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1.
Front Immunol ; 15: 1331731, 2024.
Article in English | MEDLINE | ID: mdl-38384473

ABSTRACT

The establishment of a virus infection is the result of the pathogen's ability to replicate in a hostile environment generated by the host's immune system. Here, we found that ISG15 restricts Dengue and Zika viruses' replication through the stabilization of its binding partner USP18. ISG15 expression was necessary to control DV replication driven by both autocrine and paracrine type one interferon (IFN-I) signaling. Moreover, USP18 competes with NS5-mediated STAT2 degradation, a major mechanism for establishment of flavivirus infection. Strikingly, reconstitution of USP18 in ISG15-deficient cells was sufficient to restore the STAT2's stability and restrict virus growth, suggesting that the IFNAR-mediated ISG15 activity is also antiviral. Our results add a novel layer of complexity in the virus/host interaction interface and suggest that NS5 has a narrow window of opportunity to degrade STAT2, therefore suppressing host's IFN-I mediated response and promoting virus replication.


Subject(s)
Dengue , Interferon Type I , Zika Virus Infection , Zika Virus , Humans , Interferon Type I/metabolism , Zika Virus Infection/genetics , Virus Replication , Dengue/genetics , Ubiquitins/metabolism , Cytokines/metabolism , Ubiquitin Thiolesterase/metabolism , STAT2 Transcription Factor/genetics , STAT2 Transcription Factor/metabolism
3.
Eur J Pharmacol ; 959: 176092, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37797676

ABSTRACT

Sepsis is a severe condition secondary to dysregulated host response to infection leading to tissue damage and organ dysfunction. Cannabinoid CB2 receptor has modulatory effects on the immune response. Therefore, this study investigated the effects of a cannabinoid CB2 receptor agonist on the local and systemic inflammatory process associated with pneumonia-induced sepsis. Pneumonia-induced sepsis was induced in mice by intratracheal inoculation of Klebsiella pneumoniae. Tissue and bronchoalveolar lavage (BAL) were collected 6, 24, or 48 h after surgery. Mice were treated with CB2 agonist (AM1241, 0.3 and 3 mg/kg, i.p.) and several parameters of inflammation were evaluated 24 h after sepsis induction. Polymorphonuclear cell migration to the infectious focus peaked 24 h after pneumonia-induced sepsis induction in male and female animals. Septic male mice presented a significant reduction of cannabinoid CB2 receptor density in the lung tissue after 24 h, which was not observed in females. CB2 expression in BAL macrophages was also reduced in septic animals. Treatment of septic mice with AM1241 reduced cell migration, local infection, myeloperoxidase activity, protein extravasation, and NOS-2 expression in the lungs. In addition, the treatment reduced plasma IL-1ß, increased IL-10 and reduced the severity and mortality of septic animals. These results suggest that AM1241 promotes an interesting balance in the inflammatory response, maintaining lung function and preventing organ injury. Therefore, cannabinoid CB2 receptors are potential targets to control the excessive inflammatory process that occurs in severe conditions, and agonists of these receptors can be considered promising adjuvants in pneumonia-induced sepsis treatment.


Subject(s)
Cannabinoids , Pneumonia , Sepsis , Female , Mice , Male , Animals , Cannabinoid Receptor Agonists/pharmacology , Pneumonia/drug therapy , Cannabinoids/pharmacology , Inflammation/drug therapy , Inflammation/metabolism , Receptors, Cannabinoid , Sepsis/complications , Sepsis/drug therapy , Sepsis/metabolism , Receptor, Cannabinoid, CB2 , Receptor, Cannabinoid, CB1
5.
Acta Chir Belg ; 123(4): 337-344, 2023 Aug.
Article in English | MEDLINE | ID: mdl-34779697

