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The Lancet. Infectious Diseases May 2017Listeriosis is a severe foodborne infection and a notifiable disease in France. We did a nationwide prospective study to characterise its clinical features and... (Observational Study)
Observational Study
BACKGROUND
Listeriosis is a severe foodborne infection and a notifiable disease in France. We did a nationwide prospective study to characterise its clinical features and prognostic factors.
METHODS
MONALISA was a national prospective observational cohort study. We enrolled eligible cases declared to the National Reference Center for Listeria (all microbiologically proven) between Nov 3, 2009, and July 31, 2013, in the context of mandatory reporting. The outcomes were analysis of clinical features, characterisation of Listeria isolates, and determination of predictors of 3-month mortality or persisting impairment using logistic regression. A hierarchical clustering on principal components was also done for neurological and bacteraemic cases. The study is registered at ClinicalTrials.gov, number NCT01520597.
FINDINGS
We enrolled 818 cases from 372 centres, including 107 maternal-neonatal infections, 427 cases of bacteraemia, and 252 cases of neurolisteriosis. Only five (5%) of 107 pregnant women had an uneventful outcome. 26 (24%) of 107 mothers experienced fetal loss, but never after 29 weeks of gestation or beyond 2 days of admission to hospital. Neurolisteriosis presented as meningoencephalitis in 212 (84%) of 252 patients; brainstem involvement was only reported in 42 (17%) of 252 patients. 3-month mortality was higher for bacteraemia than neurolisteriosis (hazard ratio [HR] 0·54 [95% CI 0·41-0·69], p<0·0001). For both bacteraemia and neurolisteriosis, the strongest mortality predictors were ongoing cancer (odds ratio [OR] 5·19 [95% CI 3·01-8·95], p<0·0001), multi-organ failure (OR 7·98 [4·32-14·72], p<0·0001), aggravation of any pre-existing organ dysfunction (OR 4·35 [2·79-6·81], p<0·0001), and monocytopenia (OR 3·70 [1·82-7·49], p=0·0003). Neurolisteriosis mortality was higher in blood-culture positive patients (OR 3·67 [1·60-8·40], p=0·002) or those receiving adjunctive dexamethasone (OR 4·58 [1·50-13·98], p=0·008).
INTERPRETATION
The severity of listeriosis is higher than reported elsewhere. We found evidence of a significantly reduced survival in patients with neurolisteriosis treated with adjunctive dexamethasone, and also determined the time window for fetal losses. MONALISA provides important new data to improve management and predict outcome in listeriosis.
FUNDING
Programme Hospitalier Recherche Clinique, Institut Pasteur, Inserm, French Public Health Agency.
Topics: Adult; Aged; Bacteremia; Female; Foodborne Diseases; France; Hospitalization; Humans; Infant, Newborn; Infant, Newborn, Diseases; Infectious Disease Transmission, Vertical; Listeria monocytogenes; Listeriosis; Male; Mandatory Reporting; Meningoencephalitis; Population Surveillance; Pregnancy; Pregnancy Complications, Infectious; Prognosis; Prospective Studies; Risk Factors
PubMed: 28139432
DOI: 10.1016/S1473-3099(16)30521-7 -
International Journal of Molecular... Jun 2019The PI3K/Akt pathway plays a crucial role in the survival, proliferation, and migration of macrophages, which may impact the development of atherosclerosis. Changes in... (Review)
Review
The PI3K/Akt pathway plays a crucial role in the survival, proliferation, and migration of macrophages, which may impact the development of atherosclerosis. Changes in Akt isoforms or modulation of the Akt activity levels in macrophages significantly affect their polarization phenotype and consequently atherosclerosis in mice. Moreover, the activity levels of Akt signaling determine the viability of monocytes/macrophages and their resistance to pro-apoptotic stimuli in atherosclerotic lesions. Therefore, elimination of pro-apoptotic factors as well as factors that antagonize or suppress Akt signaling in macrophages increases cell viability, protecting them from apoptosis, and this markedly accelerates atherosclerosis in mice. In contrast, inhibition of Akt signaling by the ablation of Rictor in myeloid cells, which disrupts mTORC2 assembly, significantly decreases the viability and proliferation of blood monocytes and macrophages with the suppression of atherosclerosis. In addition, monocytes and macrophages exhibit a threshold effect for Akt protein levels in their ability to survive. Ablation of two Akt isoforms, preserving only a single Akt isoform in myeloid cells, markedly compromises monocyte and macrophage viability, inducing monocytopenia and diminishing early atherosclerosis. These recent advances in our understanding of Akt signaling in macrophages in atherosclerosis may have significant relevance in the burgeoning field of cardio-oncology, where PI3K/Akt inhibitors being tested in cancer patients can have significant cardiovascular and metabolic ramifications.
