scholarly journals Global Modulation in DNA Epigenetics during Pro-Inflammatory Macrophage Activation

2019 ◽  
Author(s):  
Nikhil Jain ◽  
Tamar Shahal ◽  
Tslil Gabrieli ◽  
Noa Gilat ◽  
Dmitry Torchinsky ◽  
...  

AbstractDNA methylation patterns create distinct gene expression profiles. These patterns are maintained after cell division, thus enabling the differentiation and maintenance of multiple cell types from the same genome sequence. The advantage of this mechanism for transcriptional control is that chemical-encoding allows to rapidly establish new epigenetic patterns “on-demand” through enzymatic methylation and de-methylation of DNA. Here we show that this feature is associated with the fast response of macrophages during their pro-inflammatory activation. By using a combination of mass spectroscopy and single-molecule imaging to quantify global epigenetic changes in the genomes of primary macrophages, we followed three distinct DNA marks (methylated, hydroxymethylated and unmethylated), involved in establishing new DNA methylation patterns during pro-inflammatory activation. The observed epigenetic modulation together with gene expression data generated for the involved enzymatic machinery, may suggest that de-methylation upon LPS-activation starts with oxidation of methylated CpGs, followed by excision-repair of these oxidized bases and their replacement with unmodified cytosine.

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 596-596 ◽  
Author(s):  
Dominique Jpm Stumpel ◽  
Pauline Schneider ◽  
Eddy HJ van Roon ◽  
Judith M Boer ◽  
Renee X Menezes ◽  
...  

Abstract At present, long-term survival rates in childhood acute lymphoblastic leukemia (ALL) easily exceed 80%. However, the prognosis for infants (<1 year) with ALL barely reaches 50%. Infant ALL is characterized by chromosomal translocations involving the Mixed Lineage Leukemia (MLL) gene that occur in about 80% of the cases. The most frequent MLL translocations in infant ALL include t(4;11), t(11;19) and t(9;11). In about 20% of the infant ALL cases no MLL rearrangements are observed. Recent gene-expression profiling characterized MLL-rearranged ALL as a unique type of leukemia, that is genetically clearly separable from other ALL subtypes. As epigenetic modifications affect gene-expression, we hypothesized that the specific gene-expression profiles associated with MLL-rearranged ALL may well be driven by epigenetic changes. The best-studied epigenetic event in hematological malignancies constitutes the transcriptional silencing of (tumor suppressor) genes by promoter CpG island hypermethylation. To explore the DNA methylation patterns underlying MLL-rearranged infant ALL, we applied Differential Methylation Hybridization (DMH) using both 9k (Huang, 2002) and 244k CpG island microarrays (Agilent) on primary infant ALL samples carrying t(4;11) (n=21), t(11;19) (n=17), t(9;11) (n=6) or wild-type MLL genes (n=13). The resulting DNA methylation patterns were compared with the patterns found in healthy pediatric bone marrow samples (n=8). In addition, relapse material from three infants with MLL-rearranged ALL was included and compared with the corresponding patient sample obtained at diagnosis. Both CpG island microarray platforms demonstrate that t(4;11) and t(11;19) characterize extensively hypermethylated leukemias, whereas t(9;11)-positive and translocation-negative infant ALL epigenetically resemble normal bone marrow. When the CpG array data (Agilent) were compared with available gene expression profiles (Affymetrix), we found that 95% of the genes from the top 100 of genes most significantly hypermethylated in t(4;11)- or t(11;19)-positive infant ALL were indeed down-regulated. Using the t(4;11)-positive cell line models SEMK2 and RS4;11, we demonstrate that the majority of these hypermethylated genes could be demethylated by the demethylating agent zebularine. Among t(4;11)- and t(11;19)-positive infant ALL samples, two subgroups could be identified displaying either more or less pronounced methylation patterns. Heavy methylation appeared to be associated with a significantly reduced relapse-free survival (p=0.03). Encouraged by these data, we analyzed relapse samples from t(4;11)- and t(11;19)-positive infant ALL patients, and found that these samples were even more extensively hypermethylated than the corresponding initial infant ALL samples. We here present, for the first time to our knowledge, a global view of the methylome in infant patients with MLL-rearranged ALL. We demonstrate that severe promoter CpG hypermethylation is present in t(4;11)- and t(11;19)-positive infant ALL. Of main therapeutic interest is our finding that the degree of DNA methylation among t(4;11)- and t(11;19)-positive infant ALL patients is related to relapse-free survival. Therefore, MLL-rearranged infant ALL patients with heavily methylated leukemias in particular should be considered candidates for therapies including inhibitors of DNA methylation in order to reverse the malignant phenotypes of these leukemias, and improve prognosis. Since MLL-rearranged infant ALL patients are even more hypermethylated at relapse, inhibition of aberrant DNA methylation might also be of vital importance at this stage of disease. Based on these data, we propose to initiate clinical trials using demethylating agents for patients with relapsed MLL- rearranged infant ALL. Meanwhile, we are investigating the in vitro cytotoxicity of various demethylating agents in our laboratory to pave the way for future clinical trials.


