760 research outputs found

    Protocol for a randomised, double-blind, placebo-controlled study of grass allergen immunotherapy tablet for seasonal allergic rhinitis: time course of nasal, cutaneous and immunological outcomes

    No full text
    BACKGROUND: Seasonal Allergic Rhinitis is characterised by inflammation of the nasal mucosa upon exposure to common aeroallergens, affecting up to 20-25 % of the population. For those patients whose symptoms are not controlled by standard medical treatment, allergen specific immunotherapy is a therapeutic alternative. Although several studies have shown changes in immunologic responses as well as long term tolerance following treatment with a sublingual allergy immunotherapy tablet, a detailed time course of the early mechanistic changes of local and systemic T and B cell responses and the effects on B cell repertoire in the nasal mucosa have not been fully examined. METHODS/DESIGN: This is a randomized, double-blind, single-centre, placebo controlled, two arm time course study based in the United Kingdom comparing sublingual allergy immunotherapy tablet (GRAZAX(®), ALK-Abello Horsholm, Denmark) plus standard treatment with placebo plus standard treatment. Up to 50 moderate to severe grass pollen allergic participants will be enrolled to ensure randomisation of at least 44. Further, we shall enrol 20 non-atopic volunteers. Screening will be completed before eligible atopic participants are randomised to one of the two treatment arms in a 1 to 1 ratio. The primary endpoint will be the total nasal symptom score assessed over 60 min following grass pollen nasal allergen challenge after 12 months of treatment. Clinical assessments and/or mechanistic analyses on blood, nasal fluid, brushing and biopsies will be performed at baseline at 1, 2, 3, 4 (coinciding with the peak pollen season), 6 and 12 months of treatment. After 12 months of treatment, unblinding will take place. Those atopic participants receiving active treatment will continue therapy for another 12 months followed by a post treatment phase of 12 months. Assessments and collection of biologic samples from these participants will take place again at 24 and at 36 months from the start of treatment. The 20 healthy, non-atopic controls will undergo screening and one visit only coinciding with the 12 month visit for the atopic participants. DISCUSSION: The trial will end in April 2017. The trial is registered with ClinicalTrials.gov and the trial identifying number is NCT02005627. TRIAL REGISTRATION: Primary Registry: ClinicalTrials.gov, Trial Identifying number: NCT02005627, Secondary identifying numbers: EudraCT number: 2013-003732-72 REC: 13/EM/0351, Imperial College London (Sponsor): 13IC0847, Protocol Version 6.0, Date: 16.05.2014

    Discovery of Small-Molecule Enhancers of Reactive Oxygen Species That are Nontoxic or Cause Genotype-Selective Cell Death

    Get PDF
    Elevation of reactive oxygen species (ROS) levels has been observed in many cancer cells relative to nontransformed cells, and recent reports have suggested that small-molecule enhancers of ROS may selectively kill cancer cells in various in vitro and in vivo models. We used a high-throughput screening approach to identify several hundred small-molecule enhancers of ROS in a human osteosarcoma cell line. A minority of these compounds diminished the viability of cancer cell lines, indicating that ROS elevation by small molecules is insufficient to induce death of cancer cell lines. Three chemical probes (BRD5459, BRD56491, BRD9092) are highlighted that most strongly elevate markers of oxidative stress without causing cell death and may be of use in a variety of cellular settings. For example, combining nontoxic ROS-enhancing probes with nontoxic doses of l-buthionine sulfoximine, an inhibitor of glutathione synthesis previously studied in cancer patients, led to potent cell death in more than 20 cases, suggesting that even nontoxic ROS-enhancing treatments may warrant exploration in combination strategies. Additionally, a few ROS-enhancing compounds that contain sites of electrophilicity, including piperlongumine, show selective toxicity for transformed cells over nontransformed cells in an engineered cell-line model of tumorigenesis. These studies suggest that cancer cell lines are more resilient to chemically induced increases in ROS levels than previously thought and highlight electrophilicity as a property that may be more closely associated with cancer-selective cell death than ROS elevation.Chemistry and Chemical Biolog

    Mechanisms of allergen immunotherapy for inhaled allergens and predictive biomarkers