ABSTRACT

BACKGROUND: Pancreatic tumours are frequently associated with obstructive jaundice requiring preoperative biliary drainage (PBD) before pancreatoduodenectomy (PD), exposing patients to infectious complications. This study aims to compare postoperative complications after PD with or without PBD and to analyse bile bacteriology and antibiotic susceptibility. METHODS: All patients undergoing PD between 2014 and 2019 were retrospectively evaluated, and postoperative outcomes were compared according to PBD use. Prophylactic narrow-spectrum antibiotic therapy was given for 24 h, then adapted according to bacteriologic profile. Intraoperative bile cultures and antibiograms were collected. RESULTS: Among 164 patients with intraoperative bile culture during PD (75 PBD+, 89 PBD-), an infected bile was observed in 95% and 70% of PBD + and PBD- groups, respectively (p < 0.001). Postoperative mortality and severe morbidity including infectious complications were similar between groups (5% and 15%). The median duration of antibiotherapy was longer in PBD + compared to PBD- groups (9 vs. 2 days, p = 0.009). Malignant indication and PBD were associated with bile contamination using univariate analysis, and PBD was significantly relevant at multivariate analysis. Most common pathogens identified in bile cultures were Escherichia coli, Klebsiella spp. and Enterobacter spp. Overall antibiotic susceptibility to commonly used antibiotics was decreased, including those used in our local guidelines. CONCLUSIONS: PBD exposes nearly 100% of patients undergoing PD to bile infection and an increased duration of postoperative antimicrobial therapy, without increasing infectious complications in this study. Adaptation of antimicrobial prophylaxis should be further evaluated according to performance of PBD and local epidemiology, in order to avoid overuse of antibiotics.


Subject(s)
Pancreaticoduodenectomy , Preoperative Care , Humans , Pancreaticoduodenectomy/adverse effects , Retrospective Studies , Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis/adverse effects , Postoperative Complications/etiology , Drainage
6.
Front Immunol ; 13: 1042463, 2022.
Article in English | MEDLINE | ID: mdl-36311766

ABSTRACT

Zika virus (ZIKV) is a single-strand RNA mosquito-borne flavivirus with significant public health impact. ZIKV infection induces double-strand DNA breaks (DSBs) in human neural progenitor cells that may contribute to severe neuronal manifestations in newborns. The DNA-PK complex plays a critical role in repairing DSBs and in the innate immune response to infection. It is unknown, however, whether DNA-PK regulates ZIKV infection. Here we investigated the role of DNA-PKcs, the catalytic subunit of DNA-PK, during ZIKV infection. We demonstrate that DNA-PKcs restricts the spread of ZIKV infection in human epithelial cells. Increased ZIKV replication and spread in DNA-PKcs deficient cells is related to a notable decrease in transcription of type I and III interferons as well as IFIT1, IFIT2, and IL6. This was shown to be independent of IRF1, IRF3, or p65, canonical transcription factors necessary for activation of both type I and III interferon promoters. The mechanism of DNA-PKcs to restrict ZIKV infection is independent of DSB. Thus, these data suggest a non-canonical role for DNA-PK during Zika virus infection, acting downstream of IFNs transcription factors for an efficient antiviral immune response.


Subject(s)
Zika Virus Infection , Zika Virus , Infant, Newborn , Animals , Humans , Zika Virus/physiology , Virus Replication , Interferons/pharmacology , Antiviral Agents/therapeutic use , DNA
7.
Microbiol Spectr ; 9(2): e0117921, 2021 10 31.
Article in English | MEDLINE | ID: mdl-34643412

