296 research outputs found

    The carbohydrate-linked phosphorylcholine of the parasitic nematode product ES-62 modulates complement activation

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    Parasitic nematodes manufacture various carbohydratelinked phosphorylcholine (PCh)-containing molecules, including ES-62, a protein with an N-linked glycan terminally substituted with PCh. The PCh component is biologically important because it is required for immunomodulatory effects. We showed that most ES-62 was bound to a single protein, C-reactive protein (CRP), in normal human serum, displaying a calcium-dependent, high-avidity interaction and ability to form large complexes. Unexpectedly, CRP binding to ES-62 failed to efficiently activate complement as far as the C3 convertase stage in comparison with PCh-BSA and PCh-containing Streptococcus pneumoniae cell wall polysaccharide. C1q capture assays demonstrated an ES-62-CRP-C1q interaction in serum. The three ligands all activated C1 and generated C4b to similar extents. However, a C2a active site was not generated following ES-62 binding to CRP, demonstrating that C2 cleavage was far less efficient for ES-62-containing complexes. We proposed that failure of C2 cleavage was due to the flexible nature of carbohydrate-bound PCh and that reduced proximity of the C1 complex was the reason that C2 was poorly cleaved. This was confirmed using synthetic analogues that were similar to ES-62 only in respect of having a flexible PCh. Furthermore, ES-62 was shown to deplete early complement components, such as the rate-limiting C4, following CRP interaction and thereby inhibit classical pathway activation. Thus, flexible PCh-glycan represents a novel mechanism for subversion of complement activation. These data illustrate the importance of the rate-limiting C4/C2 stage of complement activation and reveal a new addition to the repertoire of ES-62 immunomodulatory mechanisms with possible therapeutic applications

    Diagnostic pathways in multiple myeloma and their relationship to end organ damage: an analysis from the Tackling Early Morbidity and Mortality in Myeloma (TEAMM) trial.

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    Multiple myeloma is associated with significant early morbidity and mortality, with considerable end organ damage often present at diagnosis. The Tackling EArly Morbidity and Mortality in Multiple Myeloma (TEAMM) trial was used to evaluate routes to diagnosis in patients with myeloma and the relationship between diagnostic pathways, time to diagnosis and disease severity. A total of 915 participants were included in the study. Fifty-one per cent were diagnosed by direct referral from primary care to haematology; 29% were diagnosed via acute services and 20% were referred via other secondary care specialties. Patients diagnosed via other secondary care specialties had a longer diagnostic interval (median 120 days vs. 59 days) without an increase in features of severe disease, suggesting they had a relatively indolent disease. Marked intrahospital delay suggests possible scope for improvement. A quarter of those diagnosed through acute services reported >30 days from initial hospital consultation to haematology assessment. Participants diagnosed through acute services had poorer performance status (P < 0·0001) and higher burden of end organ damage (P < 0·0001) with no difference in the overall length of diagnostic pathway compared to those diagnosed by direct referral (median 59 days). This suggests that advanced disease in patients presenting through acute services predominantly reflects disease aggression

    Prophylactic levofloxacin to prevent infections in newly diagnosed symptomatic myeloma: the TEAMM RCT.

