Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease

BACKGROUND: Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes. METHODS: We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization. RESULTS: During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events. CONCLUSIONS: Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)

Journal of Leukocyte Biology / NCOR1 : a new player on the field of T cell development

Nuclear receptor corepressor 1 (NCOR1) is a transcriptional corepressor that links chromatinmodifying enzymes with genespecific transcription factors. Although identified more than 20 years ago as a corepressor of nuclear receptors, the role of NCOR1 in T cells remained only poorly understood. However, recent studies indicate that the survival of developing thymocytes is regulated by NCOR1, revealing an essential role for NCOR1 in the T cell lineage. In this review, we will briefly summarize basic facts about NCOR1 structure and functions. We will further summarize studies demonstrating an essential role for NCOR1 in controlling positive and negative selection of thymocytes during T cell development. Finally, we will discuss similarities and differences between the phenotypes of mice with a T cellspecific deletion of NCOR1 or histone deacetylase 3 (HDAC3), because HDAC3 is the predominant member of the HDAC family that interacts with NCOR1 corepressor complexes. With this review we aim to introduce NCOR1 as a new player in the team of transcriptional coregulators that control T cell development and thus the generation of the peripheral T cell pool.(VLID)342387

Histone deacetylase 1 controls CD4+ T cell trafficking in autoinflammatory diseases.

CD4+ T cell trafficking is a fundamental property of adaptive immunity. In this study, we uncover a novel role for histone deacetylase 1 (HDAC1) in controlling effector CD4+ T cell migration, thereby providing mechanistic insight into why a T cell-specific deletion of HDAC1 protects against experimental autoimmune encephalomyelitis (EAE). HDAC1-deficient CD4+ T cells downregulated genes associated with leukocyte extravasation. In vitro, HDAC1-deficient CD4+ T cells displayed aberrant morphology and migration on surfaces coated with integrin LFA-1 ligand ICAM-1 and showed an impaired ability to arrest on and to migrate across a monolayer of primary mouse brain microvascular endothelial cells under physiological flow. Moreover, HDAC1 deficiency reduced homing of CD4+ T cells into the intestinal epithelium and lamina propria preventing weight-loss, crypt damage and intestinal inflammation in adoptive CD4+ T cell transfer colitis. This correlated with reduced expression levels of LFA-1 integrin chains CD11a and CD18 as well as of selectin ligands CD43, CD44 and CD162 on transferred circulating HDAC1-deficient CD4+ T cells. Our data reveal that HDAC1 controls T cell-mediated autoimmunity via the regulation of CD4+ T cell trafficking into the CNS and intestinal tissues

The rRNA m(6)A methyltransferase METTL5 is involved in pluripotency and developmental programs

Contains fulltext : 219165.pdf (publisher's version ) (Open Access

The Non-receptor Tyrosine Kinase Tec Controls Assembly and Activity of the Noncanonical Caspase-8 Inflammasome

<div><p>Tec family kinases are intracellular non-receptor tyrosine kinases implicated in numerous functions, including T cell and B cell regulation. However, a role in microbial pathogenesis has not been described. Here, we identified Tec kinase as a novel key mediator of the inflammatory immune response in macrophages invaded by the human fungal pathogen <i>C. albicans</i>. Tec is required for both activation and assembly of the noncanonical caspase-8, but not of the caspase-1 inflammasome, during infections with fungal but not bacterial pathogens, triggering the antifungal response through IL-1β. Furthermore, we identify dectin-1 as the pathogen recognition receptor being required for Syk-dependent Tec activation. Hence, Tec is a novel innate-specific inflammatory kinase, whose genetic ablation or inhibition by small molecule drugs strongly protects mice from fungal sepsis. These data demonstrate a therapeutic potential for Tec kinase inhibition to combat invasive microbial infections by attenuating the host inflammatory response.</p></div

The corepressor NCOR1 regulates the survival of single-positive thymocytes

Nuclear receptor corepressor 1 (NCOR1) is a transcriptional regulator bridging repressive chromatin modifying enzymes with transcription factors. NCOR1 regulates many biological processes, however its role in T cells is not known. Here we show that Cd4-Cre-mediated deletion of NCOR1 (NCOR1 cKOCd4) resulted in a reduction of peripheral T cell numbers due to a decrease in single-positive (SP) thymocytes. In contrast, double-positive (DP) thymocyte numbers were not affected in the absence of NCOR1. The reduction in SP cells was due to diminished survival of NCOR1-null postselection TCRhiCD69+ and mature TCRhiCD69 thymocytes. NCOR1-null thymocytes expressed elevated levels of the pro-apoptotic factor BIM and showed a higher fraction of cleaved caspase 3-positive cells upon TCR stimulation ex vivo. However, staphylococcal enterotoxin B (SEB)-mediated deletion of V8+ CD4SP thymocytes was normal, suggesting that negative selection is not altered in the absence of NCOR1. Finally, transgenic expression of the pro-survival protein BCL2 restored the population of CD69+ thymocytes in NCOR1 cKOCd4 mice to a similar percentage as observed in WT mice. Together, these data identify NCOR1 as a crucial regulator of the survival of SP thymocytes and revealed that NCOR1 is essential for the proper generation of the peripheral T cell pool.(VLID)463721

Tec is required for the assembly of the caspase-8 inflammasome.

