1,472 research outputs found

    Cisplatin induces tolerogenic dendritic cells in response to TLR agonists via the abundant production of IL-10, thereby promoting Th2-and Tr1-biased T-cell immunity

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    Although many advantageous roles of cisplatin (cis-diamminedichloroplatinum (II), CDDP) have been reported in cancer therapy, the immunomodulatory roles of cisplatin in the phenotypic and functional alterations of dendritic cells (DCs) are poorly understood. Here, we investigated the effect of cisplatin on the functionality of DCs and the changes in signaling pathways activated upon toll-like receptor (TLR) stimulation. Cisplatin-treated DCs down-regulated the expression of cell surface molecules (CD80, CD86, MHC class I and II) and up-regulated endocytic capacity in a dose-dependent manner. Upon stimulation with various TLR agonists, cisplatin-treated DCs showed markedly increased IL-10 production through activation of the p38 MAPK and NF-kappa B signaling pathways without altering the levels of TNF-alpha and IL-12p70, indicating the cisplatin-mediated induction of tolerogenic DCs. This effect was dependent on the production of IL-10 from DCs, as neither DCs isolated from IL-10(-/-) mice nor IL-10-neutralized DCs generated tolerogenic DCs. Interestingly, DCs that were co-treated with cisplatin and lipopolysaccharide (LPS) exhibited a decreased immunostimulatory capacity for inducing the proliferation of Th1- and Th17-type T cells; instead, these DCs contributed to Th2-type T cell immunity. Furthermore, in vitro and in vivo investigations revealed a unique T cell population, IL-10-producing CD3(+)CD4(+)LAG-3(+)CD49b(+)CD25(-)Foxp3(-) Tr1 cells, that was significantly increased without altering the Foxp3(+) regulatory T cell population. Taken together, our results suggest that cisplatin induces immune-suppressive tolerogenic DCs in TLR agonist-induced inflammatory conditions via abundant IL-10 production, thereby skewing Th cell differentiation towards Th2 and Tr1 cells. This relationship may provide cancer cells with an opportunity to evade the immune system.1123Ysciescopu

    Cisplatin induces tolerogenic dendritic cells in response to TLR agonists via the abundant production of IL-10, therby promoting Th2- and Tr1-biased T-cell immunity

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    Although many advantageous roles of cisplatin (cis-diamminedichloroplatinum (II), CDDP) have been reported in cancer therapy, the immunomodulatory roles of cisplatin in the phenotypic and functional alterations of dendritic cells (DCs) are poorly understood. Here, we investigated the effect of cisplatin on the functionality of DCs and the changes in signaling pathways activated upon toll-like receptor (TLR) stimulation. Cisplatin-treated DCs down-regulated the expression of cell surface molecules (CD80, CD86, MHC class I and II) and up-regulated endocytic capacity in a dose-dependent manner. Upon stimulation with various TLR agonists, cisplatintreated DCs showed markedly increased IL-10 production through activation of the p38 MAPK and NF-ÎșB signaling pathways without altering the levels of TNF-α and IL- 12p70, indicating the cisplatin-mediated induction of tolerogenic DCs. This effect was dependent on the production of IL-10 from DCs, as neither DCs isolated from IL-10- /- mice nor IL-10-neutralized DCs generated tolerogenic DCs. Interestingly, DCs that were co-treated with cisplatin and lipopolysaccharide (LPS) exhibited a decreased immunostimulatory capacity for inducing the proliferation of Th1- and Th17-type T cells; instead, these DCs contributed to Th2-type T cell immunity. Furthermore, in vitro and in vivo investigations revealed a unique T cell population, IL-10-producing CD3+CD4+LAG-3+CD49b+CD25-Foxp3- Tr1 cells, that was significantly increased without altering the Foxp3+ regulatory T cell population. Taken together, our results suggest that cisplatin induces immune-suppressive tolerogenic DCs in TLR agonistinduced inflammatory conditions via abundant IL-10 production, thereby skewing Th cell differentiation towards Th2 and Tr1 cells. This relationship may provide cancer cells with an opportunity to evade the immune system.1231sciescopu

    Structural changes of synthetic paulingite (Na,H-ECR-18) upon dehydration and CO2 adsorption

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    Funding: EPSRCThe structure of dehydrated calcined ECR-18, synthetic paulingite, topology type PAU, unit cell composition Na132H28Si512Al160O1344, has been determined by Rietveld refinement against synchrotron X-ray powder diffraction data. Upon dehydration the symmetry of Na,H-ECR-18 changes from Im3m to I 43m, with a corresponding decrease of cubic unit cell a parameter from 34.89412(1) A to 33.3488(3) A. This occurs as the framework distorts to afford closer coordination of Na+ cations by framework O atoms in 8-ring window sites of the seven cage types present. Na+ cations in 8R sites block the access of N2 molecules to the internal pore space at 77 K but CO2 adsorption at 308 K is observed, and is postulated to occur via a 'trapdoor' mechanism. In situ PXRD during CO2 adsorption at pressures up to 10 bar show reversible broadening of diffraction peaks that is attributed to local crystallographic strain.Publisher PDFPeer reviewe