2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Katherine R. Dobbs ◽  
Paula Embury ◽  
Emmily Koech ◽  
Sidney Ogolla ◽  
Stephen Munga ◽  
...  

Abstract Background Age-related changes in adaptive and innate immune cells have been associated with a decline in effective immunity and chronic, low-grade inflammation. Epigenetic, transcriptional, and functional changes in monocytes occur with aging, though most studies to date have focused on differences between young adults and the elderly in populations with European ancestry; few data exist regarding changes that occur in circulating monocytes during the first few decades of life or in African populations. We analyzed DNA methylation profiles, cytokine production, and inflammatory gene expression profiles in monocytes from young adults and children from western Kenya. Results We identified several hypo- and hyper-methylated CpG sites in monocytes from Kenyan young adults vs. children that replicated findings in the current literature of differential DNA methylation in monocytes from elderly persons vs. young adults across diverse populations. Differentially methylated CpG sites were also noted in gene regions important to inflammation and innate immune responses. Monocytes from Kenyan young adults vs. children displayed increased production of IL-8, IL-10, and IL-12p70 in response to TLR4 and TLR2/1 stimulation as well as distinct inflammatory gene expression profiles. Conclusions These findings complement previous reports of age-related methylation changes in isolated monocytes and provide novel insights into the role of age-associated changes in innate immune functions.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Bing He ◽  
Ping Chen ◽  
Sonia Zambrano ◽  
Dina Dabaghie ◽  
Yizhou Hu ◽  
...  

AbstractMolecular characterization of the individual cell types in human kidney as well as model organisms are critical in defining organ function and understanding translational aspects of biomedical research. Previous studies have uncovered gene expression profiles of several kidney glomerular cell types, however, important cells, including mesangial (MCs) and glomerular parietal epithelial cells (PECs), are missing or incompletely described, and a systematic comparison between mouse and human kidney is lacking. To this end, we use Smart-seq2 to profile 4332 individual glomerulus-associated cells isolated from human living donor renal biopsies and mouse kidney. The analysis reveals genetic programs for all four glomerular cell types (podocytes, glomerular endothelial cells, MCs and PECs) as well as rare glomerulus-associated macula densa cells. Importantly, we detect heterogeneity in glomerulus-associated Pdgfrb-expressing cells, including bona fide intraglomerular MCs with the functionally active phagocytic molecular machinery, as well as a unique mural cell type located in the central stalk region of the glomerulus tuft. Furthermore, we observe remarkable species differences in the individual gene expression profiles of defined glomerular cell types that highlight translational challenges in the field and provide a guide to design translational studies.


2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A4-A4
Author(s):  
Anushka Dikshit ◽  
Dan Zollinger ◽  
Karen Nguyen ◽  
Jill McKay-Fleisch ◽  
Kit Fuhrman ◽  
...  

BackgroundThe canonical WNT-β-catenin signaling pathway is vital for development and tissue homeostasis but becomes strongly tumorigenic when dysregulated. and alter the transcriptional signature of a cell to promote malignant transformation. However, thorough characterization of these transcriptomic signatures has been challenging because traditional methods lack either spatial information, multiplexing, or sensitivity/specificity. To overcome these challenges, we developed a novel workflow combining the single molecule and single cell visualization capabilities of the RNAscope in situ hybridization (ISH) assay with the highly multiplexed spatial profiling capabilities of the GeoMx™ Digital Spatial Profiler (DSP) RNA assays. Using these methods, we sought to spatially profile and compare gene expression signatures of tumor niches with high and low CTNNB1 expression.MethodsAfter screening 120 tumor cores from multiple tumors for CTNNB1 expression by the RNAscope assay, we identified melanoma as the tumor type with the highest CTNNB1 expression while prostate tumors had the lowest expression. Using the RNAscope Multiplex Fluorescence assay we selected regions of high CTNNB1 expression within 3 melanoma tumors as well as regions with low CTNNB1 expression within 3 prostate tumors. These selected regions of interest (ROIs) were then transcriptionally profiled using the GeoMx DSP RNA assay for a set of 78 genes relevant in immuno-oncology. Target genes that were differentially expressed were further visualized and spatially assessed using the RNAscope Multiplex Fluorescence assay to confirm GeoMx DSP data with single cell resolution.ResultsThe GeoMx DSP analysis comparing the melanoma and prostate tumors revealed that they had significantly different gene expression profiles and many of these genes showed concordance with CTNNB1 expression. Furthermore, immunoregulatory targets such as ICOSLG, CTLA4, PDCD1 and ARG1, also demonstrated significant correlation with CTNNB1 expression. On validating selected targets using the RNAscope assay, we could distinctly visualize that they were not only highly expressed in melanoma compared to the prostate tumor, but their expression levels changed proportionally to that of CTNNB1 within the same tumors suggesting that these differentially expressed genes may be regulated by the WNT-β-catenin pathway.ConclusionsIn summary, by combining the RNAscope ISH assay and the GeoMx DSP RNA assay into one joint workflow we transcriptionally profiled regions of high and low CTNNB1 expression within melanoma and prostate tumors and identified genes potentially regulated by the WNT- β-catenin pathway. This novel workflow can be fully automated and is well suited for interrogating the tumor and stroma and their interactions.GeoMx Assays are for RESEARCH ONLY, not for diagnostics.


