bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of MAPK in governing lymphocyte adhesion to and migration across the microvasculature in inflammatory bowel disease
Authors: Scaldaferri Franco , Sans Miquel , Vetrano Stefania , Correale Carmen , Arena Vincenzo , Pagano Nico , Rando Giacomo , Romeo Fabio , Potenza Angelo E. , Repici Alessandro , Malesci Alberto , Danese Silvio 
Published: January 2009

AbstractLymphocyte recruitment is a key pathogenic event in inflammatory bowel disease (IBD). Adhesion of T cells to human intestinal microvascular endothelial cells (HIMEC) is mediated by ICAM‐1, VCAM‐1 and fractalkine (FKN), but the signaling molecules that orchestrate this process have yet to be identified. Because MAPK play an important role in the response of many cell types to pro‐inflammatory stimuli, we assessed the functional role of p38 MAPK, p42/44 MAPK and JNK in the regulation of lymphocyte adhesion to and chemotaxis across the microvasculature in IBD. We found that the MAPK were phosphorylated in the bowel microvasculature and human intestinal fibroblasts of patients with IBD but not of healthy individuals. Stimulation of HIMEC with TNF‐α triggered phosphorylation of the MAPK, and up‐regulation of VCAM‐1, FKN and ICAM‐1. Blockade of p38 decreased the expression of all MAPK by 50% (p<0.01), whereas inhibition of p42/44 decreased the expression of ICAM‐1 and FKN by 50% (p<0.01). Treatment of human intestinal fibroblasts with TNF‐α elicited production of IL‐8 and MCP‐1, which was reduced (p<0.05) by blockade of p38 and p42/44. Finally, blockade of p38 and p42/44 reduced lymphocyte adhesion to (p<0.05) and transmigration across (p<0.05) HIMEC monolayers. These findings suggest a critical role for MAPK in governing lymphocyte influx into the gut in IBD patients, and their blockade may offer a molecular target for blockade of leukocyte recruitment to the intestine.
Tyrosine phosphorylation of scavenger receptor cysteine‐rich WC1 is required for the WC1‐mediated potentiation of TCR‐induced T‐cell proliferation
Authors: Wang Fei , Herzig Carolyn , Ozer Dar , Baldwin Cynthia L. , Telfer Janice C. 
Published: January 2009

AbstractWorkshop cluster 1 (WC1) molecules are transmembrane glycoproteins uniquely expressed by γδ T cells. They belong to the scavenger receptor cysteine‐rich superfamily and are encoded by a multi‐gene family, which is divided on the basis of antibody reactivity, into three groups, WC1.1, WC1.2, and WC1.3. The potential role of WC1 as a co‐stimulatory molecule for the γδ TCR is suggested by the presence of several tyrosine‐based motifs in their intracellular domains. In this study, we found that WC1 was constitutively phosphorylated in ex vivo bovine γδ T cells and associated with src family tyrosine kinases. Crosslinking of WC1 molecules resulted in an increase in WC1 phosphorylation and co‐crosslinking of WC1 and γδ TCR together prolonged WC1 phosphorylation. We identified the second tyrosine residue as the primary phosphorylation target in WC1.1 and WC1.2 intracellular sequences in both in vitro and in vivo assays. The cytoplasmic tails of WC1.1 and WC1.2 were phosphorylated on serine and PKC activity was required for PMA‐induced endocytosis of WC1.1 or WC1.2. We found that phosphorylation of the second tyrosine in the WC1 cytoplasmic domain was required for the WC1‐mediated potentiation of TCR‐induced T‐cell proliferation, suggesting that WC1 acts as a co‐stimulatory molecule for γδ TCR.
PPP1R9B (Neurabin 2): Involvement and dynamics in the NK immunological synapse
Authors: Meng Xiaobo , Kanwar Namita , Du Qiujiang , Goping Ing S. , Bleackley R. Chris , Wilkins John A. 
Published: January 2009