ABSTRACT

Conjugated linoleic acid (CLA) has been the subject of numerous studies in recent decades because of its associated health benefits. CLA is an intermediate product of the biohydrogenation pathway of linoleic acid (LA) in bacteria. Several bacterial species capable of efficiently converting LA into CLA have been widely reported in the literature, among them Lactobacillus delbrueckii subsp. bulgaricus LBP UFSC 2230. Over the last few years, a multicomponent enzymatic system consisting of three enzymes involved in the biohydrogenation process of LA has been proposed. Sequencing the genome of L. delbrueckii subsp. bulgaricus LBP UFSC 2230 revealed only one gene capable of encoding an oleate hydratase (OleH), unlike the presence of multiple genes typically found in similar strains. This study investigated the biological effect of the OleH enzyme of L. delbrueckii subsp. bulgaricus LBP UFSC 2230 on the hydration of LA and dehydration of ricinoleic acid (RA) and its possible role in the production of CLA. The OleH was cloned, expressed, purified, and characterized. Fatty acid measurements were made by an internal standard method using a gas chromatography-coupled flame ionization detector (GC-FID) system. It was found that the enzyme is a hydratase/dehydratase, leading to a reversible transformation between LA and RA. In addition, the results showed that L. delbrueckii subsp. bulgaricus LBP UFSC 2230 OleH protein plays a role in stress tolerance in Escherichia coli. In conclusion, the OleH of L. delbrueckii subsp. bulgaricus LBP UFSC 2230 catalyzes the initial stage of saturation metabolism of LA, although it has not converted the substrates directly into CLA. IMPORTANCE This study provides insight into the enzymatic mechanism of CLA synthesis in L. delbrueckii subsp. bulgaricus and broadens our understanding of the bioconversion of LA and RA by OleH. The impact of OleH on the production of the c9, t11 CLA isomer and stress tolerance by E. coli has been assisted. The results provide an understanding of the factors which influence OleH activity. L. delbrueckii subsp. bulgaricus LBP UFSC 2230 OleH presented two putative fatty acid-binding sites. Recombinant OleH catalyzed both LA hydration and RA dehydration. OleH was shown to play a role in bacterial growth performance in the presence of LA.


Subject(s)
Hydro-Lyases/metabolism , Lactobacillus delbrueckii/enzymology , Lactobacillus delbrueckii/metabolism , Linoleic Acid/metabolism , Ricinoleic Acids/metabolism , Genome, Bacterial/genetics , Hydro-Lyases/genetics , Hydrogenation , Lactobacillus delbrueckii/genetics , Stress, Physiological/physiology , Whole Genome Sequencing
8.
Eur J Anaesthesiol ; 38(5): 524-533, 2021 05 01.
Article in English | MEDLINE | ID: mdl-33259449

ABSTRACT

BACKGROUND: The effect of dexmedetomidine on Nociception Level Index-guided (Medasense, Israel) antinociception to reduce intra-operative opioid requirements has not been previously investigated. OBJECTIVE: We aimed to determine if low-dose dexmedetomidine would reduce remifentanil requirements during Nociception Level Index-guided antinociception without increasing complications associated with dexmedetomidine. DESIGN: Double-blind randomised controlled trial. SETTING: Two university teaching hospitals in Brussels, Belgium. PATIENTS: American Society of Anesthesiologists 1 and 2 patients (n = 58) undergoing maxillofacial or cervicofacial surgery under propofol--remifentanil target-controlled infusion anaesthesia. INTERVENTIONS: A 30 min infusion of dexmedetomidine, or equal volume of 0.9% NaCl, was infused at 1.2 µg kg-1 h-1 immediately preceding induction and then decreased to 0.6 µg kg-1 h-1 until 30 min before ending surgery. Nociception Level Index and frontal electroencephalogram guided the remifentanil and propofol infusions, respectively. MAIN OUTCOMES: The primary outcome was the remifentanil requirement. Other outcomes included the propofol requirement, cardiovascular status and postoperative outcome. RESULTS: Mean ±â€ŠSD remifentanil (3.96 ±â€Š1.95 vs. 4.42 ±â€Š2.04 ng ml-1; P = 0.0024) and propofol (2.78 ±â€Š1.36 vs. 3.06 ±â€Š1.29 µg ml-1; P = 0.0046) TCI effect site concentrations were lower in the dexmedetomidine group at 30 min postincision and remained lower throughout surgery. When remifentanil (0.133 ±â€Š0.085 vs. 0.198 ±â€Š0.086 µg kg-1 min-1; P = 0.0074) and propofol (5.7 ±â€Š2.72 vs. 7.4 ±â€Š2.80 mg kg-1 h-1; P = 0.0228) requirements are represented as infusion rates, this effect became statistically significant at 2 h postincision. CONCLUSION: In ASA 1 and 2 patients receiving Nociception Level Index-guided antinociception, dexmedetomidine decreases intra-operative remifentanil requirements. Combined frontal electroencephalogram and Nociception Level Index monitoring can measure dexmedetomidine's hypnotic and opioid-sparing effects during remifentanil-propofol target-controlled infusion anaesthesia. TRIAL REGISTRATIONS: Clinicaltrials.gov: NCT03912740, EudraCT: 2018-004512-22.


