Chromatin Binding of c-REL and p65 Is Not Limiting for Macrophage IL12B Transcription During Immediate Suppression by Ovarian Carcinoma Ascites

Tumors frequently exploit homeostatic mechanisms that suppress expression of IL-12, a central mediator of inflammatory and anti-tumor responses. The p40 subunit of the IL-12 heterodimer, encoded by IL12B, is limiting for these functions. Ovarian carcinoma patients frequently produce ascites which exerts immunosuppression by means of soluble factors. The NFκB pathway is necessary for transcription of IL12B, which is not expressed in macrophages freshly isolated from ascites. This raises the possibility that ascites prevents IL12B expression by perturbing NFκB binding to chromatin. Here, we show that ascites-mediated suppression of IL12B induction by LPS plus IFNγ in primary human macrophages is rapid, and that suppression can be reversible after ascites withdrawal. Nuclear translocation of the NFκB transcription factors c-REL and p65 was strongly reduced by ascites. Surprisingly, however, their binding to the IL12B locus and to CXCL10, a second NFκB target gene, was unaltered, and the induction of CXCL10 transcription was not suppressed by ascites. These findings indicate that, despite its reduced nuclear translocation, NFκB function is not generally impaired by ascites, suggesting that ascites-borne signals target additional pathways to suppress IL12B induction. Consistent with these data, IL-10, a clinically relevant constituent of ascites and negative regulator of NFκB translocation, only partially recapitulated IL12B suppression by ascites. Finally, restoration of a defective IL-12 response by appropriate culture conditions was observed only in macrophages from a subset of donors, which may have important implications for the understanding of patient-specific immune responses

Small intestinal mucosa expression of putative chaperone fls485

<p>Abstract</p> <p>Background</p> <p>Maturation of enterocytes along the small intestinal crypt-villus axis is associated with significant changes in gene expression profiles. <it>fls485 </it>coding a putative chaperone protein has been recently suggested as a gene involved in this process. The aim of the present study was to analyze <it>fls48</it>5 expression in human small intestinal mucosa.</p> <p>Methods</p> <p><it>fls485 </it>expression in purified normal or intestinal mucosa affected with celiac disease was investigated with a molecular approach including qRT-PCR, Western blotting, and expression strategies. Molecular data were corroborated with several <it>in situ </it>techniques and usage of newly synthesized mouse monoclonal antibodies.</p> <p>Results</p> <p>fls485 mRNA expression was preferentially found in enterocytes and chromaffine cells of human intestinal mucosa as well as in several cell lines including Rko, Lovo, and CaCo2 cells. Western blot analysis with our new anti-fls485 antibodies revealed at least two fls485 proteins. In a functional CaCo2 model, an increase in fls485 expression was paralleled by cellular maturation stage. Immunohistochemistry demonstrated fls485 as a cytosolic protein with a slightly increasing expression gradient along the crypt-villus axis which was impaired in celiac disease Marsh IIIa-c.</p> <p>Conclusions</p> <p>Expression and synthesis of fls485 are found in surface lining epithelia of normal human intestinal mucosa and deriving epithelial cell lines. An interdependence of enterocyte differentiation along the crypt-villus axis and fls485 chaperone activity might be possible.</p

Expression of the Lantibiotic Mersacidin in Bacillus amyloliquefaciens FZB42

Lantibiotics are small peptide antibiotics that contain the characteristic thioether amino acids lanthionine and methyllanthionine. As ribosomally synthesized peptides, lantibiotics possess biosynthetic gene clusters which contain the structural gene (lanA) as well as the other genes which are involved in lantibiotic modification (lanM, lanB, lanC, lanP), regulation (lanR, lanK), export (lanT(P)) and immunity (lanEFG). The lantibiotic mersacidin is produced by Bacillus sp. HIL Y-85,54728, which is not naturally competent

