Inhibition of Class I Histone Deacetylase Activity Blocks the Induction of TNFAIP3 Both Directly and Indirectly via the Suppression of Endogenous TNF-α

Histone deacetylase inhibitors (HDIs) are promising drugs for the treatment of inflammatory diseases. However, their therapeutical exploitation is slowed down by severe adverse manifestations that can hardly be foreseen, mainly due to incomplete knowledge of how HDIs impact the delicate balance of inflammatory mediators. In this work, we characterized the effects of the HDI trichostatin A (TSA) on the expression of TNFAIP3, which is a crucial inhibitor of the classical NF-kB pathway and an LPS-induced negative feedback regulator. The accumulation of TNFAIP3 mRNA after LPS stimulation showed biphasic behavior, with one wave within the first hour of stimulation and a second wave several hours later, which were both reduced by TSA. By using inhibition and knockdown approaches, we identified two temporally and mechanistically distinct modes of action. The first wave of TNAIP3 accumulation was directly blunted by the histone deacetylase (HDAC) blockade. By contrast, the second wave was decreased mainly because of the lack of endogenous TNF-α induction, which, in turn, depended on the intact HDAC activity. In both cases, class I HDACs appeared to play a nonredundant role, with HDAC3 required, but not sufficient, for TNF-α and TNFAIP3 induction. In addition to TNFAIP3, TNF-α is known to induce many response genes that orchestrate the inflammatory cascade. Thus, suppression of TNF-α may represent a general mechanism through which HDIs regulate a selected set of target genes

Morphometric analysis of lymphatics vessels in fibrotic human lung

In pulmonary fibrosis, the usual interstitial pneumonia (UIP) pattern is characterised by heterogeneous, patchy fibrosis, with areas of normal lung adjacent to areas of complete destruction (honeycombing) and by fibroblastic foci (FF). The NSIP pattern which is characteristic of systemic sclerosis, is characterised by a more homogeneous involvement of the lung without honeycombing and FF. Little is known on lymphatic vessels in lung fibrosis. Defective lymphatic clearance could lead to prolonged exposure to pathogenic antigens and/or pro-inflammatory/pro-fibrotic mediators. We evaluated the distribution and morphology of lymphatic vessels in lung biopsies of 6 patients with UIP, 6 NSIP and 5 controls. Consecutive sections were stained with Movat’s pentachrome and with double immunostaining for von Willebrand factor and podoplanin (D2-40). Area, perimeter and position were recorded for vessels with a diameter > 5µm. We investigated separately in lintralobular, sub-pleural, and interlobular spaces. Lymphatics were consistently larger in subpleural spaces and in interlobular septa than in intralobular tissue. In the latter, the density of lymphatic vessels was significantly reduced in NSIP and in UIP (both 21±1 mm-2) compared to controls (35±4 mm-2) . In controls, 85±6% of the intralobular lymphatics were close (< 100 µm) to a blood vessel, and only 5±4% were in the proximity of bronchoalveolar spaces, while in the disease groups they were less frequently perivascular (NSIP 55 ±3%, UIP 56 ±2%) and more frequently associated with the bronchoalveolar lumen (NSIP 85 ±3%, UIP 69 ±2%). By contrast, in interlobular septa, lymphatic density was significantly increased in NSIP (303±28 mm-2) and in UIP (286±124 mm-2) compared to controls (96±69 mm-2). No differences in lymphatic density was seen in subpleural spaces. Thus, our data show a marked redistribution of lymphatic vessels within the lung in pulmonary fibrosis, without noticeable differences between the NSIP and UIP patterns

The PDE4 Inhibitor Tanimilast Restrains the Tissue-Damaging Properties of Human Neutrophils