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    BACKGROUND: Myeloma causes profound immunodeficiency and recurrent serious infections. There are approximately 5500 new UK cases of myeloma per annum, and one-quarter of patients will have a serious infection within 3 months of diagnosis. Newly diagnosed patients may benefit from antibiotic prophylaxis to prevent infection. However, the use of prophylaxis has not been established in myeloma and may be associated with health-care-associated infections (HCAIs), such as Clostridium difficile. There is a need to assess the benefits and cost-effectiveness of the use of antibacterial prophylaxis against any risks in a double-blind, placebo-controlled, randomised clinical trial. OBJECTIVES: To assess the risks, benefits and cost-effectiveness of prophylactic levofloxacin in newly diagnosed symptomatic myeloma patients. DESIGN: Multicentre, randomised, double-blind, placebo-controlled trial. A central telephone randomisation service used a minimisation computer algorithm to allocate treatments in a 1 : 1 ratio. SETTING: A total of 93 NHS hospitals throughout England, Northern Ireland and Wales. PARTICIPANTS: A total of 977 patients with newly diagnosed symptomatic myeloma. INTERVENTION: Patients were randomised to receive levofloxacin or placebo tablets for 12 weeks at the start of antimyeloma treatment. Treatment allocation was blinded and balanced by centre, estimated glomerular filtration rate and intention to give high-dose chemotherapy with autologous stem cell transplantation. Follow-up was at 4-week intervals up to 16 weeks, with a further follow-up at 1 year. MAIN OUTCOME MEASURES: The primary outcome was to assess the number of febrile episodes (or deaths) in the first 12 weeks from randomisation. Secondary outcomes included number of deaths and infection-related deaths, days in hospital, carriage and invasive infections, response to antimyeloma treatment and its relation to infection, quality of life and overall survival within the first 12 weeks and beyond. RESULTS: In total, 977 patients were randomised (levofloxacin, n = 489; placebo, n = 488). A total of 134 (27%) events (febrile episodes, n = 119; deaths, n = 15) occurred in the placebo arm and 95 (19%) events (febrile episodes, n = 91; deaths, n = 4) occurred in the levofloxacin arm; the hazard ratio for time to first event (febrile episode or death) within the first 12 weeks was 0.66 (95% confidence interval 0.51 to 0.86; p = 0.002). Levofloxacin also reduced other infections (144 infections from 116 patients) compared with placebo (179 infections from 133 patients; p-trend of 0.06). There was no difference in new acquisitions of C. difficile, methicillin-resistant Staphylococcus aureus and extended-spectrum beta-lactamase Gram-negative organisms when assessed up to 16 weeks. Levofloxacin produced slightly higher quality-adjusted life-year gains over 16 weeks, but had associated higher costs for health resource use. With a median follow-up of 52 weeks, there was no significant difference in overall survival (p = 0.94). LIMITATIONS: Short duration of prophylactic antibiotics and cost-effectiveness. CONCLUSIONS: During the 12 weeks from new diagnosis, the addition of prophylactic levofloxacin to active myeloma treatment significantly reduced febrile episodes and deaths without increasing HCAIs or carriage. Future work should aim to establish the optimal duration of antibiotic prophylaxis and should involve the laboratory investigation of immunity, inflammation and disease activity on stored samples funded by the TEAMM (Tackling Early Morbidity and Mortality in Myeloma) National Institute for Health Research Efficacy and Mechanism Evaluation grant (reference number 14/24/04). TRIAL REGISTRATION: Current Controlled Trials ISRCTN51731976. FUNDING DETAILS: This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 62. See the NIHR Journals Library website for further project information

    C-reactive protein is essential for innate resistance to pneumococcal infection

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    Summary: No deficiency of human C-reactive protein (CRP), or even structural polymorphism of the protein, has yet been reported so its physiological role is not known. Here we show for the first time that CRP-deficient mice are remarkably susceptible to Streptococcus pneumoniae infection and are protected by reconstitution with isolated pure human CRP, or by anti-pneumococcal antibodies. Autologous mouse CRP is evidently essential for innate resistance to pneumococcal infection before antibodies are produced. Our findings are consistent with the significant association between clinical pneumococcal infection and non-coding human CRP gene polymorphisms which affect CRP expression. Deficiency or loss of function variation in CRP may therefore be lethal at the first early-life encounter with this ubiquitous virulent pathogen, explaining the invariant presence and structure of CRP in human adults

    Friendship activities of adults with intellectual disability in supported accommodation in northern England

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    Background Despite there being considerable evidence to suggest that friendships are central to health and well-being, relatively little attention had been paid to the friendships of people with intellectual disabilities. Methods Friendship activities involving people with and without intellectual disabilities were measured over the preceding month in a sample of 1542 adults with intellectual disabilities receiving supported accommodation in nine geographical localities in Northern England. Results The results of the study indicate: (1) low levels of friendship activities among people with intellectual disabilities in supported accommodation; (2) people with intellectual disabilities are more likely to be involved in activities with friends who also have intel lectual disabilities than with friends who do not have intellectual disabilities; (3) most friendship activities take place in the public domain rather than in more private settings (e.g. at home); (4) the setting in which a person lives is a more significant determinant of the form and content of activities with their friends than the characteristics of participants. Conclusions Further attention needs to be given to research and practice initiatives aimed at increasing the levels of friendship activities of people with intellectual disabilities

    Stratifying risk of infection and response to therapy in patients with myeloma: a prognostic study