    Signal-Regulated Pre-mRNA Occupancy by the General Splicing Factor U2AF

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    Alternative splicing of transcripts in a signal-dependent manner has emerged as an important concept to ensure appropriate expression of splice variants under different conditions. Binding of the general splicing factor U2AF to splice sites preceding alternatively spliced exons has been suggested to be an important step for splice site recognition. For splicing to proceed, U2AF has to be replaced by other factors. We show here that U2AF interacts with the signal-dependent splice regulator Sam68 and that forced expression of Sam68 results in enhanced binding of the U2AF65 subunit to an alternatively spliced pre-mRNA sequence in vivo. Conversely, the rapid signal-induced and phosphorylation-dependent interference with Sam68 binding to RNA was accompanied by reduced pre-mRNA occupancy of U2AF in vivo. Our data suggest that Sam68 can affect splice site occupancy by U2AF in signal-dependent splicing. We propose that the induced release of U2AF from pre-mRNA provides a regulatory step to control alternative splicing

    The inner centromere is a biomolecular condensate scaffolded by the chromosomal passenger complex.

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    The inner centromere is a region on every mitotic chromosome that enables specific biochemical reactions that underlie properties, such as the maintenance of cohesion, the regulation of kinetochores and the assembly of specialized chromatin, that can resist microtubule pulling forces. The chromosomal passenger complex (CPC) is abundantly localized to the inner centromeres and it is unclear whether it is involved in non-kinase activities that contribute to the generation of these unique chromatin properties. We find that the borealin subunit of the CPC drives phase separation of the CPC in vitro at concentrations that are below those found on the inner centromere. We also provide strong evidence that the CPC exists in a phase-separated state at the inner centromere. CPC phase separation is required for its inner-centromere localization and function during mitosis. We suggest that the CPC combines phase separation, kinase and histone code-reading activities to enable the formation of a chromatin body with unique biochemical activities at the inner centromere

    Back reaction, covariant anomaly and effective action

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    In the presence of back reaction, we first produce the one-loop corrections for the event horizon and Hawking temperature of the Reissner-Nordstr\"om black hole. Then, based on the covariant anomaly cancelation method and the effective action technique, the modified expressions for the fluxes of gauge current and energy momentum tensor, due to the effect of back reaction, are obtained. The results are consistent with the Hawking fluxes of a (1+1)-dimensional blackbody at the temperature with quantum corrections, thus confirming the robustness of the covariant anomaly cancelation method and the effective action technique for black holes with back reaction.Comment: 17 page

    Exclusive Leptoproduction of rho^0 Mesons from Hydrogen at Intermediate Virtual Photon Energies

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    Measurements of the cross section for exclusive virtual-photoproduction of rho^0 mesons from hydrogen are reported. The data were collected by the HERMES experiment using 27.5 GeV positrons incident on a hydrogen gas target in the HERA storage ring. The invariant mass W of the photon-nucleon system ranges from 4.0 to 6.0 GeV, while the negative squared four-momentum Q^2 of the virtual photon varies from 0.7 to 5.0 GeV^2. The present data together with most of the previous data at W > 4 GeV are well described by a model that infers the W-dependence of the cross section from the dependence on the Bjorken scaling variable x of the unpolarized structure function for deep-inelastic scattering. In addition, a model calculation based on Off-Forward Parton Distributions gives a fairly good account of the longitudinal component of the rho^0 production cross section for Q^2 > 2 GeV^2.Comment: 10 pages, 6 embedded figures, LaTeX for SVJour(epj) document class. Revisions: curves added to Fig. 1, several clarifications added to tex

    Spontaneous hyaline cartilage regeneration can be induced in an osteochondral defect created in the femoral condyle using a novel double-network hydrogel

