TY - JOUR A1 - Volceanov, Larisa A1 - Herbst, Katharina A1 - Biniossek, Martin A1 - Schilling, Oliver A1 - Haller, Dirk A1 - Nölke, Thilo A1 - Subbarayal, Prema A1 - Rudel, Thomas A1 - Zieger, Barbara A1 - Häcker, Georg T1 - Septins Arrange F-Actin-Containing Fibers on the Chlamydia trachomatis Inclusion and Are Required for Normal Release of the Inclusion by Extrusion JF - MBIO N2 - Chlamydia trachomatis is an obligate intracellular human pathogen that grows inside a membranous, cytosolic vacuole termed an inclusion. Septins are a group of 13 GTP-binding proteins that assemble into oligomeric complexes and that can form higher-order filaments. We report here that the septins SEPT2, -9, -11, and probably -7 form fibrillar structures around the chlamydial inclusion. Colocalization studies suggest that these septins combine with F actin into fibers that encase the inclusion. Targeting the expression of individual septins by RNA interference (RNAi) prevented the formation of septin fibers as well as the recruitment of actin to the inclusion. At the end of the developmental cycle of C. trachomatis, newly formed, infectious elementary bodies are released, and this release occurs at least in part through the organized extrusion of intact inclusions. RNAi against SEPT9 or against the combination of SEPT2/7/9 substantially reduced the number of extrusions from a culture of infected HeLa cells. The data suggest that a higher-order structure of four septins is involved in the recruitment or stabilization of the actin coat around the chlamydial inclusion and that this actin recruitment by septins is instrumental for the coordinated egress of C. trachomatis from human cells. The organization of F actin around parasite-containing vacuoles may be a broader response mechanism of mammalian cells to the infection by intracellular, vacuole-dwelling pathogens. IMPORTANCE Chlamydia trachomatis is a frequent bacterial pathogen throughout the world, causing mostly eye and genital infections. C. trachomatis can develop only inside host cells; it multiplies inside a membranous vacuole in the cytosol, termed an inclusion. The inclusion is covered by cytoskeletal "coats" or "cages," whose organization and function are poorly understood. We here report that a relatively little-characterized group of proteins, septins, is required to organize actin fibers on the inclusion and probably through actin the release of the inclusion. Septins are a group of GTP-binding proteins that can organize into heteromeric complexes and then into large filaments. Septins have previously been found to be involved in the interaction of the cell with bacteria in the cytosol. Our observation that they also organize a reaction to bacteria living in vacuoles suggests that they have a function in the recognition of foreign compartments by a parasitized human cell. KW - mammalian septins KW - host-cells KW - binding KW - proteins KW - organization KW - cytoskeleton KW - cytokinesis KW - mechanisms KW - expression KW - protease Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115421 SN - 2150-7511 VL - 5 IS - 5 ER - TY - THES A1 - Herbst, Thomas T1 - Funktionalisierung organischer Verbindungen durch Borylentransfer T1 - Functionalization of organic substrates by borylene transfer N2 - Im Rahmen dieser Arbeit wurden Gruppe 6 Aminoborylenkomplexe zum Borylentransfer auf Alkine verwendet. Die Bor–Übergangsmetallmehrfachbindung wird gespalten, und die Boryleneinheit (BR) auf die C-C-Dreifachbindung übertragen. Diese formale [2+1]-Cycloaddition macht Borirene (Boracyclopropene) in sehr guten Ausbeuten zugänglich. In früheren Arbeiten ist die Borirensynthese entweder auf geringe Ausbeuten oder auf wenige Beispiele mit schwer zugänglichen Edukten beschränkt. Die entwickelte Methode des Borylentranfers, macht die nach Hückel kleinsten, aromatischen