Topics: Animals; Apoptosis; Atherosclerosis; Blood Cells; Cell Survival; Humans; Macrophage Activation; Macrophages; Phosphatidylinositol 3-Kinases; Protein Isoforms; Proto-Oncogene Proteins c-akt; Signal Transduction
PubMed: 31159424
DOI: 10.3390/ijms20112703 -
Nature Immunology Jun 2022Hypoxemia is a defining feature of acute respiratory distress syndrome (ARDS), an often-fatal complication of pulmonary or systemic inflammation, yet the resulting...
Hypoxemia is a defining feature of acute respiratory distress syndrome (ARDS), an often-fatal complication of pulmonary or systemic inflammation, yet the resulting tissue hypoxia, and its impact on immune responses, is often neglected. In the present study, we have shown that ARDS patients were hypoxemic and monocytopenic within the first 48 h of ventilation. Monocytopenia was also observed in mouse models of hypoxic acute lung injury, in which hypoxemia drove the suppression of type I interferon signaling in the bone marrow. This impaired monopoiesis resulted in reduced accumulation of monocyte-derived macrophages and enhanced neutrophil-mediated inflammation in the lung. Administration of colony-stimulating factor 1 in mice with hypoxic lung injury rescued the monocytopenia, altered the phenotype of circulating monocytes, increased monocyte-derived macrophages in the lung and limited injury. Thus, tissue hypoxia altered the dynamics of the immune response to the detriment of the host and interventions to address the aberrant response offer new therapeutic strategies for ARDS.
Topics: Animals; Humans; Hypoxia; Inflammation; Lung; Lung Injury; Mice; Respiratory Distress Syndrome
PubMed: 35624205
DOI: 10.1038/s41590-022-01216-z -
The Journal of Experimental Medicine Jul 2017In humans, the monocyte pool comprises three subsets (classical, intermediate, and nonclassical) that circulate in dynamic equilibrium. The kinetics underlying their...
In humans, the monocyte pool comprises three subsets (classical, intermediate, and nonclassical) that circulate in dynamic equilibrium. The kinetics underlying their generation, differentiation, and disappearance are critical to understanding both steady-state homeostasis and inflammatory responses. Here, using human in vivo deuterium labeling, we demonstrate that classical monocytes emerge first from marrow, after a postmitotic interval of 1.6 d, and circulate for a day. Subsequent labeling of intermediate and nonclassical monocytes is consistent with a model of sequential transition. Intermediate and nonclassical monocytes have longer circulating lifespans (∼4 and ∼7 d, respectively). In a human experimental endotoxemia model, a transient but profound monocytopenia was observed; restoration of circulating monocytes was achieved by the early release of classical monocytes from bone marrow. The sequence of repopulation recapitulated the order of maturation in healthy homeostasis. This developmental relationship between monocyte subsets was verified by fate mapping grafted human classical monocytes into humanized mice, which were able to differentiate sequentially into intermediate and nonclassical cells.
Topics: Animals; Bone Marrow Cells; Cell Differentiation; Cell Survival; Cells, Cultured; Deuterium; Endotoxemia; Flow Cytometry; Homeostasis; Humans; Inflammation; Isotope Labeling; Mice; Monocytes; Time Factors
PubMed: 28606987
DOI: 10.1084/jem.20170355 -
Hematology/oncology Clinics of North... Aug 2018GATA2 deficiency is an immunodeficiency and bone marrow failure disorder caused by pathogenic variants in GATA2. It is inherited in an autosomal-dominant pattern or can... (Review)
Review
GATA2 deficiency is an immunodeficiency and bone marrow failure disorder caused by pathogenic variants in GATA2. It is inherited in an autosomal-dominant pattern or can be due to de novo sporadic germline mutation. Patients commonly have B-cell, dendritic cell, natural killer cell, and monocytopenias, and are predisposed to myelodysplastic syndrome, acute myeloid leukemia, and chronic myelomonocytic leukemia. Patients may suffer from disseminated human papilloma virus and mycobacterial infections, pulmonary alveolar proteinosis, and lymphedema. The bone marrow eventually takes on a characteristic hypocellular myelodysplasia with loss of monocytes and hematogones, megakaryocytes with separated nuclear lobes, micromegakaryocytes, and megakaryocytes with hypolobated nuclei.