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    Background Multiple myeloma is a cancer of plasma cells that is associated with severe immunodeficiency and increased numbers of bacterial infections. The Tackling Early Morbidity and Mortality in Myeloma (TEAMM) trial assessed the use of prophylactic levofloxacin in newly diagnosed multiple myeloma patients. Interactions between multiple myeloma disease activity, immunity and infection are central to the TEAMM trial. Active multiple myeloma suppresses immunity and infections delay administration of anti-multiple myeloma therapy. Furthermore, infection-derived inflammation nurtures multiple myeloma activity and resistance to anti-multiple myeloma therapy. Objectives The aim of this study was to measure biomarkers of (1) immune competence to develop risk stratification of patients for infection to personalise the decision to prescribe antibiotics, (2) myeloma activity to sensitively measure speed and depth of myeloma response and (3) inflammation to identify patients who may be at risk of poor treatment responses. Method Serum samples were collected from 977 TEAMM trial patients (aged 35–90 years) at randomisation, then every 4 weeks for 16 weeks and again at 1 year. Biomarker levels were compared with samples from healthy controls. Multiplex Luminex® assays (R&D Systems, Minneapolis, MN, USA) and enzyme-linked immunosorbent assays were used for the analysis of biomarkers and anti-viral antibodies were measured by a haemagglutination assay. Results At baseline, levels of both polyclonal immunoglobulins and anti-bacterial antibodies were below the normal range in most TEAMM trial patients. This immunoparesis was much more severe for antibodies against specific bacterial targets than for total immunoglobulin levels. Levels of anti-bacterial antibodies were below the threshold of protection for 18 of the 19 bacterial antigens tested. More patients aged < 65 years were protected against meningococcal serotypes, Haemophilus influenza type b and tetanus, whereas more patients aged ≥ 65 years were protected against pneumococcal serotypes but there was good protection in only 6% of the TEAMM trial patients. Higher levels of polyclonal immunoglobulins, but not specific anti-bacterial antibodies, were found to be associated with a lower risk of infection and a longer survival. At presentation, levels of neutrophil elastase, calprotectin and interleukin 10 were elevated in TEAMM trial patients, compared with healthy controls. Interleukin 10 levels were related to infection during the trial: patients with interleukin 10 levels ≥ 10 pg/ml had a greater risk of infection than patients with interleukin 10 levels < 10 pg/ml. Levels of soluble CD138 were elevated in 72% of TEAMM trial patients and were decreased in response to therapy, with a complete response seen in 40% of TEAMM trial patients by 16 weeks. Of the 76 TEAMM trial patients achieving a free light chain complete response at 16 weeks, only 30% had a soluble CD138 complete response. Overall, responses in the levels of soluble CD138 did not correlate with free light chain and myeloma monoclonal protein (also known as m-protein) responses, consistent with the fact that soluble CD138 responses reflect a separate aspect of disease activity and clonal size. Levels of procalcitonin were elevated in only 50% of patients who had febrile episodes during the TEAMM trial. Although levels of interleukins 6 and 8 at presentation were lower than in a heathy cohort of patients, lower levels of interleukin 6 were identified at baseline in poor responders than in good responders, and in patients who had febrile and non-febrile infections during the trial than in patients who had only non-febrile episodes. Conclusion Information from this Efficacy and Mechanism Evaluation project can help inform risk stratification and patient identification strategies to be responsive to individual patient needs. Monitoring levels of free light chains and soluble CD138 can help identify non-responders early and monitoring interleukin 10 levels can help stratify patients for risk of infection. Furthermore, immunisation in remission should be tested. Limitations The TEAMM trial administered prophylactic antibiotics or placebo for 12 weeks from a new diagnosis of myeloma. Patients were monitored for infections for 16 weeks post diagnosis, with a final set of clinical data gathered at 1 year. Infection data and efficacy of prophylactic antibiotics are available for only the first 16 weeks and survival for the first 52 weeks. This limits long-term data, particularly for progression-free and overall survival. Future work The TEAMM 2 trial (in preparation) will explore the benefit of prophylactic antibiotics up to 12 months following diagnosis and will explore infection risk post therapy and during remission. Furthermore, some of the key findings will be applied to investigate biomarkers in samples from other UK myeloma trials in which long-term outcome data are available. Trial registration Current Controlled Trials ISRCTN51731976. Funding This project was funded by the Efficacy and Mechanism Evaluation programme, a Medical Research Council and National Institute for Health Research (NIHR) partnership, and will be published in full in Efficacy and Mechanism Evaluation; Vol. 7, No. 10. See the NIHR Journals Library website for further project information

    Genetic, environmental and stochastic factors in monozygotic twin discordance with a focus on epigenetic differences

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    PMCID: PMC3566971This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited

    Small Heat Shock Proteins Potentiate Amyloid Dissolution by Protein Disaggregases from Yeast and Humans

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    The authors define how small heat-shock proteins synergize to regulate the assembly and disassembly of a beneficial prion, and then they exploit this knowledge to identify the human amyloid depolymerase
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