24 research outputs found
The role of nerve growth factor in neuropeptide up-regulation in trigeminal ganglia neurons following irritant exposure.
Workers exposed to occupational irritants often develop symptoms of airway inflammation by unknown mechanisms. In laboratory animals, occupational irritants activate sensory nerves located in airway walls. Sensory nerves respond by increasing neuropeptide production. The neuropeptide, substance P (SP), is produced in trigeminal ganglia (TG) cell bodies and released from nasal mucosa nerve endings. Neurogenic inflammation results from the release of neuropeptides and is characterized by vasodilation, plasma extravasation, mucous secretion and neutrophil chemotaxis. The purpose of these studies was to characterize the regulation of neuropeptides in the upper airway after irritant exposure. Nasal irritation to asphalt fumes is a commonly reported symptom among road crew workers. In the first study, rats chronically exposed to asphalt fumes had increased levels of neuropeptides in TG neurons innervating the nasal epithelium and increased inflammatory cells in their nasal cavities. The enhanced neuropeptide production and subsequent neurogenic inflammation may cause symptoms of nasal irritation in road workers exposed to asphalt fumes. Since exposure to airway irritants has health implications that may be related to increased neuropeptide production, the remaining studies investigated mechanisms regulating SP production. Nerve growth factor is believed to mediate the irritant induced up-regulation of SP. Increased NGF levels in the nasal cavity preceded the up-regulation of SP in TG neurons innervating the nasal epithelium following TDI exposure. NGF binds receptors on sensory nerve terminals and travels to cell bodies where it regulates SP production. This temporal relationship suggests that irritant-induced SP expression in sensory neurons maybe mediated by NGF. To prove that NGF mediates SP production following irritant exposure, compounds were administered prior to TDI exposure to block NGF activity. K252a, a non-specific tyrosine-kinase inhibitor, prevented the increase in SP production and the inflammatory cell influx. The final study used an in vivo and ex vivo approach to demonstrate that NGF is synthesized and released from the nasal mucosa and the release of NGF increases following TDI exposure. Therefore, these studies support the concept that NGF release from the nasal mucosa following TDI correlates with SP production in TG cell bodies
Energy, gender and development: what are the linkages ? where is the evidence ?
This report reviews the literature on the links between energy access, welfare, and gender in order to provide evidence on where gender considerations in the energy sector matter and how they might be addressed. Prepared as a background document for the 2012 World Development Report on Gender Equality and Development, and part of the Social Development Department's ongoing work on gender and infrastructure, the report describes and evaluates the evidence on the links between gender and energy focusing on: increased access to woodfuel through planting of trees and forest management; improved cooking technologies; and access to electricity and motive energy. The report's main finding is that energy interventions can have significant gender benefits, which can be realized via careful design and targeting of interventions based on a context-specific understanding of energy scarcity and household decision-making, in particular how women's preferences, opportunity cost of time, and welfare are reflected in household energy decisions. The report focuses on the academic peer-reviewed literature and, although it applies fairly inclusive screening criteria when selecting the evidence to consider, finds that the evidence on many of the energy-gender linkages is often limited. There is thus a clear need for studies to evaluate interventions and identify key design elements for gender-sensitive project design.
Effects of bone marrowâderived mesenchymal stromal cells on gene expression in human alveolar type II cells exposed to TNFâα, ILâ1ÎČ, and IFNâÎł
The acute respiratory distress syndrome (ARDS) is common in critically ill patients and has a high mortality rate. Mesenchymal stromal cells (MSCs) have demonstrated therapeutic potential in animal models of ARDS, and their benefits occur in part through interactions with alveolar type II (ATII) cells. However, the effects that MSCs have on human ATII cells have not been well studied. Using previously published microarray data, we performed genomeâwide differential gene expression analyses of human ATII cells that were (1) unstimulated, (2) exposed to proinflammatory cytokines (CytoMix), or (3) exposed to proinflammatory cytokines plus MSCs. Findings were validated by qPCR. Alveolar type II cells differentially expressed hundreds of genes when exposed either to proinflammatory cytokines or to proinflammatory cytokines plus MSCs. Stimulation with proinflammatory cytokines increased expression of inflammatory genes and downregulated genes related to surfactant function and alveolar fluid clearance. Some of these changes, including expression of some cytokines and genes related to surfactant, were reversed by exposure to MSCs. In addition, MSCs induced upregulation of other potentially beneficial genes, such as those related to extracellular matrix remodeling. We confirmed several of these gene expression changes by qPCR. Thus, ATII cells downregulate genes associated with surfactant and alveolar fluid clearance when exposed to inflammatory cytokines, and mesenchymal stromal cells partially reverse many of these gene expression changes.Mesenchymal stromal cells (MSCs) have therapeutic potential for the acute respiratory distress syndrome, and their benefits occur in part through interactions with alveolar type II (ATII) cells. We performed genomeâwide differential gene expression analyses of human ATII cells that were (1) unstimulated, (2) exposed to proinflammatory cytokines (CytoMix), or (3) exposed to CytoMix plus MSCs. Stimulation with CytoMix increased expression of inflammatory genes and downregulated genes related to surfactant function and alveolar fluid clearance, and several gene expression changes were reversed by exposure to MSCs.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145579/1/phy213831_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145579/2/phy213831.pd
