scholarly journals Schistosomiasis Induces Persistent DNA Methylation and Tuberculosis-specific Immune Changes

2018 ◽  
Author(s):  
Andrew R. DiNardo ◽  
Tomoki Nishiguchi ◽  
Emily M. Mace ◽  
Kimal Rajapakshe ◽  
Godwin Mtetwa ◽  
...  

AbstractEpigenetic mechanisms, like DNA methylation, determine immune cell phenotype. To understand the epigenetic alterations induced by helminth co-infections, we evaluated the longitudinal effect of ascariasis and schistosomiasis infection on CD4+ T cell DNA methylation and the downstream tuberculosis (TB)-specific and BCG-induced immune phenotype. All experiments were performed on human primary immune cells from a longitudinal cohort of recently TB-exposed children. Compared to age-matched uninfected controls, children with active Schistosoma haematobium and Ascaris lumbricoides infection had 751 differentially DNA methylated genes with 72% hyper-methylated. Gene ontology pathway analysis identified inhibition of IFN-γ signaling, cellular proliferation, and the Th1 pathway. Targeted RT-PCR after methyl-specific endonuclease digestion confirmed DNA hyper-methylation of the transcription factors BATF3, ID2, STAT5A, IRF5, PPARg, RUNX2, IRF4 and NFATC1 and cytokines or cytokine receptors IFNGR1, TNFS11, RELT (TNF receptor), IL12RB2 and IL12B (p< 0.001; Sidak-Bonferroni). Functional blockage of the IFN-γ signaling pathway was confirmed with helminth-infected individuals having decreased up-regulation of IFN-γ-inducible genes (Mann-Whitney p < 0.05). Hypo-methylation of the IL-4 pathway and DNA hyper-methylation of the Th1 pathway was confirmed by antigen-specific multidimensional flow cytometry demonstrating decreased TB-specific IFN-γ and TNF and increased IL-4 production by CD4+ T cells (Wilcoxon signed rank P <0.05). In S.haematobium infected individuals, these DNA methylation and immune phenotypic changes persisted at least six months after successful deworming. This work demonstrates that helminth infection induces DNA methylation and immune perturbations that inhibit TB-specific immune control and that the duration of these changes are helminth-specific.

2018 ◽  
Vol 9 (1) ◽  
pp. 64-79 ◽  
Author(s):  
Gunjan Kak ◽  
Mohsin Raza ◽  
Brijendra K Tiwari

AbstractA key player in driving cellular immunity, IFN-γ is capable of orchestrating numerous protective functions to heighten immune responses in infections and cancers. It can exhibit its immunomodulatory effects by enhancing antigen processing and presentation, increasing leukocyte trafficking, inducing an anti-viral state, boosting the anti-microbial functions and affecting cellular proliferation and apoptosis. A complex interplay between immune cell activity and IFN-γ through coordinated integration of signals from other pathways involving cytokines and Pattern Recognition Receptors (PRRs) such as Interleukin (IL)-4, TNF-α, Lipopolysaccharide (LPS), Type-I Interferons (IFNS) etc. leads to initiation of a cascade of pro-inflammatory responses. Microarray data has unraveled numerous genes whose transcriptional regulation is influenced by IFN-γ. Consequently, IFN-γ stimulated cells display altered expression of many such target genes which mediate its downstream effector functions. The importance of IFN-γ is further reinforced by the fact that mice possessing disruptions in the IFN-γ gene or its receptor develop extreme susceptibility to infectious diseases and rapidly succumb to them. In this review, we attempt to elucidate the biological functions and physiological importance of this versatile cytokine. The functional implications of its biological activity in several infectious diseases and autoimmune pathologies are also discussed. As a counter strategy, many virulent pathogenic species have devised ways to thwart IFN-γ endowed immune-protection. Thus, IFN-γ mediated host-pathogen interactions are critical for our understanding of disease mechanisms and these aspects also manifest enormous therapeutic importance for the annulment of various infections and autoimmune conditions.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Chenglong You ◽  
Sijie Wu ◽  
Shijie C. Zheng ◽  
Tianyu Zhu ◽  
Han Jing ◽  
...  