Subject(s)
Dexmedetomidine , Propofol , Anesthetics, Intravenous , Belgium , Humans , Nociception , Remifentanil
9.
Intensive Care Med ; 46(5): 973-982, 2020 05.
Article in English | MEDLINE | ID: mdl-32052069

ABSTRACT

PURPOSE: The aim of this study was to assess the neurologic outcome following extracorporeal cardiopulmonary resuscitation (ECPR) in five European centers. METHODS: Retrospective database analysis of prospective observational cohorts of patients undergoing ECPR (January 2012-December 2016) was performed. The primary outcome was 3-month favorable neurologic outcome (FO), defined as the cerebral performance categories of 1-2. Survival to ICU discharge and the number of patients undergoing organ donation were secondary outcomes. A subgroup of patients with stringent selection criteria (i.e., age ≤ 65 years, witnessed bystander CPR, no major co-morbidity and ECMO implemented within 1 h from arrest) was also analyzed. RESULTS: A total of 423 patients treated with ECPR were included (median age 57 [48-65] years; male gender 78%); ECPR was initiated for OHCA in 258 (61%) patients. Time from arrest to ECMO implementation was 65 [48-84] min. Eighty patients (19%) had favorable neurological outcome. ICU survival was 24% (n = 102); 23 (5%) non-survivors underwent organ donation procedures. Favorable neurological outcome rate was lower (9% vs. 34%, p < 0.01) in out-of-hospital than in-hospital cardiac arrest and was significantly associated with shorter time from collapse to ECMO. The application of stringent ECPR criteria (n = 105) resulted in 38% of patients with favorable neurologic outcome. CONCLUSIONS: ECPR was associated with intact neurological recovery in 19% of unselected cardiac arrest victims, with 38% favorable outcome if stringent selection criteria would have been applied.


Subject(s)
Cardiopulmonary Resuscitation , Extracorporeal Membrane Oxygenation , Out-of-Hospital Cardiac Arrest , Aged , Humans , Male , Middle Aged , Out-of-Hospital Cardiac Arrest/therapy , Retrospective Studies , Treatment Outcome
10.
Elife ; 82019 10 22.
Article in English | MEDLINE | ID: mdl-31637998

ABSTRACT

Monocyte counts are increased during human tuberculosis (TB) but it has not been determined whether Mycobacterium tuberculosis (Mtb) directly regulates myeloid commitment. We demonstrated that exposure to Mtb directs primary human CD34+ cells to differentiate into monocytes/macrophages. In vitro myeloid conversion did not require type I or type II IFN signaling. In contrast, Mtb enhanced IL-6 responses by CD34+ cell cultures and IL-6R neutralization inhibited myeloid differentiation and decreased mycobacterial growth in vitro. Integrated systems biology analysis of transcriptomic, proteomic and genomic data of large data sets of healthy controls and TB patients established the existence of a myeloid IL-6/IL6R/CEBP gene module associated with disease severity. Furthermore, genetic and functional analysis revealed the IL6/IL6R/CEBP gene module has undergone recent evolutionary selection, including Neanderthal introgression and human pathogen adaptation, connected to systemic monocyte counts. These results suggest Mtb co-opts an evolutionary recent IFN-IL6-CEBP feed-forward loop, increasing myeloid differentiation linked to severe TB in humans.


