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Signal transducer and activator of transcription 3 (STAT3) triggered production of Th-17 cytokines mediates protective immunity against fungi. Mutations affecting the STAT3/interleukin 17 (IL-17) pathway cause selective susceptibility to fungal (Candida) infections, a hallmark of chronic mucocutaneous candidiasis (CMC). In patients with autosomal dominant CMC, we and others previously reported defective Th17 responses and underlying gain-of-function (GOF) STAT1 mutations, but how this affects STAT3 function leading to decreased IL-17 is unclear. We also assessed how GOF-STAT1 mutations affect STAT3 activation, DNA binding, gene expression, cytokine production, and epigenetic modifications. We excluded impaired STAT3 phosphorylation, nuclear translocation, and sequestration of STAT3 into STAT1/STAT3 heterodimers and confirm significantly reduced transcription of STAT3-inducible genes (RORC/IL-17/IL-22/IL-10/c-Fos/SOCS3/cMyc) as likely underlying mechanism. STAT binding to the high affinity sis-inducible element was intact but binding to an endogenous STAT3 DNA target was impaired. Reduced STAT3-dependent gene transcription was reversed by inhibiting STAT1 activation with fludarabine or enhancing histone, but not STAT1 or STAT3 acetylation with histone deacetylase (HDAC) inhibitors trichostatin A or ITF2357. Silencing HDAC1, HDAC2, and HDAC3 indicated a role for HDAC1 and 2. Reduced STAT3-dependent gene transcription underlies low Th-17 responses in GOF-STAT1 CMC, which can be reversed by inhibiting acetylation, offering novel targets for future therapies.Correspondence: Dr. Desa Lilic e-mail: desa.lilic@ncl.ac.uk * Both authors contributed equally to this work.C 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim www.eji-journal.eu Eur. J. Immunol. 2015. 45: 2834-2846 Immunity to infection 2835 Keywords: Chronic mucocutaneous candidiasis (CMC) HDAC inhibitors IL-17 STAT1 gain-of-function mutation STAT3 STAT1 inhibitorsAdditional supporting information may be found in the online version of this article at the publisher's web-site IntroductionPatients with chronic mucocutaneous candidiasis (CMC) present with recurrent or persistent infections of the skin, nails, and mucosal membranes with the fungus Candida [1]. Candida is an opportunistic yeast that does not cause disease in healthy individuals despite inhabiting bodily surfaces as it is controlled by immune mechanisms, specifically Th-17 cells and cytokines produced by them [2]. Mucosal infections with Candida species indicate an underlying T-cell deficiency, which is most often secondary to immunosuppressive and/or chemotherapy, antibiotics, biological therapies, HIV, or other permissive circumstances. However, in rare patients, these infections present as a severe syndrome coined CMC, a primary immune deficiency in which the underlying cause is a genetic mutation affecting immune pathways essential for fungal protection [3]. Research in primary immune deficiency patients with isolated CMC has documented the crucial role of the signal transducer and activator of tra...

This prospective quasi-experimental study from the NASAM (National Approach to Standardize and Improve Mechanical Ventilation) collaborative assessed the impact of evidence-based practices including subglottic suctioning, daily assessment for spontaneous awakening trial (SAT), spontaneous breathing trial (SBT), head of bed elevation, and avoidance of neuromuscular blockers unless otherwise indicated. The study outcomes included VAE (primary) and intensive care unit (ICU) mortality. Changes in daily care process measures and outcomes were evaluated using repeated measures mixed modeling. The results were reported as incident rate ratio (IRR) for each additional month with 95% confidence interval (CI). A comprehensive program that included education on evidence-based practices for optimal care of mechanically ventilated patients with real-time benchmarking of daily care process measures to drive improvement in forty-two ICUs from 26 hospitals in Saudi Arabia (>27,000 days of observation). Compliance with subglottic suctioning, SAT and SBT increased monthly during the project by 3.5%, 2.1% and 1.9%, respectively (IRR 1.035, 95%CI 1.007–1.064, p = 0.0148; 1.021, 95% CI 1.010–1.032, p = 0.0003; and 1.019, 95%CI 1.009–1.029, p = 0.0001, respectively). The use of neuromuscular blockers decreased monthly by 2.5% (IRR 0.975, 95%CI 0.953–0.998, p = 0.0341). The compliance with head of bed elevation was high at baseline and did not change over time. Based on data for 83153 ventilator days, VAE rate was 15.2/1000 ventilator day (95%CI 12.6–18.1) at baseline and did not change during the project (IRR 1.019, 95%CI 0.985–1.053, p = 0.2812). Based on data for 8523 patients; the mortality was 30.4% (95%CI 27.4–33.6) at baseline, and decreased monthly during the project by 1.6% (IRR 0.984, 95%CI 0.973–0.996, p = 0.0067). A national quality improvement collaborative was associated with improvements in daily care processes. These changes were associated with a reduction in mortality but not VAEs. Registration The study is registered in clinicaltrials.gov (NCT03790150).

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