Topics: Anemia, Aplastic; Bone Marrow Diseases; Bone Marrow Failure Disorders; GATA2 Deficiency; GATA2 Transcription Factor; Genetic Predisposition to Disease; Germ-Line Mutation; Hemoglobinuria, Paroxysmal; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Leukemia, Myeloid, Acute; Myelodysplastic Syndromes
PubMed: 30047422
DOI: 10.1016/j.hoc.2018.04.004 -
Journal of Clinical Immunology Aug 2019WHIM syndrome is a rare combined primary immunodeficiency disease named by acronym for the diagnostic tetrad of warts, hypogammaglobulinemia, infections, and... (Review)
Review
WHIM syndrome is a rare combined primary immunodeficiency disease named by acronym for the diagnostic tetrad of warts, hypogammaglobulinemia, infections, and myelokathexis. Myelokathexis is a unique form of non-cyclic severe congenital neutropenia caused by accumulation of mature and degenerating neutrophils in the bone marrow; monocytopenia and lymphopenia, especially B lymphopenia, also commonly occur. WHIM syndrome is usually caused by autosomal dominant mutations in the G protein-coupled chemokine receptor CXCR4 that impair desensitization, resulting in enhanced and prolonged G protein- and β-arrestin-dependent responses. Accordingly, CXCR4 antagonists have shown promise as mechanism-based treatments in phase 1 clinical trials. This review is based on analysis of all 105 published cases of WHIM syndrome and covers current concepts, recent advances, unresolved enigmas and controversies, and promising future research directions.
Topics: Adaptive Immunity; Alleles; Combined Modality Therapy; Diagnosis, Differential; Disease Management; Disease Susceptibility; Genetic Association Studies; Genetic Predisposition to Disease; Humans; Immunity, Innate; Mutation; Phenotype; Precision Medicine; Primary Immunodeficiency Diseases; Warts
PubMed: 31313072
DOI: 10.1007/s10875-019-00665-w -
Cells Jun 2021Cell death mechanisms are crucial to maintain an appropriate environment for the functionality of healthy cells. However, during viral infections, dysregulation of these... (Review)
Review
Cell death mechanisms are crucial to maintain an appropriate environment for the functionality of healthy cells. However, during viral infections, dysregulation of these processes can be present and can participate in the pathogenetic mechanisms of the disease. In this review, we describe some features of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and some immunopathogenic mechanisms characterizing the present coronavirus disease (COVID-19). Lymphopenia and monocytopenia are important contributors to COVID-19 immunopathogenesis. The fine mechanisms underlying these phenomena are still unknown, and several hypotheses have been raised, some of which assign a role to cell death as far as the reduction of specific types of immune cells is concerned. Thus, we discuss three major pathways such as apoptosis, necroptosis, and pyroptosis, and suggest that all of them likely occur simultaneously in COVID-19 patients. We describe that SARS-CoV-2 can have both a direct and an indirect role in inducing cell death. Indeed, on the one hand, cell death can be caused by the virus entry into cells, on the other, the excessive concentration of cytokines and chemokines, a process that is known as a COVID-19-related cytokine storm, exerts deleterious effects on circulating immune cells. However, the overall knowledge of these mechanisms is still scarce and further studies are needed to delineate new therapeutic strategies.
Topics: Apoptosis; COVID-19; Cell Death; Cytokine Release Syndrome; Cytokines; Humans; Necroptosis; SARS-CoV-2; Virus Internalization
PubMed: 34201847
DOI: 10.3390/cells10071585 -
EMBO Molecular Medicine Oct 2020Early in the COVID-19 pandemic, type 2 diabetes (T2D) was marked as a risk factor for severe disease and mortality. Inflammation is central to the aetiology of both... (Observational Study)
Observational Study
Early in the COVID-19 pandemic, type 2 diabetes (T2D) was marked as a risk factor for severe disease and mortality. Inflammation is central to the aetiology of both conditions where variations in immune responses can mitigate or aggravate disease course. Identifying at-risk groups based on immunoinflammatory signatures is valuable in directing personalised care and developing potential targets for precision therapy. This observational study characterised immunophenotypic variation associated with COVID-19 severity in T2D. Broad-spectrum immunophenotyping quantified 15 leucocyte populations in peripheral circulation from a cohort of 45 hospitalised COVID-19 patients with and without T2D. Lymphocytopenia and specific loss of cytotoxic CD8 lymphocytes were associated with severe COVID-19 and requirement for intensive care in both non-diabetic and T2D patients. A morphological anomaly of increased monocyte size and monocytopenia restricted to classical CD14 CD16 monocytes was specifically associated with severe COVID-19 in patients with T2D requiring intensive care. Increased expression of inflammatory markers reminiscent of the type 1 interferon pathway (IL6, IL8, CCL2, INFB1) underlaid the immunophenotype associated with T2D. These immunophenotypic and hyperinflammatory changes may contribute to increased voracity of COVID-19 in T2D. These findings allow precise identification of T2D patients with severe COVID-19 as well as provide evidence that the type 1 interferon pathway may be an actionable therapeutic target for future studies.
Topics: Aged; COVID-19; Chemokine CCL2; Diabetes Mellitus, Type 2; Female; Humans; Immunophenotyping; Inflammation; Interleukin-6; Leukocytes, Mononuclear; Lipopolysaccharide Receptors; Lymphopenia; Male; Middle Aged; Monocytes; Risk Factors; SARS-CoV-2; Severity of Illness Index
PubMed: 32816392
DOI: 10.15252/emmm.202013038