AbstractThe NK immunological synapse (NKIS) is a dynamic structure dependent on the assembly of membrane, cytoskeletal and signaling components. These serve to focus and generate stimuli for adhesion and orientation of the cytoskeleton for targeted cytolytic granule release. Previous studies have demonstrated the importance of the cytoskeleton in these processes. We previously identified PPP1R9B (neurabin 2, spinophilin) as a cytoskeletal component of the NK‐like cell line YTS. We demonstrate that (i) PPP1R9B gradually accumulates at the NKIS in a maturation stage‐dependent manner; (ii) it mimics the early kinetics of actin recruitment to the NKIS but it precedes actin departure from the site; (iii) it is recruited by CD18 stimulation but not by CD28 ligation; (iv) it is required for the maintenance of the cortical F‐actin organization in the YTS cells and knocking down PPP1R9B reduces the frequency of YTS–target cell conjugation, possibly due to the collapsed F‐actin cytoskeleton in these cells. These results indicate that PPP1R9B is required for synapse formation in the NK cells and suggest that it may be involved in the maintenance of cellular architecture by regulation of actin assembly, possibly acting to stabilize the NKIS until granule release is eminent.
CD25+ Treg specifically suppress auto‐Ab generation against pancreatic tissue autoantigens
Authors: Ludwig‐Portugall Isis , Hamilton‐Williams Emma E. , Gotot Janine , Kurts Christian 
Published: January 2009

AbstractTo study B‐cell tolerance against non‐lymphoid tissue autoantigens, we generated transgenic rat insulin promoter (RIP)‐OVA/hen egg lysozyme (HEL) mice expressing the model antigens, OVA and HEL, in pancreatic islets. Their vaccination with OVA or HEL induced far less auto‐Ab titers compared with non‐transgenic controls. Depletion of CD25+ cells during immunization completely restored auto‐Ab production, but did not affect antibodies against a foreign control antigen. Depletion at later time‐points was not effective. OVA‐specific CD25+ FoxP3+ Treg were more frequent in the autoantigen‐draining pancreatic LN than in other secondary lymphatics of RIP‐OVA/HEL mice. Consistently, B cells were suppressed in that LN and also in the spleen, which is known to concentrate circulating antigen, such as the antigens used for vaccination. Suppression involved preventing expansion of autoreactive B cells in response to autoantigen, reducing antibody production per B‐cell and isotype changes. These findings demonstrate that CD25+ Treg suppress auto‐Ab production against non‐lymphoid tissue antigens in an antigen‐specific manner.
In vivo application of mAb directed against the γδ TCR does not deplete but generates “invisible” γδ T cells
Authors: Koenecke Christian , Chennupati Vijaykumar , Schmitz Susanne , Malissen Bernard , Förster Reinhold , Prinz Immo 
Published: January 2009

AbstractmAb targeting the γδ TCR have been used for γδ T‐cell depletion with varying success. Although the depletion‐capacity of the anti‐γδ TCR mAb clone GL3 has been disputed repeatedly, many groups continue to use γδ T‐cell depletion protocols involving the mAb clone UC7‐13D5 and find significant biological effects. We show here that treatment with both GL3 and UC7‐13D5 antibodies does not deplete γδ T cells in vivo, but rather leads to TCR internalization and thereby generates “invisible” γδ T cells. We addressed this issue using anti‐γδ TCR mAb injections into WT mice as well as into reporter TCR delta locus‐histone 2B enhanced GFP knock‐in mice, in which γδ T cells can be detected based on an intrinsic green fluorescence. Importantly, the use of TCR delta locus‐histone 2B enhanced GFP mice provided here for the first time direct evidence that the “depleted” γδ T cells were actually still present. Our results show further that GL3 and UC7‐13D5 mAb are in part cross‐competing for the same epitope. Assessed by activation markers, we observed in vitro and in vivo activation of γδ T cells through mAb. We conclude that γδ T‐cell depletion experiments must be evaluated with caution and discuss the implications for future studies on the physiological functions of γδ T cells.
Two major groups of rat NKR‐P1 receptors can be distinguished based on chromosomal localization, phylogenetic analysis and Clr ligand binding
Authors: Kveberg Lise , Dai Ke‐Zheng , Westgaard Ingunn H. , Daws Michael R. , Fossum Sigbjørn , Naper Christian , Vaage John T. 
Published: January 2009

AbstractA major subset of non‐alloreactive NK cells in PVG strain rats is generally low in Ly49 receptors, but expresses the rat NKR‐P1BPVG receptor (previously termed NKR‐P1C). The NKR‐P1B+ NK subset is inhibited by a non‐polymorphic target cell ligand, which we have shown here to be a C‐type lectin‐related molecule (Clr). Clr11 ligates two divergent NKR‐P1B alleles as judged by an NFAT‐driven reporter assay, and inhibits NK‐cell cytotoxicity of NKR‐P1B+ NK cells. Clr11 also interacts with the prototypic NKR‐P1A receptor and exerts a stimulatory influence on NK lysis. NKR‐P1A and B are encoded by adjacent genes in the proximal part of the NK gene complex and show close sequence homology in their extracellular region. They diverge from another pair, NKR‐P1F and ‐G, which is encoded by a second, distal Nkrp1 gene cluster. NKR‐P1F and ‐G bind an overlapping panel of Clr ligands, but not Clr11. Rat Clr molecules appear to be constitutively expressed by hematopoietic cells; expression in tumor cell lines is more variable. The data show the existence of two phylogenetic groups of NKR‐P1 molecules, which demonstrate conservation of ligand‐binding properties independent of signaling function.
Modelling pathways of CD8+ T‐cell differentiation
Authors: Yates Andrew 
Published: January 2009

