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941.
Philipp Nold Cornelia Brendel Andreas Neubauer Gregor Bein Holger Hackstein 《Biochemical and biophysical research communications》2013,430(1):325-330
Mesenchymal stroma cells (MSC) are increasingly recognized for various applications of cell-based therapies such as regenerative medicine or immunomodulatory treatment strategies. Standardized large-scale expansions of MSC under good manufacturing practice (GMP)-compliant conditions avoiding animal derived components are mandatory for further evaluation of these novel therapeutic approaches in clinical trials.We applied a novel automated hollow fiber cell expansion system (CES) for in vitro expansion of human bone marrow derived MSC employing a GMP-compliant culture medium with human platelet lysate (HPL). Between 8 and 32 ml primary bone marrow aspirate were loaded into the hollow fiber CES and cultured for 15–27 days. 2–58 million MSC were harvested after primary culture. Further GMP-compliant cultivation of second passage MSC for 13 days led to further 10–20-fold enrichment. Viability, surface antigen expression, differentiation capacity and immunosuppressive function of MSC cultured in the hollow fiber CES were in line with standard criteria for MSC definition. We conclude that MSC can be enriched from primary bone marrow aspirate in a GMP-conform manner within a closed hollow fiber bioreactor and maintain their T lymphocyte inhibitory capacity. Standardized and reliable conditions for large scale MSC expansion pave the way for safe applications in humans in different therapeutic approaches. 相似文献
942.
Biallelic SZT2 Mutations Cause Infantile Encephalopathy with Epilepsy and Dysmorphic Corpus Callosum
Lina Basel-Vanagaite Tova Hershkovitz Eli Heyman Miquel Raspall-Chaure Naseebullah Kakar Pola Smirin-Yosef Marta Vila-Pueyo Liora Kornreich Holger Thiele Harald Bode Irina Lagovsky Dvir Dahary Ami Haviv Monika Weisz Hubshman Metsada Pasmanik-Chor Peter Nürnberg Doron Gothelf Christian Kubisch Mordechai Shohat Alfons Macaya Guntram Borck 《American journal of human genetics》2013
943.
Gordon J. Hildick-Smith Jeffrey D. Cooney Caterina Garone Laura S. Kremer Tobias B. Haack Jonathan N. Thon Non Miyata Daniel S. Lieber Sarah E. Calvo H. Orhan Akman Yvette Y. Yien Nicholas C. Huston Diana S. Branco Dhvanit I. Shah Matthew L. Freedman Carla M. Koehler Joseph E. Italiano Jr. Andreas Merkenschlager Skadi Beblo Tim M. Strom Thomas Meitinger Peter Freisinger M. Alice Donati Holger Prokisch Vamsi K. Mootha Salvatore DiMauro Barry H. Paw 《American journal of human genetics》2013
944.
Gordon?J. Hildick-Smith Jeffrey?D. Cooney Caterina Garone Laura?S. Kremer Tobias?B. Haack Jonathan?N. Thon Non Miyata Daniel?S. Lieber Sarah?E. Calvo H.?Orhan Akman Yvette?Y. Yien Nicholas?C. Huston Diana?S. Branco Dhvanit?I. Shah Matthew?L. Freedman Carla?M. Koehler Joseph?E. Italiano Jr. Andreas Merkenschlager Skadi Beblo Tim?M. Strom Thomas Meitinger Peter Freisinger M.?Alice Donati Holger Prokisch Vamsi?K. Mootha Salvatore DiMauro Barry?H. Paw 《American journal of human genetics》2013,93(5):906-914
We used exome sequencing to identify mutations in sideroflexin 4 (SFXN4) in two children with mitochondrial disease (the more severe case also presented with macrocytic anemia). SFXN4 is an uncharacterized mitochondrial protein that localizes to the mitochondrial inner membrane. sfxn4 knockdown in zebrafish recapitulated the mitochondrial respiratory defect observed in both individuals and the macrocytic anemia with megaloblastic features of the more severe case. In vitro and in vivo complementation studies with fibroblasts from the affected individuals and zebrafish demonstrated the requirement of SFXN4 for mitochondrial respiratory homeostasis and erythropoiesis. Our findings establish mutations in SFXN4 as a cause of mitochondriopathy and macrocytic anemia. 相似文献
945.
Krista M. Giglio Jiunn C. Fong Fitnat H. Yildiz Holger Sondermann 《Journal of bacteriology》2013,195(14):3277-3286
During the transition from a free-swimming, single-cell lifestyle to a sessile, multicellular state called a biofilm, bacteria produce and secrete an extracellular matrix comprised of nucleic acids, exopolysaccharides, and adhesion proteins. The Vibrio cholerae biofilm matrix contains three major protein components, RbmA, Bap1, and RbmC, which are unique to Vibrio cholerae and appear to support biofilm formation at particular steps in the process. Here, we focus on RbmA, a structural protein with an unknown fold. RbmA participates in the early cell-cell adhesion events and is found throughout the biofilm where it localizes to cell-cell contact sites. We determined crystal structures of RbmA and revealed that the protein folds into tandem fibronectin type III (FnIII) folds. The protein is dimeric in solution and in crystals, with the dimer interface displaying a surface groove that is lined with several positively charged residues. Structure-guided mutagenesis studies establish a crucial role for this surface patch for RbmA function. On the basis of the structure, we hypothesize that RbmA serves as a tether by maintaining flexible linkages between cells and the extracellular matrix. 相似文献
946.
947.