: Neutrophils, the most abundant subset of leukocytes in the blood, play a pivotal role in host response against invading pathogens. However, in respiratory diseases, excessive infiltration and activation of neutrophils can lead to tissue damage. Tanimilast-international non-proprietary name of CHF6001-is a novel inhaled phosphodiesterase 4 (PDE4) inhibitor in advanced clinical development for the treatment of chronic obstructive pulmonary disease (COPD), a chronic inflammatory lung disease where neutrophilic inflammation plays a key pathological role. Human neutrophils from healthy donors were exposed to pro-inflammatory stimuli in the presence or absence of tanimilast and budesonide-a typical inhaled corticosteroid drug-to investigate the modulation of effector functions including adherence to endothelial cells, granule protein exocytosis, release of extracellular DNA traps, cytokine secretion, and cell survival. Tanimilast significantly decreased neutrophil-endothelium adhesion, degranulation, extracellular DNA traps casting, and cytokine secretion. In contrast, it promoted neutrophil survival by decreasing both spontaneous apoptosis and cell death in the presence of pro-survival factors. The present work suggests that tanimilast can alleviate the severe tissue damage caused by massive recruitment and activation of neutrophils in inflammatory diseases such as COPD

The chemerin/CMKLR1 axis regulates intestinal graft-versus-host disease

: Gastrointestinal graft-versus-host disease (GvHD) is a major cause of mortality and morbidity following allogeneic bone marrow transplantation (allo-BMT). Chemerin is a chemotactic protein that recruits leukocytes to inflamed tissues by interacting with ChemR23/CMKLR1, a chemotactic receptor expressed by leukocytes, including macrophages. During acute GvHD, chemerin plasma levels were strongly increased in allo-BM-transplanted mice. The role of the chemerin/CMKLR1 axis in GvHD was investigated using Cmklr1-KO mice. WT mice transplanted with an allogeneic graft from Cmklr1-KO donors (t-KO) had worse survival and more severe GvHD. Histological analysis demonstrated that the gastrointestinal tract was the organ mostly affected by GvHD in t-KO mice. The severe colitis of t-KO mice was characterized by massive neutrophil infiltration and tissue damage associated with bacterial translocation and exacerbated inflammation. Similarly, Cmklr1-KO recipient mice showed increased intestinal pathology in both allogeneic transplant and dextran sulfate sodium-induced colitis. Notably, the adoptive transfer of WT monocytes into t-KO mice mitigated GvHD manifestations by decreasing gut inflammation and T cell activation. In patients, higher chemerin serum levels were predictive of GvHD development. Overall, these results suggest that CMKLR1/chemerin may be a protective pathway for the control of intestinal inflammation and tissue damage in GvHD

Genetic determinants in a critical domain of ns5a correlate with hepatocellular carcinoma in cirrhotic patients infected with hcv genotype 1b

HCV is an important cause of hepatocellular carcinoma (HCC). HCV NS5A domain‐1 interacts with cellular proteins inducing pro‐oncogenic pathways. Thus, we explore genetic variations in NS5A domain‐1 and their association with HCC, by analyzing 188 NS5A sequences from HCV genotype‐1b infected DAA‐naïve cirrhotic patients: 34 with HCC and 154 without HCC. Specific NS5A mutations significantly correlate with HCC: S3T (8.8% vs. 1.3%, p = 0.01), T122M (8.8% vs. 0.0%, p < 0.001), M133I (20.6% vs. 3.9%, p < 0.001), and Q181E (11.8% vs. 0.6%, p < 0.001). By multivariable analysis, the presence of >1 of them independently correlates with HCC (OR (95%CI): 21.8 (5.7–82.3); p < 0.001). Focusing on HCC‐group, the presence of these mutations correlates with higher viremia (median (IQR): 5.7 (5.4–6.2) log IU/mL vs. 5.3 (4.4–5.6) log IU/mL, p = 0.02) and lower ALT (35 (30–71) vs. 83 (48–108) U/L, p = 0.004), suggesting a role in enhancing viral fitness without affecting necroinflammation. Notably, these mutations reside in NS5A regions known to interact with cellular proteins crucial for cell‐cycle regulation (p53, p85‐PIK3, and β‐ catenin), and introduce additional phosphorylation sites, a phenomenon known to ameliorate NS5A interaction with cellular proteins. Overall, these results provide a focus for further investigations on molecular bases of HCV‐mediated oncogenesis. The role of these NS5A domain‐1 mutations in triggering pro‐oncogenic stimuli that can persist also despite achievement of sustained virological response deserves further investigation

Nota sulla dimensione dei nidi e successo delle covate di Cannaiola (Acrocephalus scirpaceus) in fragmiteti del Litorale Romano (Italia Centrale)