High-dimensional analysis reveals distinct endotypes in patients with idiopathic inflammatory myopathies
The idiopathic inflammatory myopathies (IIM) are a rare clinically heterogeneous group of conditions affecting the skin, muscle, joint, and lung in various combinations. While myositis specific autoantibodies are well described, we postulate that broader immune endotypes exist in IIM spanning B cell, T cell, and monocyte compartments. This study aims to identify immune endotypes through detailed immunophenotyping of peripheral blood mononuclear cells (PBMCs) in IIM patients compared to healthy controls. We collected PBMCs from 17 patients with a clinical diagnosis of inflammatory myositis and characterized the B, T, and myeloid cell subsets using mass cytometry by time of flight (CyTOF). Data were analyzed using a combination of the dimensionality reduction algorithm t-distributed stochastic neighbor embedding (t-SNE), cluster identification, characterization, and regression (CITRUS), and marker enrichment modeling (MEM); supervised biaxial gating validated populations identified by these methods to be differentially abundant between groups. Using these approaches, we identified shared immunologic features across all IIM patients, despite different clinical features, as well as two distinct immune endotypes. All IIM patients had decreased surface expression of RP105/CD180 on B cells and a reduction in circulating CD3+CXCR3+ subsets relative to healthy controls. One IIM endotype featured CXCR4 upregulation across all cellular compartments. The second endotype was hallmarked by an increased frequency of CD19+CD21loCD11c+ and CD3+CD4+PD1+ subsets. The experimental and analytical methods we describe here are broadly applicable to studying other immune-mediated diseases (e.g., autoimmunity, immunodeficiency) or protective immune responses (e.g., infection, vaccination)
CD19â+âCD21lo/neg cells are increased in systemic sclerosis-associated interstitial lung disease
Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017-6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD2
High-Throughput Detection of Autoantigen-Specific B Cells Among Distinct Functional Subsets in Autoimmune Donors
Antigen-specific B cells (ASBCs) can drive autoimmune disease by presenting autoantigen to cognate T cells to drive their activation, proliferation, and effector cell differentiation and/or by differentiating into autoantibody-secreting cells. Autoantibodies are frequently used to predict risk and diagnose several autoimmune diseases. ASBCs can drive type 1 diabetes even when immune tolerance mechanisms block their differentiation into antibody-secreting cells. Furthermore, anti-histidyl tRNA synthetase syndrome patients have expanded IgM+ Jo-1-binding B cells, which clinically diagnostic IgG Jo-1 autoantibodies may not fully reflect. Given the potential disconnect between the pathologic function of ASBCs and autoantibody secretion, direct study of ASBCs is a necessary step towards developing better therapies for autoimmune diseases, which often have no available cure. We therefore developed a high-throughput screening pipeline to 1) phenotypically identify specific B cell subsets, 2) expand them in vitro, 3) drive them to secrete BCRs as antibody, and 4) identify wells enriched for ASBCs through ELISA detection of antibody. We tested the capacity of several B cell subset(s) to differentiate into antibody-secreting cells following this robust stimulation. IgM+ and/or IgD+, CD27- memory, memory, switched memory, and BND B cells secreted B cell receptor (BCR) as antibody following in vitro stimulation, whereas few plasmablasts responded. Bimodal responses were observed across autoimmune donors for IgM+ CD21lo and IgM- CD21lo B cells, consistent with documented heterogeneity within the CD21lo subset. Using this approach, we detected insulin-binding B cell bias towards CD27- memory and CD27+ memory subsets in pre-symptomatic type 1 diabetes donors. We took advantage of routine detection of Jo-1-binding B cells in Jo-1+ anti-histidyl tRNA synthetase syndrome patients to show that Jo-1-binding B cells and total B cells expanded 20-30-fold using this culture system. Overall, these studies highlight technology that is amenable to small numbers of cryopreserved peripheral blood mononuclear cells that enables interrogation of phenotypic and repertoire attributes of ASBCs derived from autoimmune patients
Proinflammatory cytokines and ARDS pulmonary edema fluid induce CD40 on human mesenchymal stromal cellsâA potential mechanism for immune modulation
Risk factors for mortality and mortality rates in interstitial lung disease patients in the intensive care unit
Data on interstitial lung disease (ILD) outcomes in the intensive care unit (ICU) is of limited value due to population heterogeneity. The aim of this study was to examine risk factors for mortality and ILD mortality rates in the ICU. We performed a systematic review using five databases. 50 studies were identified and 34 were included: 17 studies on various aetiologies of ILD (mixed-ILD) and 17 on idiopathic pulmonary fibrosis (IPF). In mixed-ILD, elevated APACHE score, hypoxaemia and mechanical ventilation are risk factors for mortality. No increased mortality was found with steroid use. Evidence is inconclusive on advanced age. In IPF, evidence is inconclusive for all factors except mechanical ventilation and hypoxaemia. The overall in-hospital mortality was available in 15 studies on mixed-ILD (62% in 2001â2009 and 48% in 2010â2017) and 15 studies on IPF (79% in 1993â2004 and 65% in 2005â2017). Follow-up mortality rate at 1â
year ranged between 53% and 100%. Irrespective of ILD aetiology, mechanical ventilation is associated with increased mortality. For mixed-ILD, hypoxaemia and APACHE scores are also associated with increased mortality. IPF has the highest mortality rate among ILDs, but since 1993 the rate appears to be declining. Despite improving in-hospital survival, overall mortality remains high