Abstract Highly reproducible smoking-associated DNA methylation changes in whole blood have been reported by many Epigenome-Wide-Association Studies (EWAS). These epigenetic alterations could have important implications for understanding and predicting the risk of smoking-related diseases. To this end, it is important to establish if these DNA methylation changes happen in all blood cell subtypes or if they are cell-type specific. Here, we apply a cell-type deconvolution algorithm to identify cell-type specific DNA methylation signals in seven large EWAS. We find that most of the highly reproducible smoking-associated hypomethylation signatures are more prominent in the myeloid lineage. A meta-analysis further identifies a myeloid-specific smoking-associated hypermethylation signature enriched for DNase Hypersensitive Sites in acute myeloid leukemia. These results may guide the design of future smoking EWAS and have important implications for our understanding of how smoking affects immune-cell subtypes and how this may influence the risk of smoking related diseases.


2008 ◽  
Vol 31 (4) ◽  
pp. 11
Author(s):  
Manda Ghahremani ◽  
Courtney W Hannah ◽  
Maria Peneherrera ◽  
Karla L Bretherick ◽  
Margo R Fluker ◽  
...  

Background/Purpose: Premature ovarian failure (POF) affects 1% of women with a largely idiopathic and poorly understood etiology. The objective of this study was to identify specific epigenetic alterations by measuring DNA methylation of gene regulatory regions in women with POF vs. controls. Methods: Blood samples were collected from idiopathic POFpatients (Amenorrhea for at least 3 months and 2 serum FSH levels of > 40mIU/ml obtained > 1 month apart prior to age 40) and control women (CW) (healthy pregnancy after age 37 with out a pregnancy loss). Genomic DNA was extracted from EDTA anticoagulated blood and bisulfite converted for analysis using the Illumina Golden Gate Methylation Panel which measures DNA methylation at 1506 CpG sites in the promoter regions of 807 genes in 10 POF and 12 CW. Candidate genes with altered epigenetic marks between POF and CW at a nominal P-value < 0.05 were identified using a t-testcomparison within the Illumina bead studio software. Genes of interest were further analyzed for quantitative methylation at specific CpG sites using pyrosequencing in 30 POF and 30 CW. Results: Comparison of DNA methylation profiles of our initial POF and CW groups identified several genes with statistically significanthyper- or hypo- methylation in the POF group (P < 0.05), including the Androgen Receptor (AR)promoter region, which was significantly hypermethylated. To further validate these results, DNA methylation of the AR gene promoter was quantified bypryosequencing in a larger group of POF and CW. Pyrosequencing further confirmed a significantly higher DNA methylation of the AR promoter region inPOF vs. CW (P=0.007). Conclusions: This is a novel study identifying epigenetic alterations in POF. The hypermethylation of the AR gene in POF patients may cause decreased level of the AR in these women. This is especially interesting given a recent report of induced POF in AR deficient mice^1. Specific epigenetic markers, as identified by DNA methylation array profiling in blood, may serve as useful biomarkers for POF and other fertility disorders. However, it will need to be determined if these methylation changes are present prior to diagnosis, or are a consequence of menopause itself. Reference: 1.Hiroko S. et al. Premature ovarian failure in androgenreceptor deficient mice. PNAS;103:224-9


2020 ◽  
Vol 20 ◽  
Author(s):  
Ezzatollah Fathi ◽  
Raheleh Farahzadi ◽  
Soheila Montazersaheb ◽  
Yasin Bagheri

Background:: Epigenetic modification pattern is considered as a characteristic feature in blood malignancies. Modifications in the DNA methylation modulators are recurrent in lymphoma and leukemia, so that, the distinct methylation pattern defines different types of leukemia. Generally, the role of epigenetics is less understood and most investigations are focused on genetic abnormalities and cytogenic studies to develop novel treatments for patients with hematologic disorders. Recently, understanding the underlying mechanism of acute lymphoblastic leukemia (ALL), especially epigenetic altera-tions as a driving force in the development of ALL opens a new era of investigation for developing promising strategy, be-yond available conventional therapy. Objective:: This review will focus on a better understanding of the epigenetic mechanisms in cancer development and pro-gression, with an emphasis on epigenetic alterations in ALL including, DNA methylation, histone modification, and mi-croRNA alterations. Other topics that will be discussed include the use of epigenetic alterations as a promising therapeutic target in order to develop novel well-suited approaches against ALL. Conclusion:: According to the literature review, leukemogenesis of ALL is extensively influenced by epigenetic modifica-tions, particularly DNA hyper-methylation, histone modification, and miRNA alteration.