AbstractIn an immune response to infection, naïve T lymphocytes proliferate and give rise to a heterogeneous population of effector and memory cells. How is this diversity generated, and how can it be manipulated? Answering these questions requires an understanding of the lineage relationships between different effector and memory‐cell subsets, but these relationships remain to be identified definitively. In this issue of the European Journal of Immunology, a study moves us closer to this goal by combining a mathematical model and data from influenza infections in mice to support the hypothesis that CD8+ T‐cell differentiation is strongly coupled to cell division.
Cover Picture: Eur. J. Immunol. 1/09
Authors: Sheng Kuo‐Ching , van Spriel Annemiek B. , Gartlan Kate H. , Sofi Mariam , Apostolopoulos Vasso , Ashman Leonie , Wright Mark D. 
Published: January 2009

AbstractThe cover image is a stylised depiction of tetraspanin‐deficient DC supplied by Sheng et al., the authors of Tetraspanins CD37 and CD151 differentially regulate Ag presentation and T‐cell co‐stimulation by DC (pp. 50‐55). Bone‐marrow‐derived DC were stimulated with LPS and allowed to adhere to glass coverslips. MHC class II was detected by mAb (green/red/orange stainings) and the nuclei stained with TOPRO‐3 (blue). Cells were visualised under confocal microscopy and a collage of images generated using Photoshop CS2.
Regiospecific distribution of fatty acids in triacylglycerols and phospholipids from broad beans (Vicia faba)
Authors: Yoshida Hiromi , Tomiyama Yuka , Yoshida Naoko , Mizushina Yoshiyuki 
Published: January 2009

AbstractRegiospecific distributions of fatty acids of triacylglycerols (TAG) and phospholipids (PL) separated from broad beans (Vicia faba) of four cultivars (Minpo, Sanuki, Nintoku and Sanren) were investigated. The major lipid components were PL (47.5–50.5 wt‐%) and TAG (47.7–50.1 wt‐%), while steryl esters, hydrocarbons, free fatty acids, diacylglycerols and monoacylglycerols were present in minor proportions (1.6–2.4 wt‐%). The PL components isolated from the four cultivars were phosphatidylcholine (56.4–58.4 wt‐%), phosphatidylethanolamine (20.3–21.7 wt‐%) and phosphatidylinositol (16.6–18.6 wt‐%). Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among these PL. The principal characteristics of the fatty acid distribution in the TAG and PL were evident in the beans: Unsaturated fatty acids were predominantly concentrated in the sn‐2 position while saturated fatty acids primarily occupied the sn‐1 or sn‐3 position in these lipids. The lipid components and fatty acid distributions were almost the same in the four cultivars and were not influenced by genetic variability and planting location. These results could be useful information to both consumers and producers for the manufacture of traditional broad bean foods in Japan.
Enantiospecific Synthesis of a Protected Equivalent of APTO, the β‐Amino Acid Fragment of Microsclerodermins C and D, by Aziridino‐γ‐lactone Methodology
Authors: Tarrade‐Matha Aurélie , Valle Marcelo Siqueira , Tercinier Pierre , Dauban Philippe , Dodd Robert H. 
Published: January 2009

AbstractThe efficient synthesis of a protected form of (2S,3R,4S,5S,7E)‐3‐amino‐8‐phenyl‐2,4,5‐trihydroxyoct‐7‐enoic acid (APTO), the α‐hydroxy β‐amino acid component of microsclerodermins C and D, 23‐membered cyclic peptides isolated from lithistid sponges, is described. The strategy is based on the preparation of the aziridino‐γ‐lactone 46 from L‐gulose by a procedure previously developed in our laboratory for simpler substrates. Regioselective opening of the aziridine at C‐2 by acetate anion, an intrinsic reactivity pattern of aziridino‐γ‐lactones, followed by a Heck reaction to install the terminal phenyl group, provides lactone 48. This, a lactonized form of APTO, can be considered an activated building block for the synthesis of microsclerodermins C and D or their analogues, as demonstrated by its subsequent reaction with a benzylamine to give the carboxamide 51. This represents the first example of the use of an aziridino‐γ‐lactone for the stereoselective synthesis of an α‐substituted β‐amino acid derivative. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Dizinc Phosphohydrolase Model Built on a m‐Terphenyl Scaffold and Its Use in Indicator Displacement Assays for Pyrophosphate Under Physiological Conditions (Eur. J. Org. Chem. 3/2009)
Authors: Coggins Michael K. , Parker Austa M. , Mangalum Anshuman , Galdamez Gabriela A. , Smith Rhett C. 
Published: January 2009