    Get PDF
    Allergen immunotherapy is effective in patients with IgEdependent allergic rhinitis and asthma. When immunotherapy is given continuously for 3 years, there is persistent clinical benefit for several years after its discontinuation. This diseasemodifying effect is both antigen-specific and antigen-driven. Clinical improvement is accompanied by decreases in numbers of effector cells in target organs, including mast cells, basophils, eosinophils, and type 2 innate lymphoid cells. Immunotherapy results in the production of blocking IgG/IgG4 antibodies that can inhibit IgE-dependent activation mediated through both high-affinity IgE receptors (FcεRI) on mast cells and basophils and low-affinity IgE receptors (FcεRII) on B cells. Suppression of TH2 immunity can occur as a consequence of either deletion or anergy of antigen-specific T cells; induction of antigenspecific regulatory T cells; or immune deviation in favor of TH1 responses. It is not clear whether the altered long-term memory resides within the T-cell or the B-cell compartment. Recent data highlight the role of IL-10–producing regulatory B cells and ‘‘protective’’ antibodies that likely contribute to long-term tolerance. Understanding mechanisms underlying induction and persistence of tolerance should identify predictive biomarkers of clinical response and discover novel and more effective strategies for immunotherapy

    Multiplex Cytological Profiling Assay to Measure Diverse Cellular States

    Get PDF
    Computational methods for image-based profiling are under active development, but their success hinges on assays that can capture a wide range of phenotypes. We have developed a multiplex cytological profiling assay that “paints the cell” with as many fluorescent markers as possible without compromising our ability to extract rich, quantitative profiles in high throughput. The assay detects seven major cellular components. In a pilot screen of bioactive compounds, the assay detected a range of cellular phenotypes and it clustered compounds with similar annotated protein targets or chemical structure based on cytological profiles. The results demonstrate that the assay captures subtle patterns in the combination of morphological labels, thereby detecting the effects of chemical compounds even though their targets are not stained directly. This image-based assay provides an unbiased approach to characterize compound- and disease-associated cell states to support future probe discovery

    High-throughput identification of genotype-specific cancer vulnerabilities in mixtures of barcoded tumor cell lines.

    Get PDF
    Hundreds of genetically characterized cell lines are available for the discovery of genotype-specific cancer vulnerabilities. However, screening large numbers of compounds against large numbers of cell lines is currently impractical, and such experiments are often difficult to control. Here we report a method called PRISM that allows pooled screening of mixtures of cancer cell lines by labeling each cell line with 24-nucleotide barcodes. PRISM revealed the expected patterns of cell killing seen in conventional (unpooled) assays. In a screen of 102 cell lines across 8,400 compounds, PRISM led to the identification of BRD-7880 as a potent and highly specific inhibitor of aurora kinases B and C. Cell line pools also efficiently formed tumors as xenografts, and PRISM recapitulated the expected pattern of erlotinib sensitivity in vivo

    A Small-Molecule Probe of the Histone Methyltransferase G9a Induces Cellular Senescence in Pancreatic Adenocarcinoma

    Get PDF
    Post-translational modifications of histones alter chromatin structure and play key roles in gene expression and specification of cell states. Small molecules that target chromatin-modifying enzymes selectively are useful as probes and have promise as therapeutics, although very few are currently available. G9a (also named euchromatin histone methyltransferase 2 (EHMT2)) catalyzes methylation of lysine 9 on histone H3 (H3K9), a modification linked to aberrant silencing of tumor-suppressor genes, among others. Here, we report the discovery of a novel histone methyltransferase inhibitor, BRD4770. This compound reduced cellular levels of di- and trimethylated H3K9 without inducing apoptosis, induced senescence, and inhibited both anchorage-dependent and -independent proliferation in the pancreatic cancer cell line PANC-1. ATM-pathway activation, caused by either genetic or small-molecule inhibition of G9a, may mediate BRD4770-induced cell senescence. BRD4770 may be a useful tool to study G9a and its role in senescence and cancer cell biology.Chemistry and Chemical Biolog

    Subarachnoid-Pleural Fistula: Applied Anatomy of the Thoracic Spinal Nerve Root

    Get PDF
    Subarachnoid-pleural fistula (SPF) is a rare complication of chest or spine operations for neoplastic disease. Concomitant dural and parietal pleural defects permit flow of cerebrospinal fluid into the pleural cavity or intrapleural air into the subarachnoid space. Dural injury recognized intraoperatively permits immediate repair, but unnoticed damage may cause postoperative pleural effusion, intracranial hypotension, meningitis, or pneumocephalus. We review two cases of SPF following surgical intervention for chest wall metastatic disease to motivate a detailed review of the anatomy of neural, osseous, and ligamentous structures at the intervertebral foramen. We further provide recommendations for avoidance and detection of such complication

    Buttressing staples with cholecyst-derived extracellular matrix (CEM) reinforces staple lines in an ex vivo peristaltic inflation model