Author(s):  
Irfete S. Fetahu ◽  
Sabine Taschner-Mandl

AbstractNeuroblastoma (NB) is a pediatric cancer of the sympathetic nervous system and one of the most common solid tumors in infancy. Amplification of MYCN, copy number alterations, numerical and segmental chromosomal aberrations, mutations, and rearrangements on a handful of genes, such as ALK, ATRX, TP53, RAS/MAPK pathway genes, and TERT, are attributed as underlying causes that give rise to NB. However, the heterogeneous nature of the disease—along with the relative paucity of recurrent somatic mutations—reinforces the need to understand the interplay of genetic factors and epigenetic alterations in the context of NB. Epigenetic mechanisms tightly control gene expression, embryogenesis, imprinting, chromosomal stability, and tumorigenesis, thereby playing a pivotal role in physio- and pathological settings. The main epigenetic alterations include aberrant DNA methylation, disrupted patterns of posttranslational histone modifications, alterations in chromatin composition and/or architecture, and aberrant expression of non-coding RNAs. DNA methylation and demethylation are mediated by DNA methyltransferases (DNMTs) and ten-eleven translocation (TET) proteins, respectively, while histone modifications are coordinated by histone acetyltransferases and deacetylases (HATs, HDACs), and histone methyltransferases and demethylases (HMTs, HDMs). This article focuses predominately on the crosstalk between the epigenome and NB, and the implications it has on disease diagnosis and treatment.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 255
Author(s):  
Wilmer Cuervo ◽  
Lorraine M. Sordillo ◽  
Angel Abuelo

Dairy calves are unable to mount an effective immune response during their first weeks of life, which contributes to increased disease susceptibility during this period. Oxidative stress (OS) diminishes the immune cell capabilities of humans and adult cows, and dairy calves also experience OS during their first month of life. However, the impact that OS may have on neonatal calf immunity remains unexplored. Thus, we aimed to evaluate the impact of OS on newborn calf lymphocyte functions. For this, we conducted two experiments. First, we assessed the association of OS status throughout the first month of age and the circulating concentrations of the cytokines interferon-gamma (IFN-γ) and interleukin (IL) 4, as well as the expression of cytokine-encoding genes IFNG, IL2, IL4, and IL10 in peripheral mononuclear blood cells (PBMCs) of 12 calves. Subsequently, we isolated PBMCs from another 6 neonatal calves to investigate in vitro the effect of OS on immune responses in terms of activation of lymphocytes, cytokine expression, and antibody production following stimulation with phorbol 12-myristate 13-acetate or bovine herpesvirus-1. The results were compared statistically through mixed models. Calves exposed to high OS status in their first month of age showed higher concentrations of IL-4 and expression of IL4 and IL10 and lower concentrations of IFN-γ and expression of IFNG and IL2 than calves exposed to lower OS. In vitro, OS reduced lymphocyte activation, production of antibodies, and protein and gene expression of key cytokines. Collectively, our results demonstrate that OS can compromise some immune responses of newborn calves. Hence, further studies are needed to explore the mechanisms of how OS affects the different lymphocyte subsets and the potential of ameliorating OS in newborn calves as a strategy to augment the functional capacity of calf immune cells, as well as enhance calves’ resistance to infections.


Author(s):  
Tiantian Yue ◽  
Fei Sun ◽  
Faxi Wang ◽  
Chunliang Yang ◽  
Jiahui Luo ◽  
...  

AbstractThe methyl-CpG-binding domain 2 (MBD2) interprets DNA methylome-encoded information through binding to the methylated CpG DNA, by which it regulates target gene expression at the transcriptional level. Although derailed DNA methylation has long been recognized to trigger or promote autoimmune responses in type 1 diabetes (T1D), the exact role of MBD2 in T1D pathogenesis, however, remains poorly defined. Herein, we generated an Mbd2 knockout model in the NOD background and found that Mbd2 deficiency exacerbated the development of spontaneous T1D in NOD mice. Adoptive transfer of Mbd2−/− CD4 T cells into NOD.scid mice further confirmed the observation. Mechanistically, Th1 stimulation rendered the Stat1 promoter to undergo a DNA methylation turnover featured by the changes of DNA methylation levels or patterns along with the induction of MBD2 expression, which then bound to the methylated CpG DNA within the Stat1 promoter, by which MBD2 maintains the homeostasis of Th1 program to prevent autoimmunity. As a result, ectopic MBD2 expression alleviated CD4 T cell diabetogenicity following their adoptive transfer into NOD.scid mice. Collectively, our data suggest that MBD2 could be a viable target to develop epigenetic-based therapeutics against T1D in clinical settings.


RMD Open ◽  
2021 ◽  
Vol 7 (1) ◽  
pp. e001549 ◽  
Author(s):  
Aurélie Najm ◽  
Alessia Alunno ◽  
Xavier Mariette ◽  
Benjamin Terrier ◽  
Gabriele De Marco ◽  
...  