AbstractThe cover picture shows a dizinc phosphohydrolase model built on a m‐terphenyl scaffold that binds pyrophosphate with concomitant displacement of complexometric indicators; this leads to dramatic color changes that can be detected visually and quantified spectroscopically. Details are discussed in the article by R. C. Smith et al. on p. 343 ff.
Dielectrophoretic capture of mammalian cells using transparent indium tin oxide electrodes in microfluidic systems
Authors: Sankaran Bharat , Racic Milena , Tona Alessandro , Rao Mulpuri V. , Gaitan Michael , Forry Samuel P. 
Published: January 2009

AbstractTransparent indium tin oxide microelectrodes were fabricated and used to immobilize suspended NIH 3T3 fibroblast cells by positive dielectrophoresis. The indium tin oxide electrodes facilitated microscopic observation of immobilized cells compared with opaque metallized electrodes. Dielectrophoresis was used to capture arrays of individual cells and form small cell clusters within a microfluidic network. The extent of cellular immobilization (no‐cell, single‐cell, or multiple‐cell capture) was correlated with the applied voltage and inversely with the flow velocity. Specific conditions yielding predominantly single‐cell capture were identified. The viability of immobilized cells was confirmed using fluorescence microscopy.
Fabrication of PMMA CE microchips by infrared‐assisted polymerization
Authors: Chen Yun , Duan Haotian , Zhang Luyan , Chen Gang 
Published: January 2009

AbstractIn this report, a method based on the infrared‐assisted polymerization of methyl methacrylate has been developed for the rapid fabrication of PMMA CE microchips. Methyl methacrylate containing AIBN was allowed to prepolymerize in a water bath to form a fast‐curing molding solution that was subsequently sandwiched between a silicon template and a piece of 1 mm‐thick PMMA plate. The images of microchannels on the silicon template were precisely replicated into the synthesized PMMA substrates during the infrared‐assisted polymerization of the molding solution. The polymerization could be completed within 50 min at 50°C. The obtained channel plate was subsequently bonded to a piece of PMMA cover sheet to form a microchip with the aid of heat and pressure. The new fabrication approach obviates the need for special equipment and significantly simplifies the process of fabricating PMMA microchips. The attractive performance of the obtained PMMA microchips has been demonstrated in connection with contactless conductivity detection for the separation and detection of ionic species.
Dielectrophoretic characterization of erythrocytes: Positive ABO blood types
Authors: Srivastava Soumya K. , Daggolu Prashant R. , Burgess Shane C. , Minerick Adrienne R. 
Published: January 2009

AbstractDielectrophoretic manipulation of erythrocytes/red blood cells is investigated as a tool to identify blood type for medical diagnostic applications. Positive blood types of the ABO typing system (A+, B+, AB+ and O+) were tested and cell responses quantified. The dielectrophoretic response of each blood type was observed in a platinum electrode microdevice, delivering a field of 0.025Vpp/μm at 1 MHz. Responses were recorded via video microscopy for 120 s and erythrocyte positions were tabulated at 20–30 s intervals. Both vertical and horizontal motions of erythrocytes were quantified via image object recognition, object tracking in MATLAB, binning into appropriate electric field contoured regions (wedges) and statistical analysis. Cells of O+ type showed relatively attenuated response to the dielectrophoretic field and were distinguished with greater than 95% confidence from all the other three blood types. AB+ cell responses differed from A+ and B+ blood types likely because AB+ erythrocytes express both the A and B glycoforms on their membrane. This research suggests that dielectrophoresis of untreated erythrocytes beyond simple dilution depends on blood type and could be used in portable blood typing devices.
Development of an acrylate monolith in a cyclo‐olefin copolymer microfluidic device for chip electrochromatography separation
Authors: Faure Karine , Albert Monique , Dugas Vincent , Crétier Gérard , Ferrigno Rosaria , Morin Pierre , Rocca Jean‐Louis 
Published: January 2009

