Failure of Interferon γ to Induce the Anti-Inflammatory Interleukin 18 Binding Protein in Familial Hemophagocytosis

Background: Familial hemophagocytosis (FHL) is a rare disease associated with defects in proteins involved in CD8+ T-cell cytotoxicity. Hyperactivation of immune cells results in a perilous, Th1-driven cytokine storm. We set out to explore the regulation of cytokines in an FHL patient who was clinically stable on low-dose immunosuppressive therapy after bone marrow transplantation over a six-month period. During this period, chimerism analyses showed that the fraction of host cells was between 1 and 10%. Both parents of the patient as well as healthy volunteers were studied for comparison. Methods/Principal Findings: Using ELISA, quantitative real-time PCR, and clinical laboratory methods, we investigated constitutive and inducible cytokines, polymorphisms, and clinical parameters in whole blood and whole blood cultures. Although routine laboratory tests were within the normal range, the chemokines IP-10 and IL-8 as well as the cytokine IL-27p28 were increased up to 10-fold under constitutive and stimulated conditions compared to healthy controls. Moreover, high levels of IFNgamma and TNFalpha were produced upon stimulation. Unexpectedly, IFNgamma induction of IL-18 binding protein (IL-18BP) was markedly reduced (1.6-fold vs 5-fold in controls). The patient's mother featured intermediately increased cytokine levels, whereas levels in the father were similar to those in the controls. Conclusions/Significance: Since IL-18 plays a major role in perpetuating hemophagocytosis, the failure of IFNgamma to induce IL-18BP may constitute a fundamental pathogenetic mechanism. Furthermore, increased production of IL-8 and IL-27 appears to be associated with this disease. Such dysregulation of cytokines was also found in the heterozygous parents, providing a novel insight into genotype-phenotype correlation of FHL which may encourage future research of this rare disease

IL-27 Regulates IL-18 Binding Protein in Skin Resident Cells

IL-18 is an important mediator involved in chronic inflammatory conditions such as cutaneous lupus erythematosus, psoriasis and chronic eczema. An imbalance between IL-18 and its endogenous antagonist IL-18 binding protein (BP) may account for increased IL-18 activity. IL-27 is a cytokine with dual function displaying pro- and anti-inflammatory properties. Here we provide evidence for a yet not described anti-inflammatory mode of action on skin resident cells. Human keratinocytes and surprisingly also fibroblasts (which do not produce any IL-18) show a robust, dose-dependent and highly inducible mRNA expression and secretion of IL-18BP upon IL-27 stimulation. Other IL-12 family members failed to induce IL-18BP. The production of IL-18BP peaked between 48–72 h after stimulation and was sustained for up to 96 h. Investigation of the signalling pathway showed that IL-27 activates STAT1 in human keratinocytes and that a proximal GAS site at the IL-18BP promoter is of importance for the functional activity of IL-27. The data are in support of a significant anti-inflammatory effect of IL-27 on skin resident cells. An important novel property of IL-27 in skin pathobiology may be to counter-regulate IL-18 activities by acting on keratinocytes and importantly also on dermal fibroblasts

Alignment of the CMS tracker with LHC and cosmic ray data

© CERN 2014 for the benefit of the CMS collaboration, published under the terms of the Creative Commons Attribution 3.0 License by IOP Publishing Ltd and Sissa Medialab srl. Any further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation and DOI.The central component of the CMS detector is the largest silicon tracker ever built. The precise alignment of this complex device is a formidable challenge, and only achievable with a significant extension of the technologies routinely used for tracking detectors in the past. This article describes the full-scale alignment procedure as it is used during LHC operations. Among the specific features of the method are the simultaneous determination of up to 200 000 alignment parameters with tracks, the measurement of individual sensor curvature parameters, the control of systematic misalignment effects, and the implementation of the whole procedure in a multi-processor environment for high execution speed. Overall, the achieved statistical accuracy on the module alignment is found to be significantly better than 10μm

Excessive cytokine production in WB cultures from the FHL patient.

<p>WB culture were incubated for 20 h; thereafter, ELISA was performed on lysates (IL-8) or supernatants (others). Data are shown as cytokine protein in pg normalized to 1 million white blood cells ± SEM, n = 4 time points for IP-10 and IL-8 and n = 3 for IFNγ and TNFα spanning 6 months for all subjects; the same three healthy donors were tested on each time point. *, p<0.05 and **, p<0.01 for healthy controls vs patient, mother, and father; #, p<0.05 and ##, p<0.01 for patient vs mother and father.</p

Regulation of IL-18BP and IL-27p28.

<p>RNA was isolated from WB culture after a 20 h incubation with or without 50 ng/ml IFNγ. <b>A,</b> Data are shown as absolute copy numbers of IL-18BP normalized to GAPDH×10³± SEM, n = 4 time points for all subjects; three control individuals were assayed on each time point. <b>B,</b> IFNγ-induced fold-changes in normalized IL-18BP mRNA copy numbers are shown. <b>A</b> and <b>B,</b> *, p<0.05 and **, p<0.01 for healthy donors vs patient, mother, and father; #, p<0.05 for patient vs mother and father. <b>C,</b> IL-27p28 PCR from the same samples. Differences in GAPDH copy numbers were negligible. One representative of 3 different gels showing similar results is depicted. Healthy donor C exhibited no expression of IL-27p28 (not shown).</p

Cytokine levels in WB cultures stimulated with LPS.

<p>WB cultures were incubated in the presence of 100 ng/ml LPS for 20 h. In panel <b>D</b>, IL-12 (20 ng/ml) was also added. IL-8 was measured in cell lysates, IP-10, TNFα, and IFNγ were determined in the supernatants. Data are depicted as cytokine protein in pg normalized to 1 million white blood cells ± SEM, n = 4 time points for IP-10 and IL-8 and n = 3 for IFNγ and TNFα over a period of 6 months for all subjects; the identical healthy volunteers were tested on each time point. *, p<0.05 and **, p<0.01 for healthy controls vs patient, mother, and father; #, p<0.05 and ##, p<0.01 for patient vs mother and father.</p

Description and performance of track and primary-vertex reconstruction with the CMS tracker

A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tbar t events under typical 2011 pileup conditions, the average track-reconstruction efficiency for promptly-produced charged particles with transverse momenta of p(T) > 0.9GeV is 94% for pseudorapidities of |η| < 0.9 and 85% for 0.9 < |η| < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p(T) = 100GeV emitted at |η| < 1.4, the resolutions are approximately 2.8% in p(T), and respectively, 10μm and 30μm in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10–12μm in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung