115 research outputs found

    IgG 3 + B cells are associated with the development of multiple sclerosis

    Get PDF
    Objectives Disease‐modifying therapies (DMTs) targeting B cells are amongst the most effective for preventing multiple sclerosis (MS) progression. IgG3 antibodies and their uncharacterised B‐cell clones are predicted to play a pathogenic role in MS. Identifying subsets of IgG3+ B cells involved in MS progression could improve diagnosis, could inform timely disease intervention and may lead to new DMTs that target B cells more specifically. Methods We designed a 31‐parameter B‐cell‐focused mass cytometry panel to interrogate the role of peripheral blood IgG3+ B cells in MS progression of two different patient cohorts: one to investigate the B‐cell subsets involved in conversion from clinically isolated syndrome (CIS) to MS; and another to compare MS patients with inactive or active stages of disease. Each independent cohort included a group of non‐MS controls. Results Nine distinct CD20+IgD−IgG3+ B‐cell subsets were identified. Significant changes in the proportion of CD21+CD24+CD27−CD38− and CD27+CD38hiCD71hi memory B‐cell subsets correlated with changes in serum IgG3 levels and time to conversion from CIS to MS. The same CD38− double‐negative B‐cell subset was significantly elevated in MS patients with active forms of the disease. A third CD21+CD24+CD27+CD38− subset was elevated in patients with active MS, whilst narrowband UVB significantly reduced the proportion of this switched‐memory B‐cell subset. Conclusion We have identified previously uncharacterised subsets of IgG3+ B cells and shown them to correlate with autoimmune attacks on the central nervous system (CNS). These results highlight the potential for therapies that specifically target IgG3+ B cells to impact MS progression

    Pellino-1 regulates the responses of the airway to viral infection

    Get PDF
    Exposure to respiratory pathogens is a leading cause of exacerbations of airway diseases such as asthma and chronic obstructive pulmonary disease (COPD). Pellino-1 is an E3 ubiquitin ligase known to regulate virally-induced inflammation. We wished to determine the role of Pellino-1 in the host response to respiratory viruses in health and disease. Pellino-1 expression was examined in bronchial sections from patients with GOLD stage two COPD and healthy controls. Primary bronchial epithelial cells (PBECs) in which Pellino-1 expression had been knocked down were extracellularly challenged with the TLR3 agonist poly(I:C). C57BL/6 Peli1−/− mice and wild type littermates were subjected to intranasal infection with clinically-relevant respiratory viruses: rhinovirus (RV1B) and influenza A. We found that Pellino-1 is expressed in the airways of normal subjects and those with COPD, and that Pellino-1 regulates TLR3 signaling and responses to airways viruses. In particular we observed that knockout of Pellino-1 in the murine lung resulted in increased production of proinflammatory cytokines IL-6 and TNFα upon viral infection, accompanied by enhanced recruitment of immune cells to the airways, without any change in viral replication. Pellino-1 therefore regulates inflammatory airway responses without altering replication of respiratory viruses

    The ZEPLIN-III dark matter detector: performance study using an end-to-end simulation tool

    Get PDF
    We present results from a GEANT4-based Monte Carlo tool for end-to-end simulations of the ZEPLIN-III dark matter experiment. ZEPLIN-III is a two-phase detector which measures both the scintillation light and the ionisation charge generated in liquid xenon by interacting particles and radiation. The software models the instrument response to radioactive backgrounds and calibration sources, including the generation, ray-tracing and detection of the primary and secondary scintillations in liquid and gaseous xenon, and subsequent processing by data acquisition electronics. A flexible user interface allows easy modification of detector parameters at run time. Realistic datasets can be produced to help with data analysis, an example of which is the position reconstruction algorithm developed from simulated data. We present a range of simulation results confirming the original design sensitivity of a few times 10−810^{-8} pb to the WIMP-nucleon cross-section.Comment: Submitted to Astroparticle Physic

    Bio-analytical Assay Methods used in Therapeutic Drug Monitoring of Antiretroviral Drugs-A Review

    Get PDF

    Measurement of the muon flux from 400 GeV/c protons interacting in a thick molybdenum/tungsten target

    Get PDF
    The SHiP experiment is proposed to search for very weakly interacting particles beyond the Standard Model which are produced in a 400 GeV/c proton beam dump at the CERN SPS. About 1011 muons per spill will be produced in the dump. To design the experiment such that the muon-induced background is minimized, a precise knowledge of the muon spectrum is required. To validate the muon flux generated by our Pythia and GEANT4 based Monte Carlo simulation (FairShip), we have measured the muon flux emanating from a SHiP-like target at the SPS. This target, consisting of 13 interaction lengths of slabs of molybdenum and tungsten, followed by a 2.4 m iron hadron absorber was placed in the H4 400 GeV/c proton beam line. To identify muons and to measure the momentum spectrum, a spectrometer instrumented with drift tubes and a muon tagger were used. During a 3-week period a dataset for analysis corresponding to (3.27±0.07) × 1011 protons on target was recorded. This amounts to approximatively 1% of a SHiP spill

    Track reconstruction and matching between emulsion and silicon pixel detectors for the SHiP-charm experiment

    Get PDF
    In July 2018 an optimization run for the proposed charm cross section measurement for SHiP was performed at the CERN SPS. A heavy, moving target instrumented with nuclear emulsion films followed by a silicon pixel tracker was installed in front of the Goliath magnet at the H4 proton beam-line. Behind the magnet, scintillating-fibre, drift-tube and RPC detectors were placed. The purpose of this run was to validate the measurement's feasibility, to develop the required analysis tools and fine-tune the detector layout. In this paper, we present the track reconstruction in the pixel tracker and the track matching with the moving emulsion detector. The pixel detector performed as expected and it is shown that, after proper alignment, a vertex matching rate of 87% is achieved

    Determining aluminium co-ordination of kaolinitic clays before and after calcination with electron energy loss spectroscopy

    Get PDF
    Developing a greater understanding of kaolinite dehydroxylation upon calcination is crucial for several industrial applications, including cements. Aluminium coordination in meta-kaolinite indicates the extent of its dehydroxylation and its potential chemical reactivity, and it is typically determined using 27Al magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. This technique however presents limitations for Fe-rich materials, given the magnetic properties of Fe ions and minerals containing Fe. In this study, the effect of calcination on Al coordination was assessed in a low-Fe clay used as a reference system, and a Fe-rich clay. Al coordination in the low-Fe clay was quantified via 27Al MAS NMR spectra deconvolution, using data collected at 9.4 T and 11.7 T. Energy dispersive X-ray spectroscopy (EDX) maps and electron energy loss spectroscopy (EELS) measurements were carried out in a scanning transmission electron microscope (STEM) on both clays. Al K-edge EEL spectra showed distinguishable 4/5-fold Al and 6-fold Al sites in both clay types. Differences in line-profile indicated a higher proportion of 4/5-fold Al in kaolinite in the Fe-rich clay compared to the low-Fe clay. Conversely, the Fe-rich clay contained a lower proportion of 4/5-fold Al in meta-kaolinite after calcination, relative to the low-Fe clay. These differences are consistent with the greater structural disorder of the meta-kaolinite identified in the Fe-rich clay by X-ray diffraction and the geological origins of both clays. Overall, this study demonstrates the potential of EELS to provide information about Al coordination for individual kaolinite and meta-kaolinite particles

    The 1988–89 Taulbee survey report

    No full text
    • 

    corecore