Subject(s)
CCAAT-Enhancer-Binding Proteins/metabolism , Interferons/metabolism , Interleukin-6/metabolism , Monocytes/metabolism , Mycobacterium tuberculosis/immunology , Tuberculosis/immunology , Antigens, CD34 , CCAAT-Enhancer-Binding Proteins/genetics , Cell Differentiation , Cell Proliferation , Cytokines/genetics , Cytokines/metabolism , Genome-Wide Association Study , Humans , Hydrolases , Interferons/genetics , Interleukin-6/genetics , Macrophages/microbiology , Monocytes/microbiology , Mycobacterium tuberculosis/pathogenicity , Myeloid Cells/physiology , Proteomics , Receptors, Interleukin-6 , Severity of Illness Index , Transcriptome , Tuberculosis/metabolism
11.
Crit Care ; 23(1): 27, 2019 Jan 28.
Article in English | MEDLINE | ID: mdl-30691512

ABSTRACT

BACKGROUND: The potential benefit of extracorporeal cardiopulmonary resuscitation (ECPR) compared to conventional CPR (CCPR) for patients with refractory cardiac arrest (CA) remains unclear. METHODS: This study is a retrospective analysis of a prospective database of CA patients, which includes all consecutive adult patients admitted to the Department of Intensive Care after CA between January 2012 and December 2017. The decision to initiate ECPR was made by the attending physician and ECPR performed by the ECPR team, which is composed of ICU physicians. A propensity score was derived using a logistic regression model, including characteristics that varied between groups with a p <  0.10 and were potentially related to outcome. Primary outcomes were survival to ICU discharge and favorable 3-month neurologic outcome, assessed by a Cerebral Performance Category (CPC) score of 1-2. RESULTS: From a total of 635 patients with CA during the study period (ECPR, n = 112), 80 ECPR patients were matched to 80 CCPR patients. The time from arrest to termination of CPR (i.e., return of spontaneous circulation [ROSC], extracorporeal membrane oxygenation [ECMO] initiation, or death) was 54 ± 22 and 54 ± 19 min in the ECPR and CCPR groups, respectively. ROSC rates were 77/80 (96%) for ECPR and 30/80 (38%) for CCPR (p <  0.001). Survival to ICU discharge was 18/80 (23%) vs. 14/80 (18%) in the ECPR and CCPR groups, respectively (p = 0.42). At 3 months, 17/80 (21%) ECPR patients and 9/80 (11%) CCPR patients had a favorable outcome (p = 0.11). Cox regression analysis stratified by matched pairs showed a significantly higher neurologic outcome rate in the ECPR group than in the CCPR group (log-rank test p = 0.003). CONCLUSIONS: ECPR after CA may be associated with improved long-term neurological outcome.


Subject(s)
Cardiopulmonary Resuscitation/standards , Extracorporeal Membrane Oxygenation/standards , Adult , Aged , Female , Humans , Logistic Models , Male , Middle Aged , Out-of-Hospital Cardiac Arrest/therapy , Propensity Score , Prospective Studies , Retrospective Studies , Time Factors , Treatment Outcome
12.
J Immunol ; 200(4): 1434-1442, 2018 02 15.
Article in English | MEDLINE | ID: mdl-29311364

ABSTRACT

IFN-stimulated gene 15 (ISG15) deficiency in humans leads to severe IFNopathies and mycobacterial disease, the latter being previously attributed to its extracellular cytokine-like activity. In this study, we demonstrate a novel role for secreted ISG15 as an IL-10 inducer, unique to primary human monocytes. A balanced ISG15-induced monocyte/IL-10 versus lymphoid/IFN-γ expression, correlating with p38 MAPK and PI3K signaling, was found using targeted in vitro and ex vivo systems analysis of human transcriptomic datasets. The specificity and MAPK/PI3K-dependence of ISG15-induced monocyte IL-10 production was confirmed in vitro using CRISPR/Cas9 knockout and pharmacological inhibitors. Moreover, this ISG15/IL-10 axis was amplified in leprosy but disrupted in human active tuberculosis (TB) patients. Importantly, ISG15 strongly correlated with inflammation and disease severity during active TB, suggesting its potential use as a biomarker, awaiting clinical validation. In conclusion, this study identifies a novel anti-inflammatory ISG15/IL-10 myeloid axis that is disrupted in active TB.