AbstractAn acrylate monolith has been synthesized into a cyclic olefin copolymer microdevice for reversed‐phase electrochromatography purposes. Microchannels, designed by hot embossing, were filled up with an acrylate monolith to serve as a hydrophobic stationary phase. A lauryl acrylate monolith was formulated to suit the hydrophobic material, by implementing 100% organic porogenic solvent. This new composition was tested in capillary prior to its transfer into the microfluidic device. Surface functionalization of the cyclic olefin copolymer surface was applied using UV‐grafting technique to improve the covalent attachment of this monolith to the plastic walls of the microfluidic chip. The on‐chip performances of this monolith were evaluated in detail for the reversed‐phase electrochromatographic separation of polycyclic aromatic hydrocarbons, with plate heights reaching down to 10 μm when working at optimal velocity.
Dual‐color microchip electrophoresis with single‐photon avalanche diodes: Application to mutation detection
Authors: Stenirri Stefania , Cretich Marina , Rech Ivan , Restelli Alessandro , Ghioni Massimo , Cova Sergio , Ferrari Maurizio , Cremonesi Laura , Chiari Marcella 
Published: January 2009

AbstractA novel microchip electrophoresis instrument based on single‐photon avalanche diodes was used for the molecular characterization of mutations in disease genes. The identification of the main mutation causing cystic fibrosis, named ΔF508, by the Amplification Refractory Mutation System was used to validate the technology. In our implemented protocol the wild‐type and mutant allele‐specific primers are labeled with Cy5 and Cy5.5, respectively. The protocol enables the amplification of the DNA sample in a single PCR. The genotype was deduced from the fluorescence of the amplicons run in the CE microchip. Validation on 15 DNA samples from either homozygous wild‐type or heterozygous and homozygous mutated control subjects proved the complete reliability of the system, thus confirming its high diagnostic potential.
Microchip assays for screening monoclonal antibody product quality
Authors: Chen Xiaoyu , Tang Kaiyan , Lee Maximilian , Flynn Gregory C. 
Published: January 2009

AbstractMicrochip CE‐SDS was evaluated as a high‐throughput alternative to conventional CE‐SDS for monitoring monoclonal antibody protein quality. A commercial instrument (LabChip® 90) was used to separate dodecyl sulfate coated proteins through a sieving polymer based on the proteins' sizes. Under reducing conditions, the microchip CE‐SDS separation was similar to that of conventional CE‐SDS, providing reasonable resolution of the non‐glycosylated and the glycosylated heavy chains. The fluorescence detection on LabChip 90 using non‐covalent fluorescent labeling method was about as sensitive as the 220 nm UV detection used in a conventional CE instrument. A simple glycan typing assay was developed for the reducing microchip CE‐SDS format. Antibodies, either pure or in crude cell culture media are treated with Endoglycosidase H, which specifically cleaves the hybrid and high mannose type glycans. A heavy chain migration shift on reducing CE‐SDS resulting from the loss of glycan is used to measure the level of high mannose/hybrid type glycans as a percentage of the total glycans. Microchip CE‐SDS, under both non‐reducing and reducing conditions, can be used in a variety of antibody product screening assays. The microchip analyses provide sufficient resolution and sensitivity for this purpose but on a time scale approximately 70 times faster (41 s versus 50 min per sample) than conventional CE separation under typical operational conditions.
Electrokinetic instability effects in microchannels with and without nanofilm coatings
Authors: Fu Lung‐Ming , Hong Ting‐Fu , Wen Chih‐Yung , Tsai Chien‐Hsiung , Lin Che‐Hsin 
Published: January 2009

AbstractThis paper presents a parametric experimental investigation into the electrokinetic instability (EKI) phenomenon within three different types of microfluidic device, namely T‐type, cross‐shaped, and cross‐form with an expansion configuration. The critical electric field strength at which the EKI phenomenon is induced is examined as a function of the conductivity ratio, the microchannel width, the expansion ratio, and the surface treatment of the microchannel walls. It is found that the critical electric field strength associated with the onset of EKI is strongly dependent on the conductivity ratio of the two samples within the microfluidic device and reduces as the channel width increases. The surfaces of the microchannel walls are coated with hydrophilic or hydrophobic organic‐based spin‐on‐glass (SOG) nanofilms for glass‐based microchips. The experimental results indicate that no significant difference exists in the critical electric field strengths in the hydrophilic or hydrophobic SOG‐coated microchannels, respectively. However, for a given conductivity ratio and microchannel width, the critical strength of the electric field is slightly lower in the SOG‐coated microchannels than in the non‐coated channels. In general, the results presented in this study demonstrate the potential for designing and controlling on‐chip assays requiring the manipulation of samples with high conductivity gradients, and provide a useful general reference for avoiding EKI effects in capillary electrophoresis analysis applications.