Exogenous Interleukin-10 versus Glucocorticoids: Effect on Gene Expression and Pro-inflammatory Cytokine Release in Polymorphonuclear Leukocytes and Monocytes of the Newborn
ABSTRACT: INTRODUCTION: Persistent lung inflammation, with an influx of polymorphonuclear leukocytes and monocytes, occurs early in bronchopulmonary dysplasia. We hypothesized that: 1) that interleukin-10, a potent anti-inflammatory cytokine, would cause a markedly different gene expression profile compared to dexamethasone in these cells, and 2) monocyte insensitivity to dexamethasone was related to glucocorticoid receptor expression. RESULTS: For polymorphonuclear leukocytes, there were <20% of genes changing expression in common between interleukin-10 and dexamethasone. The monocyte had 5 times the number of genes changing expression with interleukin-10 compared to the polymorphonuclear leukocyte. Dexamethasone, in the therapeutic range, had no effect on gene expression in monocytes. The order of potency for inhibition of interleukin-8 release from monocytes was IL-10>betamethasone>> dexamethasone and hydrocortisone. Glucocorticoid potency was directly related to the degree of glucocorticoid receptor translocation to the monocyte nucleus. DISCUSSION: Gene expression profiles by IL-10 versus dexamethasone indicates that there may be major differences in efficacy and adverse effects if interleukin-10 is used for therapy in the future. Betamethasone may be a better therapeutic choice than dexamethasone. METHODS: Isolated cord blood cells were pre-incubated with anti-inflammatory agents prior to endotoxin stimulation. Measurements were made by microarrays, RT-qPCR, ELISA, and Western blots. Isolation of cord blood polymorphonuclear leukocytes and monocytes separately from 5 subjects. Endotoxin stimulation in cell culture for 4 hours. Comparison of gene expression between endotoxin alone versus endotoxin-stimualted cells pretreated with interleukin-10 or dexamethasone (at equimolar, therapeutic levels, 10-8 M. Cell Types : MONOs, PMNs; Treatments: LPS, LPS+IL-10, LPS+DEX
Project description:Introduction: Increasing evidence now supports the association between the fetal inflammatory response syndrome (FIRS) with the pathogenesis of preterm labor, intraventricular hemorrhage and bronchopulmonary dysplasia. These disorders are among the most important causes of mortality and morbidity in the perinatal period. During the fetal inflammatory response syndrome (FIRS) polymorphonuclear leukocytes (PMNs) and monocytes (MONOs) are sequentially recruited into the placenta; the same process occurs in the lung of the newborn during the development of bronchopulmonary dysplasia (BPD). The aim of the study was to reveal cell-specific differences in gene expression and cytokine release in response to endotoxin that would elucidate inflammatory control mechanisms in the newly born. Results: Compared to PMNs, MONOs had a greater diversity and more robust expression of pro-inflammatory (PI) gene expression at 4h. Only MONOs had genes changing expression in the JAK/STAT pathway including interleukin-10. Isolation of cord blood polymorphonuclear leukocytes and monocytes separately from 5 subjects. Endotoxin stimulation in cell culture for 4 hours. Comparison of gene expression between PBS versus endotoxin (LPS).
Project description:Monocyte exposure to lipopolysaccharide (LPS) induces a transient state in which these cells are refractory to further endotoxin stimulation. Here we demonstrate the transcriptome analysis of in vitro generated LPS refractory monocytes upon subsequent re-exposure to LPS for different time points. Overall design: Total RNA obtained from human monocyte exposure treated with LPS for 3h, 6h, or 24h, subsequent to endotoxin tolerization or not.
Project description:Monocyte exposure to lipopolysaccharide (LPS) induces a transient state in which these cells are refractory to further endotoxin stimulation. Here we demonstrate the transcriptome analysis of in vitro generated LPS refractory monocytes upon subsequent re-exposure to LPS for different time points. Total RNA obtained from human monocyte exposure treated with LPS for 3h, 6h, or 24h, subsequent to endotoxin tolerization or not.
Project description:We analyzed the delayed LPS-induced expression pattern in monocytes. Activation of monocytes by microbial products is an important mechanism contributing to host protection against invading pathogens. This process has to be tightly controlled to ensure that antimicrobial response does not result in fatal host tissue damage. Therefore we investigated control mechanisms during prolonged monocyte activation by bacterial endotoxin. Overall design: We performed a genome-wide analysis of lipopolysaccharide (LPS)-triggered expression profile in monocytes after 4 hours and 16 hours. To identify destinct delayed LPS-induced expression pattern we compared these both expression profiles.