We report some nesting and breeding parameters of the reed warbler in reedbeds patches. The nests were found only in pure reedbeds characterised by young stems, above or near water or on dry ground. In average, each nests was built on 3.06 Phragmites stems (± 1.06, range: 2-5, n = 16), at 1.31 m of height (0.31 ± , range from 0.70 to 2; n = 17). The average size of broods observed was determined to be 3.75 (± 0.75, range 2-5, n = 12). We observed 2.89 chicks (± 1.76, range 0-5, n = 9) in the 12 nests in which eggs were found

Conservation of species occupying ephemeral and patchy habitats in agricultural landscapes: The case of the Eurasian Reed Warbler

Habitat loss and fragmentation are amongst the main threats for animal populations. These two processes are mainly due to the conversion of natural habitats to agroecosystems and have effects at different spatial scales. The identification of their lands

Conservation of species occupying ephemeral and patchy habitats in agricultural landscapes: the case of the Eurasian Reed Warbler

Habitat loss and fragmentation are amongst the main threats for animal populations. These two processes are mainly due to the conversion of natural habitats to agroecosystems and have effects at different spatial scales. The identification of their landscape-scale effects is the first step to target habitat management toward specific actions. At the same time the role of single habitat patches should not be overlooked, since some processes, like habitat degradation, occur at the patch scale. Multi-scale studies allow evaluating the relative role of patch-scale versus landscape-scale factors on species distribution allowing the identification of the spatial scale toward which conservation and management actions should be targeted. We studied the distribution of the Eurasian reed warbler (Acrocephalus scirpaceus) in ephemeral reed beds embedded in an agricultural landscape. After separating the independent, landscape-scale effects of habitat loss and fragmentation per se, we evaluated the role of patch-scale characteristics. Our multi-scale analysis showed that landscape characteristics are the most important features, while the role of patch is weaker and varies depending on the landscape context. We found no effects of fragmentation per se and of habitat structure in single patches. Our results suggest that for some species adapted to live in naturally ephemeral and patchy habitats, landscape context could be more important than patch-scale factors. From a conservation point of view, for such species the management actions should be prioritized toward increasing landscape suitability rather than that of single habitat fragments

Dendritic cell subsets in cancer immunity and tumor antigen sensing.

Dendritic cells (DCs) exhibit a specialized antigen-presenting function and play crucial roles in both innate and adaptive immune responses. Due to their ability to cross-present tumor cell-associated antigens to naïve T cells, DCs are instrumental in the generation of specific T-cell-mediated antitumor effector responses in the control of tumor growth and tumor cell dissemination. Within an immunosuppressive tumor microenvironment, DC antitumor functions can, however, be severely impaired. In this review, we focus on the mechanisms of DC capture and activation by tumor cell antigens and the role of the tumor microenvironment in shaping DC functions, taking advantage of recent studies showing the phenotype acquisition, transcriptional state and functional programs revealed by scRNA-seq analysis. The therapeutic potential of DC-mediated tumor antigen sensing in priming antitumor immunity is also discussed

Effect of habitat amount, configuration and quality in fragmented landscapes

Landscape changes are driven by several factors, such as habitat loss, fragmentation and degradation. Untangling the independent contribution of each process is crucial, since effective conservation actions depend on the clear identification of the threatening process. Nevertheless in most landscape scale studies configuration metrics are often grouped together without further distinguishing between different habitat properties (e.g. subdivision vs scatteredness of habitat patches) furthermore few landscape scale studies have included measurements of habitat quality thus possibly overlooking important interactions with landscape structure. In order to tackle these issues we carried out a large scale field study following an experimental design that allowed us to disentangle the independent role of landscape processes. We chose the European reed warbler (Acrocephalus scirpaceus) as model species due to its ecological characteristics. Probability of the reed warbler presence increased in landscapes with increasing amounts of habitat and increased with the proportion of flooded reed bed patches in the landscape: variables related to the configuration of habitat, instead, did not play a relevant role in shaping distribution patterns. Results of the modelling inference revealed a crucial complementarity between habitat quality and landscape structure: regulation of the amount of water in the canals increased the habitat suitability of patches only for landscapes with intermediate amounts of habitat. (C) 2012 Elsevier Masson SAS. All rights reserved