Systeme im Sinne einer „Eintopfreaktion“ darstellbar. Die Verbindungen konnten vollständig spektroskopisch und strukturell charakterisiert werden. Die photophysikalischen Eigenschaften der Borirene wurden mit UV/Vis-Spektroskopie untersucht, mit dem Ergebnis, dass diese im nicht sichtbaren Bereich des Spektrums absorbieren.Die allgemeine Anwendbarkeit des Borylentransfers konnte durch eine doppelte Borylenübertragung auf Diine belegt werden. Es konnte gezeigt werden, dass zwei Aminoboryleneinheiten stöchiometrisch auf ein Substrat übertragen werden. Auf diese Weise konnten erstmalig Bisborirene spektroskopisch und strukturell charakterisiert werden. Die Röntgenstrukturanalysen der Bisborirene 82 und 86 haben ergeben, dass aufgrund der sperrigen Bis(trimethylsilyl)aminosubstituenten eine starke Verdrillung der beiden Boracyclopropeneinheiten zueinander vorliegt. Im Falle von 82 sind beide Ebenen der dreigliedrigen Ringsysteme nahezu senkrecht zueinander angeordnet. Die in guten Ausbeuten synthetisierten Borirene konnten wiederum für deren Reaktivitätsuntersuchungen eingesetzt werden. Interessanterweise war es möglich, das Boriren 58e zu hydroborieren. In Gegenwart von 9-BBN erfolgte eine selektive B–C-Bindungsspaltung von 58e, unter Bildung einer B–H-Bindung. Ein weiterer Aspekt dieser Arbeit sind die Reaktivitätsstudien der Borylenkomplexe 32 und 33, gegenüber C=O-Doppelbindungen sowie C–N-Mehrfachbindungen. Es wurden durch die photochemischen Umsetzungen von 32 bzw. 33 mit Aceton, Benzophenon und tert-Butylcyanid, andere borhaltige Verbindungen erhalten, deren Konstitution aber nicht geklärt werden konnte. Die Reaktivitätsuntersuchungen von 32 und 33 gegenüber Alkenen, hat ergeben, dass eine formale Insertion des Borylenliganden in eine olefinische C–H-Bindung stattfindet. C–H-Aktivierungen durch Borylene wurden vorher nur in der Matrix beobachtet oder postuliert, ohne die erhaltenen Reaktionsprodukte zu charakterisieren. Durch die photochemische Umsetzung von 32 mit 3,3-Dimethyl-1-buten sind die Verbindungen 104 und 105 zugänglich (Abb. 78). Das Vinylaminoboran 104 wurde als farblose Flüssigkeit in 31% Ausbeute erhalten, und das Tieftemperatur 1H-NMR-Spektrum zeigte deutlich ein Signal des borgebundenen H-Atoms bei = 5.47ppm. Die Struktur des Olefinkomplexes 105 konnte durch Röntgenstrukturanalyse geklärt werden und in Übereinstimmung mit der NMR-Spektroskopie, lassen sich die Bindungsverhältnisse der B–H-Bindung als sigma-Koordination zum Chromzentrum erklären. N2 - In this thesis group 6 aminoborylene complexes were used as borylene sources in presence of main group element multiple bond systems. The reactivity of the complexes 32 and 33 with several alkynes was studied extensively. In Fig. 79 the formal [2+1]-cycloaddition is outlined, the transition metal–boron multiple bond is cleaved, and the borylene moiety (BR) transferred to the C-C-triple bond. The borylene transfer allows access to borirenes (boracyclopropenes) by a high yielding, straightforward route (Fig. 80). Earlier reported preparations of borirenes were low yielding or restricted in scope. The obtained compounds, which are aromatic and isoelectronic to the cyclopropenylium cation, were completely spectroscopically characterized and a few of their structures could be determined by X-Ray diffraction. Their photophysical properties were investigated by UV/Vis absorption, and their maximum absorption was found in the non- visible region. The versatility of the synthetic method was proved by borylene transfer to diynes, ultimately resulting in two aminoborylene moieties being transferred stochiometrically to one substrate (Fig. 81). The bisborirenes were obtained in good yields and were completely spectroscopically characterised and their structures were determined by X-Ray structure analysis. The X-Ray structure