Project description:Objective: Postnatal glucocorticoids (GCs) are widely used in the prevention of chronic lung disease in premature infants. However, their use is associated with neurodevelopmental delay and cerebral palsy. We hypothesized that postnatal dexamethasone or betamethasone in high-dose, but not low-dose, would induce hypomyelination, astrogliosis, and motor impairment in premature rabbit pups. Additionally, these effects would be mediated by glucocorticoid receptors (GRs). Methods: Preterm rabbit pups, delivered by C-section at E29 (term=32d), were treated with a high dose of dexamethasone or vehicle. Myelin basic protein (MBP), glial fibrillary basic protein (GFAP), oligodendrocyte proliferation and maturation, and alteration of transcriptomic profile were evaluated in these pups. Neurobehavioral assessments were performed at 14d. Results: High-dose dexamethasone treatment reduced MBP expression and induced motor-impairment compared with controls. High-dose dexamethasone induced astrogliosis and altered genes associated with myelination, cell-cycle, GR, and MAP-Kinase signaling. Interpretation: High-dose postnatal dexamethasone arrested maturation of oligodendrocytes, and induced hypomyelination, gliosis and motor deficits. GC treatment reduced myelination by genomic GR-dependent mechanisms, and caused astrogliosis by non-genomic mechanisms. Two-condition experiment: forebrains of HDD (high dose dexamethasone) vs. CTR (PBS) post-natally expossed rabbit pups. Biological replicates: 4 CTR replicates, 4 HDD replicates.
Project description:In this study, we compared human monocytes treated with GM-CSF, M-CSF, dexamethosone or in combination with dexamethasone. A comparison of the different monocyte populations was made using microarray profiling.
Project description:Diversity of biological molecules in newborn and adult immune cells contributes to differences in cell function and atopic properties. Micro RNAs (miRNAs) are reported involve in the regulation of immune system. Therefore, determining the miRNA expression profile of leukocyte sub-populations is important for understanding immune system regulation. In order to explore the unique microRNA profiling that contribute to altered immune in neonates, we comprehensively analyzed the functional miRNA signatures of eight leukocyte subsets (polymorphonuclear cells, monocytes, CD4+ T cells, CD8+ T cells, natural killer cells, B cells, plasmacytoid dendritic cells (pDCs), and myeloid dendritic cells (mDCs)) from both neonatal and adult umbilical cord and peripheral blood samples, respectively. We observed distinct miRNA profiles between adult and neonatal blood leukocyte subsets, including unique miRNA signatures for each cell lineage. Leukocyte miRNA signatures were altered after stimulation. Adult peripheral leukocytes had higher let-7b-5p expression levels compared to neonatal cord leukocytes across multiple subsets, irrespective of stimulation. Transfecting neonatal monocytes with a let-7b-5p mimic resulted in a reduction of LPS-induced IL-6 and TNF-a production, while transfection of a let-7b-5p inhibitor into adult monocytes enhanced IL-6 and TNF-a production. With this functional approach, we provide intact differential microRNA expression profiling of specific immune cell subsets between neonates and adults. These studies serve as a basis to further understand the altered immune response observed in neonates and advance the development of therapeutic strategies Overall design: we set out to comprehensively analyze the miRNA expression signatures of eight leukocyte subsets (polymorphonuclear cells (PMNs), monocytes, CD4+ T cells, CD8+ T cells natural killer (NK) cells, B cells, pDCs, and myeloid dendritic cells (mDCs)) between neonatal and adult samples.
Project description:This study explored how chronic stress influences the activity of signaling pathways that regulate inflammation in the human monocyte transcriptome. The sample consisted of 33 adults caring for a family member with glioblastoma, a terminal brain cancer, and 47 control subjects whose lives were free of major stressors. The subjects were assessed on four occasions across an eight-month period. Relative to controls, caregivers’ monocytes showed increased expression of genes bearing response elements for nuclear-factor kappa B, a key pro-inflammatory transcription factor in monocytes. Simultaneously, caregivers showed reduced expression of genes with response elements for the glucocorticoid receptor, a transcription factor that conveys anti-inflammatory signals to monocytes. These transcriptional disparities were not attributable to demographic or behavioral confounds. They also were not attributable to differences in diurnal cortisol output, or the abundance of glucocorticoid receptor expressed by monocytes. In ex vivo studies of monocytes stimulated with the bacterial product lipopolysaccharide, caregivers showed increased production of the pro-inflammatory cytokine interleukin-6, and were less sensitive to cortisol-mediated inhibition of this response. These findings suggest a scenario wherein chronic stressors engender functional changes that hamper monocytes’ capacity to transduce cortisol’s anti-inflammatory signals. These changes occur in parallel with, and perhaps enable, greater inflammatory signaling via nuclear-factor kappa B. The resulting inflammatory milieu could serve as a pathogenic mechanism through which chronic stressors like caregiving accentuate vulnerability to later health problems. series type: Risk prediction Individual differences in basal leukocyte gene expression profiles as a function of chronic caregiving stress Characteristics included in statistical analyses of gene expression data are provided in each sample records. Please note that educational attainment is scored as following; 0=less than high school, 1=high school diploma or equivalent, 2=associate's degree, 3=bachelor's degree, 4=masters degree, 5=doctoral degree