Anke Jaudszus Michael Gruen Bernhard Watzl Christina Ness Alexander Roth Alfred Lochner Dagmar Barz Holger Gabriel Michael Rothe Gerhard Jahreis 《Journal of lipid research》2013,54(4):923-935
Despite their beneficial anti-inflammatory properties, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) may increase the infection risk at high doses, likely by generating an immune-depressed state. To assess the contribution of different immune cell populations to the immunomodulatory fatty acid effect, we comparatively investigated several aspects of inflammation in human T-helper (Th) cells and monocytes. Both fatty acids, but DHA to a lesser extent compared with EPA, selectively and dose-dependently reduced the percentage of cytokine-expressing Th cells in a peroxisome proliferator-activated receptor (PPAR)γ-dependent fashion, whereas the expression of the cell surface marker CD69 was unaltered on activated T cells. In monocytes, both EPA and DHA increased interleukin (IL)-10 without affecting tumor necrosis factor (TNF)-α and IL-6. Cellular incorporation of EPA and DHA occurred mainly at the expense of arachidonic acid. Concomitantly, thromboxane B (TXB)2 and leukotriene B (LTB)4 in supernatants decreased, while levels of TXB3 and LTB5 increased. This increase was independent of activation and in accordance with cyclooxygenase expression patterns in monocytes. Moreover, EPA and DHA gave rise to a variety of mono- and trihydroxy derivatives of highly anti-inflammatory potential, such as resolvins and their precursors. Our results suggest that EPA and DHA do not generally affect immune cell functions in an inhibitory manner but rather promote pro-resolving responses. 相似文献
948.
Comparison of periplasmic and intracellular expression of Arabidopsis thionin proproteins in E. coli
Amjad Abbas Stephan Plattner Kausar Hussain Shah Holger Bohlmann 《Biotechnology letters》2013,35(7):1085-1091
Thionins are antimicrobial plant peptides produced as preproproteins consisting of a signal peptide, the thionin domain, and a so-called acidic domain. Only thionin itself has been isolated from plants. To study the processing of the precursor, it has to be produced in a heterologous system. Since both domains contain several cysteines and, due to the known antimicrobial activity of the thionin, we tested the expression of all four Arabidopsis proproteins as fusion proteins. Periplasmic expression as fusion with maltose binding protein was not successful but cytoplasmic expression as His-tagged TRX fusion proteins with a TEV recognition sequence resulted in proteins of correct size. Use of the SHuffle strain C3030 further improved the expression. Fusion proteins inhibited growth of Escherichia coli. They could be cleaved by TEV protease, releasing authentic proproteins without any additional amino acid at the N-terminus. 相似文献
949.
The Vjetrenica cave in the Dinaric Karst hosts a worldwide extraordinarily high cave biodiversity. Beside a diverse and specialized cave fauna, sprout-like formations attached to the bed of the cave stream were observed and described, but not further characterized, almost a century ago. Here we investigated these sprout-like microbial aggregates by the rRNA approach and detailed microscopy. Based on fluorescence in situ hybridization and ultrastructural analysis, the sprout-like formations are morphologically highly organized, and their core consists of a member of a novel deep-branching lineage in the bacterial phylum Nitrospirae. This organism displays an interesting cellular ultrastructure with different kinds of cytoplasmic inclusions and is embedded in a thick extracellular matrix, which contributes to the stability and shape of the aggregates. This novel bacterium has been provisionally classified as “Candidatus Troglogloea absoloni.” The surface of the sprout-like aggregates is more diverse than the core. It is colonized by a bacterial biofilm consisting primarily of filamentous Betaproteobacteria, whereas other microbial populations present in the crust include members of the Bacteriodetes, Gammaproteobacteria, Actinombacteria, Alphaproteobacteria, and Planctomycetes, which are intermingled with mineral inclusions. This study represents the first thorough molecular and ultrastructural characterization of the elusive sprout-like bacterial aggregates, which are also found in other cave systems of the Dinaric Karst. The discovery of Ca. Troglogloea absoloni contributes to the known biodiversity of subterranean ecosystems and especially of macroscopic structures formed in caves by microorganisms, whose composition and ecological function often remain enigmatic. 相似文献
950.
Yi Wang Xiangzhen Li Caroline B. Milne Holger Janssen Weiyin Lin Gloria Phan Huiying Hu Yong-Su Jin Nathan D. Price Hans P. Blaschek 《Applied and environmental microbiology》2013,79(19):5853-5863
Clostridium beijerinckii is a well-known solvent-producing microorganism with great potential for biofuel and biochemical production. To better understand and improve the biochemical pathway to solvents, the development of genetic tools for engineering C. beijerinckii is highly desired. Based on mobile group II intron technology, a targetron gene knockout system was developed for C. beijerinckii in this study. This system was successfully employed to disrupt acid production pathways in C. beijerinckii, leading to pta (encoding phosphotransacetylase)- and buk (encoding butyrate kinase)-negative mutants. In addition to experimental characterization, the mutant phenotypes were analyzed in the context of our C. beijerinckii genome-scale model. Compared to those of the parental strain (C. beijerinckii 8052), acetate production in the pta mutant was substantially reduced and butyrate production was remarkably increased, while solvent production was dependent on the growth medium. The pta mutant also produced much higher levels of lactate, suggesting that disrupting pta influenced the energy generation and electron flow pathways. In contrast, acetate and butyrate production in the buk mutant was generally similar to that of the wild type, but solvent production was consistently 20 to 30% higher and glucose consumption was more rapid and complete. Our results suggest that the acid and solvent production of C. beijerinckii can be effectively altered by disrupting the acid production pathways. As the gene disruption method developed in this study does not leave any antibiotic marker in a disrupted allele, multiple and high-throughput gene disruption is feasible for elucidating genotype and phenotype relationships in C. beijerinckii. 相似文献