Subject(s)
Cytokines/immunology , Interleukin-10/immunology , Leukocytes, Mononuclear/immunology , Tuberculosis/immunology , Ubiquitins/immunology , Humans
13.
Sci Rep ; 6: 36339, 2016 11 02.
Article in English | MEDLINE | ID: mdl-27805018

ABSTRACT

Targeting regions of proteins that show a high degree of structural conservation has been proposed as a method of developing immunotherapies and vaccines that may bypass the wide genetic variability of RNA viruses. Despite several attempts, a vaccine that protects evenly against the four circulating Dengue virus (DV) serotypes remains elusive. To find critical conserved amino acids in dengue viruses, 120 complete genomes of each serotype were selected at random and used to calculate conservation scores for nucleotide and amino acid sequences. The identified peptide sequences were analysed for their structural conservation and localisation using crystallographic data. The longest, surface exposed, highly conserved peptide of Envelope protein was found to correspond to amino acid residues 250 to 270. Mutation of this peptide in DV1 was lethal, since no replication of the mutant virus was detected in human cells. Antibodies against this peptide were detected in DV naturally infected patients indicating its potential antigenicity. Hence, this study has identified a highly conserved, critical peptide in DV that is a target of antibodies in infected humans.


Subject(s)
Dengue Virus/genetics , Dengue Virus/immunology , Dengue/immunology , Peptides/immunology , Viral Envelope Proteins/genetics , Amino Acid Sequence , Antibodies, Viral/metabolism , Base Sequence , Conserved Sequence , Crystallography, X-Ray , Dengue/virology , Genome, Viral , Humans , Models, Molecular , Mutation , Peptides/chemistry , Peptides/genetics , Protein Conformation , Serogroup , Viral Envelope Proteins/chemistry , Viral Envelope Proteins/immunology
14.
Hepatology ; 61(1): 348-60, 2015 Jan.
Article in English | MEDLINE | ID: mdl-24824608

ABSTRACT

UNLABELLED: Drug-induced liver injury (DILI) is an important cause of acute liver failure, with limited therapeutic options. During DILI, oncotic necrosis with concomitant release and recognition of intracellular content amplifies liver inflammation and injury. Among these molecules, self-DNA has been widely shown to trigger inflammatory and autoimmune diseases; however, whether DNA released from damaged hepatocytes accumulates into necrotic liver and the impact of its recognition by the immune system remains elusive. Here we show that treatment with two different hepatotoxic compounds (acetaminophen and thioacetamide) caused DNA release into the hepatocyte cytoplasm, which occurred in parallel with cell death in vitro. Administration of these compounds in vivo caused massive DNA deposition within liver necrotic areas, together with an intravascular DNA coating. Using confocal intravital microscopy, we revealed that liver injury due to acetaminophen overdose led to a directional migration of neutrophils to DNA-rich areas, where they exhibit an active patrolling behavior. DNA removal by intravenous DNASE1 injection or ablation of Toll-like receptor 9 (TLR9)-mediated sensing significantly reduced systemic inflammation, liver neutrophil recruitment, and hepatotoxicity. Analysis of liver leukocytes by flow cytometry revealed that emigrated neutrophils up-regulated TLR9 expression during acetaminophen-mediated necrosis, and these cells sensed and reacted to extracellular DNA by activating the TLR9/NF-κB pathway. Likewise, adoptive transfer of wild-type neutrophils to TLR9(-/-) mice reversed the hepatoprotective phenotype otherwise observed in TLR9 absence. CONCLUSION: Hepatic DNA accumulation is a novel feature of DILI pathogenesis. Blockage of DNA recognition by the innate immune system may constitute a promising therapeutic venue.


Subject(s)
Chemical and Drug Induced Liver Injury/immunology , Chemical and Drug Induced Liver Injury/metabolism , DNA/metabolism , Hepatocytes/drug effects , Liver/drug effects , Acetaminophen/adverse effects , Analgesics, Non-Narcotic/adverse effects , Animals , Hepatocytes/metabolism , Liver/metabolism , Mice, Inbred C57BL , Neutrophil Activation , Neutrophils/drug effects , Neutrophils/metabolism , Toll-Like Receptor 9/metabolism
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