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    <p>Abstract</p> <p>Background</p> <p>Functional repair of articular osteochondral defects remains a major challenge not only in the field of knee surgery but also in tissue regeneration medicine. The purpose is to clarify whether the spontaneous hyaline cartilage regeneration can be induced in a large osteochondral defect created in the femoral condyle by means of implanting a novel double-network (DN) gel at the bottom of the defect.</p> <p>Methods</p> <p>Twenty-five mature rabbits were used in this study. In the bilateral knees of each animal, we created an osteochondral defect having a diameter of 2.4-mm in the medial condyle. Then, in 21 rabbits, we implanted a DN gel plug into a right knee defect so that a vacant space of 1.5-mm depth (in Group I), 2.5-mm depth (in Group II), or 3.5-mm depth (in Group III) was left. In the left knee, we did not apply any treatment to the defect to obtain the control data. All the rabbits were sacrificed at 4 weeks, and the gross and histological evaluations were performed. The remaining 4 rabbits underwent the same treatment as used in Group II, and real-time PCR analysis was performed at 4 weeks.</p> <p>Results</p> <p>The defect in Group II was filled with a sufficient volume of the hyaline cartilage tissue rich in proteoglycan and type-2 collagen. The Wayne's gross appearance and histology scores showed that Group II was significantly greater than Group I, III, and Control (p < 0.012). The relative expression level of type-2 collagen, aggrecan, and SOX9 mRNAs was significantly greater in Group II than in the control group (p < 0.023).</p> <p>Conclusions</p> <p>This study demonstrated that spontaneous hyaline cartilage regeneration can be induced <it>in vivo </it>in an osteochondral defect created in the femoral condyle by means of implanting the DN gel plug at the bottom of the defect so that an approximately 2-mm deep vacant space was intentionally left in the defect. This fact has prompted us to propose an innovative strategy without cell culture to repair osteochondral lesions in the femoral condyle.</p

    Measurement of the Forward-Backward Asymmetry in the B -> K(*) mu+ mu- Decay and First Observation of the Bs -> phi mu+ mu- Decay

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    We reconstruct the rare decays B+→K+ÎŒ+Ό−B^+ \to K^+\mu^+\mu^-, B0→K∗(892)0ÎŒ+Ό−B^0 \to K^{*}(892)^0\mu^+\mu^-, and Bs0→ϕ(1020)ÎŒ+Ό−B^0_s \to \phi(1020)\mu^+\mu^- in a data sample corresponding to 4.4fb−14.4 {\rm fb^{-1}} collected in ppˉp\bar{p} collisions at s=1.96TeV\sqrt{s}=1.96 {\rm TeV} by the CDF II detector at the Fermilab Tevatron Collider. Using 121±16121 \pm 16 B+→K+ÎŒ+Ό−B^+ \to K^+\mu^+\mu^- and 101±12101 \pm 12 B0→K∗0ÎŒ+Ό−B^0 \to K^{*0}\mu^+\mu^- decays we report the branching ratios. In addition, we report the measurement of the differential branching ratio and the muon forward-backward asymmetry in the B+B^+ and B0B^0 decay modes, and the K∗0K^{*0} longitudinal polarization in the B0B^0 decay mode with respect to the squared dimuon mass. These are consistent with the theoretical prediction from the standard model, and most recent determinations from other experiments and of comparable accuracy. We also report the first observation of the Bs0→ϕΌ+Ό−decayandmeasureitsbranchingratioB^0_s \to \phi\mu^+\mu^- decay and measure its branching ratio {\mathcal{B}}(B^0_s \to \phi\mu^+\mu^-) = [1.44 \pm 0.33 \pm 0.46] \times 10^{-6}using using 27 \pm 6signalevents.Thisiscurrentlythemostrare signal events. This is currently the most rare B^0_s$ decay observed.Comment: 7 pages, 2 figures, 3 tables. Submitted to Phys. Rev. Let

    Phenotypic and Transcriptomic Response of Auxotrophic Mycobacterium avium Subsp. paratuberculosis leuD Mutant under Environmental Stress

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    Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of severe gastroenteritis in cattle. To gain a better understanding of MAP virulence, we investigated the role of leuD gene in MAP metabolism and stress response. For this, we have constructed an auxotrophic strain of MAP by deleting the leuD gene using allelic exchange. The wildtype and mutant strains were then compared for metabolic phenotypic changes using Biolog phenotype microarrays. The responses of both strains to physiologically relevant stress conditions were assessed using DNA microarrays. Transcriptomic data was then analyzed in the context of cellular metabolic pathways and gene networks. Our results showed that deletion of leuD gene has a global effect on both MAP phenotypic and transcriptome response. At the metabolic level, the mutant strain lost the ability to utilize most of the carbon, nitrogen, sulphur, phosphorus and nutrient supplements as energy source. At the transcriptome level, more than 100 genes were differentially expressed in each of the stress condition tested. Systems level network analysis revealed that the differentially expressed genes were distributed throughout the gene network, thus explaining the global impact of leuD deletion in metabolic phenotype. Further, we find that leuD deletion impacted metabolic pathways associated with fatty acids. We verified this by experimentally estimating the total fatty acid content of both mutant and wildtype. The mutant strain had 30% less fatty acid content when compared to wildtype, thus supporting the results from transcriptional and computational analyses. Our results therefore reveal the intricate connection between the metabolism and virulence in MAP
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