now freely available to
the scientific community through the MEOP data portal (http://meop.net). MEOP
(Marine Mammals Exploring the Oceans Pole to Pole) is a consortium of international
researchers dedicated to sharing animal-derived data and knowledge about the polar
oceans. Collectively, MEOP demonstrates the power and cost-effectiveness of using
marine mammals as data-collection platforms that can dramatically improve the ocean
observing system for biological and physical oceanographers. Here, we review the
MEOP program and database to bring it to the attention of the international community.http://www.tos.org/oceanographyam2017Mammal Research InstituteZoology and Entomolog
Genome sequencing analysis identifies new loci associated with Lewy body dementia and provides insights into its genetic architecture
The genetic basis of Lewy body dementia (LBD) is not well understood. Here, we performed whole-genome sequencing in large cohorts of LBD cases and neurologically healthy controls to study the genetic architecture of this understudied form of dementia, and to generate a resource for the scientific community. Genome-wide association analysis identified five independent risk loci, whereas genome-wide gene-aggregation tests implicated mutations in the gene GBA. Genetic risk scores demonstrate that LBD shares risk profiles and pathways with Alzheimer's disease and Parkinson's disease, providing a deeper molecular understanding of the complex genetic architecture of this age-related neurodegenerative condition
- âŠ