of 82 (Fig. 81) and 86 (Fig. 82) showed that the two boracyclopropene units were strongly non-co-planar. In case of 82 the planes of the three-membered rings were nearly perpendicular to each other. The borirenes were also used for reactivity studies. Interestingly it was possible to hydroborate the borirene 58e (Fig. 83). In presence of 9-BBN one B–C bond is cleaved from 58e, with the formation of a B–H bond. Further reactivity studies of the aminoborylene complexes 32 and 33 were made with C=O double bonds and C–N multiple bonds. By photochemical activation of 32 and 33 with acetone, benzophenone and tbutylcyanide, other boron containing compounds were obtained, but their constitution could not be determined. In contrast to the addition of the borylene moiety to alkynes, the investigation of the reactivity profile of 32 with olefins uncovered a formal insertion of the borylene ligand into the vinylic C–H bond. C–H activations by borylenes have been previously observed in a matrix or postulated without the characterization of the reaction products. The irradiation of 32 with 3,3-dimethyl-1-butene led to the compounds 104 and 105 (Fig. 85). The vinylaminoborane 104 was isolated as a colorless liquid in 31% yield, and its low temperature 1H-NMR-spectra showed clearly the boron bound proton at 5.47ppm. The structure of the olefin complex 105 was determined by X-Ray diffraction and is in agreement with the NMR-spectroscopical examination, the B–H bond is sigma-coordinated to the chromium center resulting in a three-center-two-electron bonding situation. KW - Bor KW - Borylene KW - Borirene KW - Cycloadditionen KW - Insertionsreaktionen KW - Borylentransfer KW - Boracyclopropene KW - Vinylaminoborane KW - Boron KW - borylenes KW - borirenes KW - cycloadditions KW - borylene transfer Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-36046 ER - TY - JOUR A1 - Rinaldetti, Sébastien A1 - Pfirrmann, Markus A1 - Manz, Kirsi A1 - Guilhot, Joelle A1 - Dietz, Christian A1 - Panagiotidis, Panayiotidis A1 - Spiess, Birgit A1 - Seifarth, Wolfgang A1 - Fabarius, Alice A1 - Müller, Martin A1 - Pagoni, Maria A1 - Dimou, Maria A1 - Dengler, Jolanta A1 - Waller, Cornelius F. A1 - Brümmendorf, Tim H. A1 - Herbst, Regina A1 - Burchert, Andreas A1 - Janßen, Carsten A1 - Goebeler, Maria Elisabeth A1 - Jost, Philipp J. A1 - Hanzel, Stefan A1 - Schafhausen, Philippe A1 - Prange-Krex, Gabriele A1 - Illmer, Thomas A1 - Janzen, Viktor A1 - Klausmann, Martine A1 - Eckert, Robert A1 - Büschel, Gerd A1 - Kiani, Alexander A1 - Hofmann, Wolf-Karsten A1 - Mahon, François-Xavier A1 - Saussele, Susanne T1 - Effect of ABCG2, OCT1, and ABCB1 (MDR1) Gene Expression on Treatment-Free Remission in a EURO-SKI Subtrial JF - Clinical Lymphoma, Myeloma & Leukemia N2 - Within the EURO-SKI trial, 132 chronic phase CML patients discontinued imatinib treatment. RNA was isolated from peripheral blood in order to analyze the expression of MDR1, ABCG2 and OCT1. ABCG2 was predictive for treatment-free remission in Cox regression analysis. High transcript levels of the ABCG2 efflux transporter (>4.5 parts per thousand) were associated with a twofold higher risk of relapse. Introduction: Tyrosine kinase inhibitors (TKIs) can safely be discontinued in chronic myeloid leukemia (CML) patients with sustained deep molecular response. ABCG2 (breast cancer resistance protein), OCT1 (organic cation transporter 1), and ABCB1 (multidrug resistance protein 1) gene products are known to play a crucial role in acquired pharmacogenetic TKI resistance. Their influence on treatment-free remission (TFR) has not yet been investigated. Materials and Methods: RNA was isolated on the last day of TKI intake from peripheral blood leukocytes of 132 chronic phase CML patients who discontinued TKI treatment within the European Stop Tyrosine Kinase Inhibitor