    Get PDF
    This is the author's accepted manuscript. The final published article is available from the link below. Copyright @ Springer Science + Business Media, LLC 2008Background - Staple line leakage and bleeding are the most common problems associated with the use of surgical staplers for gastrointestinal resection and anastomotic procedures. These complications can be reduced by reinforcing the staple lines with buttressing materials. The current study reports the potential use of cholecyst-derived extracellular matrix (CEM) in non-crosslinked (NCEM) and crosslinked (XCEM) forms, and compares their mechanical performance with clinically available buttress materials [small intestinal submucosa (SIS) and bovine pericardium (BP)] in an ex vivo small intestine model. Methods - Three crosslinked CEM variants (XCEM0005, XCEM001, and XCEM0033) with different degree of crosslinking were produced. An ex vivo peristaltic inflation model was established. Porcine small intestine segments were stapled on one end, using buttressed or non-buttressed surgical staplers. The opened, non-stapled ends were connected to a peristaltic pump and pressure transducer and sealed. The staple lines were then exposed to increased intraluminal pressure in a peristaltic manner. Both the leak and burst pressures of the test specimens were recorded. Results - The leak pressures observed for non-crosslinked NCEM (137.8 ± 22.3 mmHg), crosslinked XCEM0005 (109.1 ± 14.1 mmHg), XCEM001 (150.1 ± 16.0 mmHg), XCEM0033 (98.8 ± 10.5 mmHg) reinforced staple lines were significantly higher when compared to non-buttressed control (28.3 ± 10.8 mmHg) and SIS (one and four layers) (62.6 ± 11.8 and 57.6 ± 12.3 mmHg, respectively) buttressed staple lines. NCEM and XCEM were comparable to that observed for BP buttressed staple lines (138.8 ± 3.6 mmHg). Only specimens with reinforced staple lines were able to achieve high intraluminal pressures (ruptured at the intestinal mesentery), indicating that buttress reinforcements were able to withstand pressure higher than that of natural tissue (physiological failure). Conclusions - These findings suggest that the use of CEM and XCEM as buttressing materials is associated with reinforced staple lines and increased leak pressures when compared to non-buttressed staple lines. CEM and XCEM were found to perform comparably with clinically available buttress materials in this ex vivo model.Enterprise Irelan

    Allergen immunotherapy for asthma prevention: A systematic review and meta-analysis of randomized and non-randomized controlled studies

    Get PDF
    Background: Allergen immunotherapy (AIT) is a disease-modifying treatment for IgE-mediated diseases. Randomized controlled trials (RCTs) support AIT's potential role in asthma prevention but evidence from non-randomized studies of interventions (NRSI) and longitudinal observational studies has been poorly addressed. Therefore, we aimed to conduct a systematic review and meta-analysis to assess clinical data from all study types to evaluate quantitatively the preventive role of AIT in asthma onset. Methods: We search three databases. Studies were screened, selected and evaluated for quality using risk-of-bias (ROB) tools. Data were descriptively summarized and meta-analysed using random effects. We performed a sensitivity, influence and subgroup analyses. Publication bias and heterogeneity were assessed. Results: From the 4549 identified studies, 24 (12 RCTs and 12 NRSI) were included in the qualitative synthesis and 18 underwent meta-analysis. One study was at low ROB, seven had moderate ROB, and 15 were proven of high ROB. Random-effects analysis showed a significant decrease in the risk of developing asthma following AIT by 25% (RR, 95% CI: 0.75, 0.64–0.88). This effect was not significant in the sensitivity analysis. Publication bias raised concerns, together with the moderate heterogeneity between studies (I2 = 58%). Subgroup analysis showed a remarkable preventive effect of AIT in children (RR, 95% CI: 0.71, 0.53–0.96), when completing 3 years of therapy (RR, 95% CI: 0.64, 0.47–0.88), and in mono-sensitized patients (RR, 95% CI: 0.49, 0.39–0.61). Conclusions: Our findings support a possible preventive effect of AIT in asthma onset and suggest an enhanced effect when administered in children, mono-sensitized, and for at least 3 years, independently of allergen type. © 2022 European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.Funding text 1: Mariana Farraia is funded by Fundação para a Ciência e Tecnologia through the PhD Grant number SFRH/BD/145168/2019. João Cavaleiro Rufo is funded by Fundação para a Ciência e Tecnologia through the Stimulus for Scientific Employment Individual Support (2020.01350.CEECIND).; Funding text 2: Mariana Farraia is funded by Fundação para a Ciência e Tecnologia through the PhD Grant number SFRH/BD/145168/2019. João Cavaleiro Rufo is funded by Fundação para a Ciência e Tecnologia through the Stimulus for Scientific Employment Individual Support (2020.01350.CEECIND)
    corecore