The Mitochondrial Chaperone Protein TRAP1 Mitigates α-Synuclein Toxicity

Overexpression or mutation of α-Synuclein is associated with protein aggregation and interferes with a number of cellular processes, including mitochondrial integrity and function. We used a whole-genome screen in the fruit fly Drosophila melanogaster to search for novel genetic modifiers of human [A53T]α-Synuclein–induced neurotoxicity. Decreased expression of the mitochondrial chaperone protein tumor necrosis factor receptor associated protein-1 (TRAP1) was found to enhance age-dependent loss of fly head dopamine (DA) and DA neuron number resulting from [A53T]α-Synuclein expression. In addition, decreased TRAP1 expression in [A53T]α-Synuclein–expressing flies resulted in enhanced loss of climbing ability and sensitivity to oxidative stress. Overexpression of human TRAP1 was able to rescue these phenotypes. Similarly, human TRAP1 overexpression in rat primary cortical neurons rescued [A53T]α-Synuclein–induced sensitivity to rotenone treatment. In human (non)neuronal cell lines, small interfering RNA directed against TRAP1 enhanced [A53T]α-Synuclein–induced sensitivity to oxidative stress treatment. [A53T]α-Synuclein directly interfered with mitochondrial function, as its expression reduced Complex I activity in HEK293 cells. These effects were blocked by TRAP1 overexpression. Moreover, TRAP1 was able to prevent alteration in mitochondrial morphology caused by [A53T]α-Synuclein overexpression in human SH-SY5Y cells. These results indicate that [A53T]α-Synuclein toxicity is intimately connected to mitochondrial dysfunction and that toxicity reduction in fly and rat primary neurons and human cell lines can be achieved using overexpression of the mitochondrial chaperone TRAP1. Interestingly, TRAP1 has previously been shown to be phosphorylated by the serine/threonine kinase PINK1, thus providing a potential link of PINK1 via TRAP1 to α-Synuclein

Transcriptome-Based Network Analysis Reveals a Spectrum Model of Human Macrophage Activation

SummaryMacrophage activation is associated with profound transcriptional reprogramming. Although much progress has been made in the understanding of macrophage activation, polarization, and function, the transcriptional programs regulating these processes remain poorly characterized. We stimulated human macrophages with diverse activation signals, acquiring a data set of 299 macrophage transcriptomes. Analysis of this data set revealed a spectrum of macrophage activation states extending the current M1 versus M2-polarization model. Network analyses identified central transcriptional regulators associated with all macrophage activation complemented by regulators related to stimulus-specific programs. Applying these transcriptional programs to human alveolar macrophages from smokers and patients with chronic obstructive pulmonary disease (COPD) revealed an unexpected loss of inflammatory signatures in COPD patients. Finally, by integrating murine data from the ImmGen project we propose a refined, activation-independent core signature for human and murine macrophages. This resource serves as a framework for future research into regulation of macrophage activation in health and disease

Averting biodiversity collapse in tropical forest protected areas

The rapid disruption of tropical forests probably imperils global biodiversity more than any other contemporary phenomenon¹⁻³. With deforestation advancing quickly, protected areas are increasingly becoming final refuges for threatened species and natural ecosystem processes. However, many protected areas in the tropics are themselves vulnerable to human encroachment and other environmental stresses⁴⁻⁹. As pressures mount, it is vital to know whether existing reserves can sustain their biodiversity. A critical constraint in addressing this question has been that data describing a broad array of biodiversity groups have been unavailable for a sufficiently large and representative sample of reserves. Here we present a uniquely comprehensive data set on changes over the past 20 to 30 years in 31 functional groups of species and 21 potential drivers of environmental change, for 60 protected areas stratified across the world’s major tropical regions. Our analysis reveals great variation in reserve ‘health’: about half of all reserves have been effective or performed passably, but the rest are experiencing an erosion of biodiversity that is often alarmingly widespread taxonomically and functionally. Habitat disruption, hunting and forest-product exploitation were the strongest predictors of declining reserve health. Crucially, environmental changes immediately outside reserves seemed nearly as important as those inside in determining their ecological fate, with changes inside reserves strongly mirroring those occurring around them. These findings suggest that tropical protected areas are often intimately linked ecologically to their surrounding habitats, and that a failure to stem broad-scale loss and degradation of such habitats could sharply increase the likelihood of serious biodiversity declines.Keywords: Ecology, Environmental scienc