Study trial. Plasmid standards were designed including subgenic inserts of OCT1, ABCG2, and ABCB1 together with GUSB as reference gene. For expression analyses, quantitative real-time polymerase chain reaction was used. Multiple Cox regression analysis was performed. In addition, gene expression cutoffs for patient risk stratification were investigated. Results: The TFR rate of 132 patients, 12 months after TKI discontinuation, was 54% (95% confidence interval [CI], 46%-62%). ABCG2 expression (parts per thousand) was retained as the only significant variable (P=.02; hazard ratio, 1.04; 95% CI, 1.01-1.07) in multiple Cox regression analysis. Only for the ABCG2 efflux transporter, a significant cutoff was found (P=.04). Patients with an ABCG2/GUSB transcript level >4.5 parts per thousand (n=93) showed a 12-month TFR rate of 47% (95% CI, 37%-57%), whereas patients with low ABCG2 expression (<= 4.5 parts per thousand; n=39) had a 12-month TFR rate of 72% (95% CI, 55%-82%). Conclusion: In this study, we investigated the effect of pharmacogenetics in the context of a CML treatment discontinuation trial. The transcript levels of the efflux transporter ABCG2 predicted TFR after TKI discontinuation. (C) 2018 The Authors. Published by Elsevier Inc. KW - ABCG2 KW - Biomarker KW - CML KW - Imatinib KW - Prediction Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-226281 VL - 18 IS - 4 ER - TY - JOUR A1 - Haeusner, Sebastian A1 - Herbst, Laura A1 - Bittorf, Patrick A1 - Schwarz, Thomas A1 - Henze, Chris A1 - Mauermann, Marc A1 - Ochs, Jelena A1 - Schmitt, Robert A1 - Blache, Ulrich A1 - Wixmerten, Anke A1 - Miot, Sylvie A1 - Martin, Ivan A1 - Pullig, Oliver T1 - From Single Batch to Mass Production–Automated Platform Design Concept for a Phase II Clinical Trial Tissue Engineered Cartilage Product JF - Frontiers in Medicine N2 - Advanced Therapy Medicinal Products (ATMP) provide promising treatment options particularly for unmet clinical needs, such as progressive and chronic diseases where currently no satisfying treatment exists. Especially from the ATMP subclass of Tissue Engineered Products (TEPs), only a few have yet been translated from an academic setting to clinic and beyond. A reason for low numbers of TEPs in current clinical trials and one main key hurdle for TEPs is the cost and labor-intensive manufacturing process. Manual production steps require experienced personnel, are challenging to standardize and to scale up. Automated manufacturing has the potential to overcome these challenges, toward an increasing cost-effectiveness. One major obstacle for automation is the control and risk prevention of cross contaminations, especially when handling parallel production lines of different patient material. These critical steps necessitate validated effective and efficient cleaning procedures in an automated system. In this perspective, possible technologies, concepts and solutions to existing ATMP manufacturing hurdles are discussed on the example of a late clinical phase II trial TEP. In compliance to Good Manufacturing Practice (GMP) guidelines, we propose a dual arm robot based isolator approach. Our novel concept enables complete process automation for adherent cell culture, and the translation of all manual process steps with standard laboratory equipment. Moreover, we discuss novel solutions for automated cleaning, without the need for human intervention. Consequently, our automation concept offers the unique chance to scale up production while becoming more cost-effective, which will ultimately increase TEP availability to a broader number of patients. KW - ATMP KW - tissue engineering KW - GMP KW - manufacturing KW - autologous KW - cartilage regeneration KW - automation & robotics KW - automation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-244631 SN - 2296-858X VL - 8 ER -