13 research outputs found

    In Vivo Inflammation Does Not Impair ABCA1-Mediated Cholesterol Efflux Capacity of HDL

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    HDL provides atheroprotection by facilitating cholesterol efflex from lipid-laden macrophages in the vessel wall. In vitro studies have suggested impaired efflux capacity of HDL following inflammatory changes. We assessed the impact of acute severe sepsis and mild chronic inflammatory disease on the efflux capacity of HDL. We hypothesize that a more severe inflammatory state leads to stronger impaired cholesterol efflux capacity. Using lipid-laden THP1 cells and fibroblasts we were able to show that efflux capacity of HDL from both patients with severe sepsis or with Crohn's disease (active or in remission), either isolated using density gradient ultracentrifugation or using apoB precipitation, was not impaired. Yet plasma levels of HDL cholesterol and apoA-I were markedly lower in patients with sepsis. Based on the current observations we conclude that inflammatory disease does not interfere with the capacity of HDL to mediate cholesterol efflux. Our findings do not lend support to the biological relevance of HDL function changes in vitro

    Genetic deficiency of NOD2 confers resistance to invasive aspergillosis

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    Invasive aspergillosis (IA) is a severe infection that can occur in severely immunocompromised patients. Efficient immune recognition of Aspergillus is crucial to protect against infection, and previous studies suggested a role for NOD2 in this process. However, thorough investigation of the impact of NOD2 on susceptibility to aspergillosis is lacking. Common genetic variations in NOD2 has been associated with Crohn's disease and here we investigated the influence of these  genetic variations on the anti-Aspergillus host response. A NOD2 polymorphism reduced the risk of IA after hematopoietic stem-cell transplantation. Mechanistically, absence of NOD2 in monocytes and macrophages increases phagocytosis leading to enhanced fungal killing, conversely, NOD2 activation reduces the antifungal potential of these cells. Crucially, Nod2 deficiency results in resistance to Aspergillus infection in an in vivo model of pulmonary aspergillosis. Collectively, our data demonstrate that genetic deficiency of NOD2 plays a protective role during Aspergillus infection.We thank C. Wertz and M. Fanton D'Andon for providing Nod2-deficient mice, M. Schlotter for organizing patient inclusion, B. Rosler for assistance with flowcytometry. We also thank the NOD2-deficient patients for contributing to our study by providing blood samples. M.S.G. was supported by the Erasmus lifelong learning program. F.L.v.d.V. was supported by the E-rare project EURO-CMC. M.O. was supported by the NWO, 016.176.006). A.C. and C.C. were supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (FEDER) (NORTE-01-0145-FEDER-000013), and the Fundacao para a Ciencia e Tecnologia (FCT) (IF/00735/2014 to A.C. and SFRH/BPD/96176/2013 to C. C.)

    Inflammatory bowel disease. Correlating the genotype to the clinical and immunological phenotype

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    De ziekte van Crohn en colitis ulcerosa zijn chronische inflammatoire darmziekten (IBD). Deze aandoeningen hebben een complexe genetische en auto-immunologische basis waarover nog steeds weinig bekend is. Simone Wolfkamp onderzocht de genetische aanleg bij verschillende IBD-patiënten in combinatie met de immunologische reactie in hun bloed. Tevens keek ze naar nieuwe genetische risicovarianten voor inflammatoire darmziekten. Bij de studies naar de immunologische reacties koppelde Wolfkamp bekende genetische risicovarianten aan klinische en immunologische fenotypen van IBD-patiënten. Deze risicovarianten werden gevonden in twee belangrijke cellulaire routes

    Hypnotherapy for children with functional abdominal pain or irritable bowel syndrome: a randomized controlled trial

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    BACKGROUND & AIMS: Functional abdominal pain (FAP) and irritable bowel syndrome (IBS) are highly prevalent in childhood. A substantial proportion of patients continues to experience long-lasting symptoms. Gut-directed hypnotherapy (HT) has been shown to be highly effective in the treatment of adult IBS patients. We undertook a randomized controlled trial and compared clinical effectiveness of HT with standard medical therapy (SMT) in children with FAP or IBS. METHODS: Fifty-three pediatric patients, age 8-18 years, with FAP (n = 31) or IBS (n = 22), were randomized to either HT or SMT. Hypnotherapy consisted of 6 sessions over a 3-month period. Patients in the SMT group received standard medical care and 6 sessions of supportive therapy. Pain intensity, pain frequency, and associated symptoms were scored in weekly standardized abdominal pain diaries at baseline, during therapy, and 6 and 12 months after therapy. RESULTS: Pain scores decreased significantly in both groups: from baseline to 1 year follow-up, pain intensity scores decreased in the HT group from 13.5 to 1.3 and in the SMT group from 14.1 to 8.0. Pain frequency scores decreased from 13.5 to 1.1 in the HT group and from 14.4 to 9.3 in the SMT group. Hypnotherapy was highly superior, with a significantly greater reduction in pain scores compared with SMT (P < .001). At 1 year follow-up, successful treatment was accomplished in 85% of the HT group and 25% of the SMT group (P < .001). CONCLUSIONS: Gut-directed HT is highly effective in the treatment of children with longstanding FAP or IB

    Confirmation of Multiple Crohn's Disease Susceptibility Loci in a Large Dutch-Belgian Cohort