Arnold, Karl-Heinz / Gröschner, Alexander / Hascher, Tina (Hg.): Schulpraktika in der Lehrerbildung / Pedagogical field experiences in teacher education, Theoretische Grundlagen, Konzeptionen, Prozesse und Effekte / Theoretical foundations, programmes, processes, and effects. Münster / New York: Waxmann 2014. [Rezension]

Rezension von: Karl-Heinz Arnold / Alexander Gröschner / Tina Hascher (Hrsg.): Schulpraktika in der Lehrerbildung / Pedagogical field experiences in teacher education. Theoretische Grundlagen, Konzeptionen, Prozesse und Effekte / Theoretical foundations, programmes, processes, and effects. Münster / New York: Waxmann 2014, 400 S. ISBN 978-3-8309-3057-

Jürgen Abel / Gabriele Faust (Hrsg.): Wirkt Lehrerbildung? Antworten aus der empirischen Forschung. Münster u.a.: Waxmann 2010 (352 S.) [Rezension]

Rezension von: Jürgen Abel / Gabriele Faust (Hrsg.): Wirkt Lehrerbildung? Antworten aus der empirischen Forschung. Münster u.a.: Waxmann 2010 (352 S.; ISBN 978-3-8309-2318-3; 29,90 EUR)

Acyl-CoA Synthetase 5-assoziierte Apoptose- und Lipidsignalwege in der Pathogenese der nichtalkoholischen Fettlebererkrankung

With the increasing incidence of obesity, super- and malnutrition in Western countries, fatty acid and lipid-induced metabolic diseases have become a growing problem. In particular, nonalcoholic fatty liver disease (NAFLD) which is associated with an increased risk of cardiometabolic dysfunction and diabetes type 2 affects a rising proportion of the world’s population. Fatty liver, a reversible condition and the initial stage in the pathogenesis of NAFLD can progress to severe acute and chronic liver disorders, including nonalcoholic steatohepatitis, liver fibrosis/cirrhosis and hepatocellular carcinoma. Dysfunction in hepatocellular lipid metabolism and subsequent hepatocyte lipoapoptosis by accumulation of fatty acids are strongly implicated in disease progression. The initial step in fatty acid and lipid metabolism is the activation of long chain fatty acids to acyl-CoAs which is catalyzed by long chain acyl-CoA synthetases (ACSL). Of the five mammalian ACSL isoformes known, ACSL5 is the only one that is located on mitochondria and potentially involved in apoptosis regulation. The goal of the present study was to characterize the role of ACSL5 in NAFLD pathogenesis and, particularly, to analyze its function in fatty liver manifestation and progression to hepatocellular apoptosis. Using in vivo and in vitro models of hepatocyte steatosis as well as plasmid-mediated stable gene transfer and small interfering RNA-mediated gene silencing, it was demonstrated that ACSL5 expression was strongly induced by fatty acid uptake and lipid accumulation in hepatocytes. Overexpression of ACSL5 decreased hepatocyte viability and increased susceptibility to TRAIL and TNFα, whereas knock down of ACSL5 reduced apoptosis susceptibility in fatty acid-treated hepatocytes. Lipid analytical mass spectrometry revealed the involvement of hepatic sphingolipid metabolism in ACSL5-induced apoptosis sensitization. By channelling acyl-CoAs into sphingolipid metabolism, high ACSL5 activity increased de novo synthesis of proapoptotic sphingolipids including ceramide and sphingosine. Furthermore, ACSL5 induced structural modifications of mitochondria and mediated activation of mitochondrial apoptosis signalling. In summary, this study gives evidence that ACSL5 plays a putative role in promoting fatty acid-induced lipoapoptosis in hepatocytes and ACSL5-associated lipid de novo synthesis in the pathogenesis of NAFLD