<p>(<b>a</b>) Caspase-8 activity after 60 Min of stimulation with <i>C. albicans</i> of cells left untreated, knockdown of a non-target (nTG; 25 nM) or respective siRNA knock down (25 nM) after 72 hrs of incubation; chemiluminenscence of unstimulated cells and <i>C. albicans</i> only was subtracted. (<b>b</b>–<b>e</b>) Immunoblot analysis of CARD9, Bcl-10, MALT1, ASC and caspase-8 (Casp8) after immunoprecipitation (IP) with antibodies against CARD9 (<b>b</b>), MALT1 (<b>c</b>), ASC (<b>d</b>) and caspase-8 (<b>e</b>) from whole-cell lysates of BMMs left unstimulated (-) or stimulated with <i>C. albicans</i> for 60 Min. Data are representative of two independent experiments for each IP. (<b>f</b>) Immunoblot analysis of p-Src, p-Syk, p-PLCγ2, p-PKCδ and p-RAF1 during the course of BMM infection with <i>C. albicans</i>. (<b>g</b>) <i>In vitro</i> kinase assay; Tec was immunoprecipitated from unstimulated BMMs and incubated with recombinant active Syk, BSA (70 ng each) and adenosine triphosphate (ATP, 200 nM) for 30 Min at 30°C; active phosphorylated Tec was detected with α-p-Tyr antibodies. (<b>h</b>) <i>In vitro</i> kinase assay; PLCγ2 was immunoprecipitated from unstimulated BMMs and incubated with active Tec, BSA (70 ng each) and adenosine triphosphate (ATP, 200 nM) for 30 Min at 30°C; active PLCγ2 was detected with α-p-PLCγ2 antibody. (<b>i</b>) Immunoblot of activated Tec and p-Src/p-Syk in cell lysates after stimulation with <i>C. albicans</i> and parallel Syk inhibition with R406 (3 µM); lysates were enriched for phospho-proteins. Data are representative of at least two (<b>b</b>–<b>i</b>) or three (<b>a</b>) independent experiments. Mean and SD are shown (<b>a</b>).</p

Dectin-1 is required for Tec-dependent caspase-8 activation.

<p>(<b>a</b>) Caspase-8 activity after 60 Min stimulation of BMMs with <i>C. albicans</i> (Ca), dimethylsulfoxide (DMSO), CytochalasinD (CytoD; 2 µM) or Dynasore (80 µM); chemiluminenscence of unstimulated cells, cells with respective inhibitor, cells with DMSO or <i>C. albicans</i> only was subtracted. (<b>b</b>) Caspase-8 activity after 60 Min of stimulation with <i>C. albicans</i> only (Ca) or with dimethylsulfoxide (DMSO) or BafilomycinA₁ (BafiloA₁; 30 nM) and Ca; chemiluminenscence of unstimulated cells, cells with respective inhibitor, cells with DMSO or <i>C. albicans</i> only was subtracted. (<b>c</b>) Caspase-8 activity after 60 Min of stimulation with <i>C. albicans</i> only (Ca) or with dimethylsulfoxide (DMSO), Syk Inhibitor R406 (3 µM), Src Inhibitor PP2 (5 µM) or the non-functional analogon PP3 (5 µM) and Ca; chemiluminenscence of unstimulated cells, cells with respective inhibitor, cells with DMSO or <i>C. albicans</i> only was subtracted. (<b>d</b>) Caspase-8 activity after 60 Min stimulation with <i>C. albicans</i> only (Ca) in BMMs of indicated genotype; chemiluminenscence of unstimulated cells or <i>C. albicans</i> only was subtracted. (<b>e</b>) Caspase-8 activity after 60 Min of stimulation with <i>C. albicans</i> only (Ca) in WT BMMs blocked with indicated antibodies (all 10 µg/ml) and respective isotype control (10 µg/ml); chemiluminenscence of unstimulated cells, cells treated with antibody only or <i>C. albicans</i> only was subtracted. (<b>f</b>) Immunoblot of Tec activation of cell lysates after stimulation with <i>C. albicans</i>; lysates were enriched for phospho-protein fraction using respective kit. Data are representative of at least two (<b>f</b>), three (<b>d</b>,<b>e</b>) or four (<b>a</b>–<b>c</b>) independent experiments. Mean and SD are shown.</p

Fungal β-glucans activate caspase-8 in murine BMMs.

<p>(<b>a</b>) Caspase-8 activity after 60 Min stimulation of BMMs with <i>C. albicans</i> (Ca) or curdlan (200 µg/ml); dectin-1 was blocked with laminarin (500 µg/ml); chemiluminenscence of unstimulated cells, cells with laminarin only or <i>C. albicans</i> only was subtracted. (<b>b</b>) ELISA of IL-1β in supernatants of BMMs after stimulation with <i>C. albicans</i> only (Ca) or curdlan (200 µg/ml); dectin-1 was blocked with laminarin (500 µg/ml). (<b>c</b>) Caspase-8 activity after 60 Min of stimulation with <i>C. albicans</i> only (Ca), heat-killed Ca (10 Min on 70°C)); chemiluminenscence of unstimulated cells or <i>C. albicans</i> resp. <i>Candida glabrata</i> only was subtracted. (<b>d</b>) ELISA of IL-1β in supernatants of BMMs after stimulation with <i>C. albicans</i> only (Ca), heat-killed Ca (10 Min on 70°C), <i>efg1</i>Δ/Δ or <i>efg1</i>Δ/Δ <i>cph1</i>Δ/Δ Ca-mutants or left unstimulated (-). (<b>e,f</b>) Caspase-8 activity after 60 Min of stimulation with <i>L. monocytogenes</i>. <i>S. aureus</i>, <i>P. aeruginosa</i> or <i>S. pyogenes</i>; chemiluminenscence of unstimulated cells or bacteria only was subtracted. ELISA of IL-1β in supernatants of BMMs after stimulation with <i>L. monogenes</i>. <i>S. aureus</i>, <i>P. aeruginosa</i> or <i>S. pyogenes</i> or left unstimulated (-). Data are representative of at least three independent experiments. Mean and SD are shown.</p