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    OBJECTIVES: Inflammatory bowel diseases (IBD)-Crohn's disease (CD) and ulcerative colitis (UC)-are chronic gastrointestinal inflammatory disorders with a complex genetic background. A genome-wide association scan by the Wellcome Trust Case Control Consortium (WTCCC) recently identified several novel susceptibility loci. METHODS: We performed a large replication study in 2,731 Dutch and Belgian IBD patients (1,656 CD and 1,075 UC) and 1,086 controls. In total, 40 single nucleotide polymorphisms (SNPs) that showed moderate or strong association in the WTCCC study, along with SNPs in the previously identified genes IL23R, ATG16L1, and NELL1, were studied. RESULTS: We confirmed the associations with IL23R (rs11209026, P=2.69E-12), ATG16L1 (rs2241880, P=4.82E-07), IRGM (rs4958847, P=2.26E-05), NKX2-3 (rs10883365, P=5.91E-06), 1q24 (rs12035082, P=1.51E-05), 5p13 (rs17234657, P=2.62E-05), and 10q21 (rs10761659, P=8.95E-04). We also identified associations with cyclin Y(CCNY; rs3936503, P=2.09 E-04) and Hect domain and RCC1-like domain 2 (HERC2; rs916977, P=1.12E- 04). Pooling our data with the original WTCCC data substantiated these associations. Several SNPs were also moderately associated with UC. Two genetic risk profiles based on the number of risk alleles and based on a weighted score were created. On the basis of these results, we calculated sensitivities, specificities, positive and negative predictive values, and likelihood ratios for CD. CONCLUSIONS: We replicated genetic associations for CD with IL23R, ATG16L1, IRGM, NKX2-3, 1q24, 10q21, 5p13, and PTPN2 and report evidence for associations with HERC2 and CCNY. Pooling our data with the results of the WTCCC strengthened the results, suggesting genuine genetic associations. We show that a genetic risk profile can be constructed that is clinically useful and that can aid in making treatment decisions

    Autophagy Attenuates the Adaptive Immune Response by Destabilizing the Immunologic Synapse

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    BACKGROUND & AIMS: Variants in the genes ATG16L1 and IRGM affect autophagy and are associated with the development of Crohn's disease. It is not clear how autophagy is linked to loss of immune tolerance in the intestine. We investigated the involvement of the immunologic synapse-the site of contact between dendritic cells (DCs) and T cells, which contains molecules involved in antigen recognition and regulates immune response. METHODS: DC autophagy was reduced using small interfering RNAs or pharmacologic inhibitors. DC phenotype and function were analyzed by confocal microscopy, time-lapse microscopy, and flow cytometry. We also examined DCs isolated from patients with Crohn's disease who carried the ATG16L1 risk allele. RESULTS: Immunologic synapse formation induced formation of autophagosomes in DCs; the autophagosomes were oriented toward the immunologic synapse and contained synaptic components. Knockdown of ATG16L1 and IRGM with small interfering RNAs in DCs resulted in hyperstable interactions between DCs and T cells, increased activation of T cells, and activation of a T-helper 17 cell response. LKB1 was recruited to the immunologic synapse, and induction of autophagy in DC required inhibition of mammalian target of rapamycine signaling by the LKB1-AMP activated protein kinase (AMPK) pathway. DCs from patients with Crohn's disease who had an ATG16L1 risk allele had a similar hyperstability of the immunologic synapse. CONCLUSIONS: Autophagy is induced upon formation of the immunologic synapse and negatively regulates T-cell activation. This mechanism might increase adaptive immunity in patients with Crohn's disease who carry ATG16L1 risk allele

    Confirmation of Multiple Crohn's Disease Susceptibility Loci in a Large Dutch-Belgian Cohort

    No full text
    Inflammatory bowel diseases (IBD)-Crohn's disease (CD) and ulcerative colitis (UC)-are chronic gastrointestinal inflammatory disorders with a complex genetic background. A genome-wide association scan by the Wellcome Trust Case Control Consortium (WTCCC) recently identified several novel susceptibility loci. We performed a large replication study in 2,731 Dutch and Belgian IBD patients (1,656 CD and 1,075 UC) and 1,086 controls. In total, 40 single nucleotide polymorphisms (SNPs) that showed moderate or strong association in the WTCCC study, along with SNPs in the previously identified genes IL23R, ATG16L1, and NELL1, were studied. We confirmed the associations with IL23R (rs11209026, P=2.69E-12), ATG16L1 (rs2241880, P=4.82E-07), IRGM (rs4958847, P=2.26E-05), NKX2-3 (rs10883365, P=5.91E-06), 1q24 (rs12035082, P=1.51E-05), 5p13 (rs17234657, P=2.62E-05), and 10q21 (rs10761659, P=8.95E-04). We also identified associations with cyclin Y (CCNY; rs3936503, P=2.09 E-04) and Hect domain and RCC1-like domain 2 (HERC2; rs916977, P=1.12E-04). Pooling our data with the original WTCCC data substantiated these associations. Several SNPs were also moderately associated with UC. Two genetic risk profiles based on the number of risk alleles and based on a weighted score were created. On the basis of these results, we calculated sensitivities, specificities, positive and negative predictive values, and likelihood ratios for CD. We replicated genetic associations for CD with IL23R, ATG16L1, IRGM, NKX2-3, 1q24, 10q21, 5p13, and PTPN2 and report evidence for associations with HERC2 and CCNY. Pooling our data with the results of the WTCCC strengthened the results, suggesting genuine genetic associations. We show that a genetic risk profile can be constructed that is clinically useful and that can aid in making treatment decision
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