Author(s):  
Ana M. Sotoca ◽  
Michael Weber ◽  
Everardus J. J. van Zoelen

Human mesenchymal stem cells have a high potential in regenerative medicine. They can be isolated from a variety of adult tissues, including bone marrow, and can be differentiated into multiple cell types of the mesodermal lineage, including adipocytes, osteocytes, and chondrocytes. Stem cell differentiation is controlled by a process of interacting lineage-specific and multipotent genes. In this chapter, the authors use full genome microarrays to explore gene expression profiles in the process of Osteo-, Adipo-, and Chondro-Genic lineage commitment of human mesenchymal stem cells.


2020 ◽  
Vol 11 ◽  
Author(s):  
Nitish Kumar Mishra ◽  
Meng Niu ◽  
Siddesh Southekal ◽  
Prachi Bajpai ◽  
Amr Elkholy ◽  
...  

2019 ◽  
Vol 20 (12) ◽  
pp. 3073 ◽  
Author(s):  
Ana Dienstbier ◽  
Fabian Amman ◽  
Daniel Štipl ◽  
Denisa Petráčková ◽  
Branislav Večerek

Bordetella pertussis is a Gram-negative strictly human pathogen of the respiratory tract and the etiological agent of whooping cough (pertussis). Previously, we have shown that RNA chaperone Hfq is required for virulence of B. pertussis. Furthermore, microarray analysis revealed that a large number of genes are affected by the lack of Hfq. This study represents the first attempt to characterize the Hfq regulon in bacterial pathogen using an integrative omics approach. Gene expression profiles were analyzed by RNA-seq and protein amounts in cell-associated and cell-free fractions were determined by LC-MS/MS technique. Comparative analysis of transcriptomic and proteomic data revealed solid correlation (r2 = 0.4) considering the role of Hfq in post-transcriptional control of gene expression. Importantly, our study confirms and further enlightens the role of Hfq in pathogenicity of B. pertussis as it shows that Δhfq strain displays strongly impaired secretion of substrates of Type III secretion system (T3SS) and substantially reduced resistance to serum killing. On the other hand, significantly increased production of proteins implicated in transport of important metabolites and essential nutrients observed in the mutant seems to compensate for the physiological defect introduced by the deletion of the hfq gene.


2020 ◽  
Vol 7 (5) ◽  
pp. 881-896 ◽  
Author(s):  
Dongxu He ◽  
Aiqin Mao ◽  
Chang-Bo Zheng ◽  
Hao Kan ◽  
Ka Zhang ◽  
...  

Abstract The aorta, with ascending, arch, thoracic and abdominal segments, responds to the heartbeat, senses metabolites and distributes blood to all parts of the body. However, the heterogeneity across aortic segments and how metabolic pathologies change it are not known. Here, a total of 216 612 individual cells from the ascending aorta, aortic arch, and thoracic and abdominal segments of mouse aortas under normal conditions or with high blood glucose levels, high dietary salt, or high fat intake were profiled using single-cell RNA sequencing. We generated a compendium of 10 distinct cell types, mainly endothelial (EC), smooth muscle (SMC), stromal and immune cells. The distributions of the different cells and their intercommunication were influenced by the hemodynamic microenvironment across anatomical segments, and the spatial heterogeneity of ECs and SMCs may contribute to differential vascular dilation and constriction that were measured by wire myography. Importantly, the composition of aortic cells, their gene expression profiles and their regulatory intercellular networks broadly changed in response to high fat/salt/glucose conditions. Notably, the abdominal aorta showed the most dramatic changes in cellular composition, particularly involving ECs, fibroblasts and myeloid cells with cardiovascular risk factor-related regulons and gene expression networks. Our study elucidates the nature and range of aortic cell diversity, with implications for the treatment of metabolic pathologies.


2005 ◽  
Vol 73 (4) ◽  
pp. 2327-2335 ◽  
Author(s):  
Yumiko Hosogi ◽  
Margaret J. Duncan

ABSTRACT Porphyromonas gingivalis, a gram-negative oral anaerobe, is strongly associated with adult periodontitis. The adherence of the organism to host epithelium signals changes in both cell types as bacteria initiate infection and colonization and epithelial cells rally their defenses. We hypothesized that the expression of a defined set of P. gingivalis genes would be consistently up-regulated during infection of HEp-2 human epithelial cells. P. gingivalis genome microarrays were used to compare the gene expression profiles of bacteria that adhered to HEp-2 cells and bacteria that were incubated alone. Genes whose expression was temporally up-regulated included those involved in the oxidative stress response and those encoding heat shock proteins that are essential to maintaining cell viability under adverse conditions. The results suggest that contact with epithelial cells induces in P. gingivalis stress-responsive pathways that promote the survival of the bacterium.


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