BackgroundThe SARS-CoV-2 pandemic is a global health problem. Beside the specific pathogenic effect of SARS-CoV-2, incompletely understood deleterious and aberrant host immune responses play critical roles in severe disease. Our objective was to summarise the available information on the pathophysiology of COVID-19.MethodsTwo reviewers independently identified eligible studies according to the following PICO framework: P (population): patients with SARS-CoV-2 infection; I (intervention): any intervention/no intervention; C (comparator): any comparator; O (outcome) any clinical or serological outcome including but not limited to immune cell phenotype and function and serum cytokine concentration.ResultsOf the 55 496 records yielded, 84 articles were eligible for inclusion according to question-specific research criteria. Proinflammatory cytokine expression, including interleukin-6 (IL-6), was increased, especially in severe COVID-19, although not as high as other states with severe systemic inflammation. The myeloid and lymphoid compartments were differentially affected by SARS-CoV-2 infection depending on disease phenotype. Failure to maintain high interferon (IFN) levels was characteristic of severe forms of COVID-19 and could be related to loss-of-function mutations in the IFN pathway and/or the presence of anti-IFN antibodies. Antibody response to SARS-CoV-2 infection showed a high variability across individuals and disease spectrum. Multiparametric algorithms showed variable diagnostic performances in predicting survival, hospitalisation, disease progression or severity, and mortality.ConclusionsSARS-CoV-2 infection affects both humoral and cellular immunity depending on both disease severity and individual parameters. This systematic literature review informed the EULAR ‘points to consider’ on COVID-19 pathophysiology and immunomodulatory therapies.


2014 ◽  
Vol 82 (7) ◽  
pp. 2971-2979 ◽  
Author(s):  
Roshni Rao ◽  
Prakash Nagarkatti ◽  
Mitzi Nagarkatti

ABSTRACTStaphylococcal enterotoxin B (SEB) causes food poisoning in humans. It is considered a biological weapon, and inhalation can trigger lung injury and sometimes respiratory failure. Being a superantigen, SEB initiates an exaggerated inflammatory response. While the role of microRNAs (miRNAs) in immune cell activation is getting increasing recognition, their role in the regulation of inflammatory disease induced by SEB has not been studied. In this investigation, we demonstrate that exposure to SEB by inhalation results in acute inflammatory lung injury accompanied by an altered miRNA expression profile in lung-infiltrating cells. Among the miRNAs that were significantly elevated, miR-155 was the most overexpressed. Interestingly, miR-155−/−mice were protected from SEB-mediated inflammation and lung injury. Further studies revealed a functional link between SEB-induced miR-155 and proinflammatory cytokine gamma interferon (IFN-γ). Through the use of bioinformatics tools, suppressor of cytokine signaling 1 (SOCS1), a negative regulator of IFN-γ, was identified as a potential target of miR-155. While miR-155−/−mice displayed increased expression ofSocs1, the overexpression of miR-155 led to its suppression, thereby enhancing IFN-γ levels. Additionally, the inhibition of miR-155 resulted in restoredSocs1expression. Together, our data demonstrate an important role for miR-155 in promoting SEB-mediated inflammation in the lungs throughSocs1suppression and suggest that miR-155 may be an important target in preventing SEB-mediated inflammation and tissue injury.


2021 ◽  
Vol 14 ◽  
Author(s):  
Lara J. Bou Malhab ◽  
Wael M. Abdel-Rahman

: The prevalence of obesity continues to increase to the extent that it became a worldwide pandemic. An accumulating body of evidence has associated obesity with the development of different types of cancer, including colorectal cancer, which is a notorious disease with a high mortality rate. At the molecular level, colorectal cancer is a heterogenous disease characterized by a myriad of genetic and epigenetic alterations associated with various forms of genomic instability (detailed in Supplementary Materials). Recently, the microenvironment has emerged as a major factor in carcinogenesis. Our aim is to define the different molecular alterations leading to the development of colorectal cancer in obese patients with a focus on the role of the microenvironment in carcinogenesis. We also highlight all existent molecules in clinical trials that target the activated pathways in obesity-associated colorectal cancer, whether used as single treatments or in combination. Obesity predisposes to colorectal cancer via creating a state of chronic inflammation with dysregulated adipokines, inflammatory mediators, and other factors such as immune cell infiltration. A unifying theme in obesity-mediated colorectal cancer is the activation of the PI3K/AKT, mTOR/MAPK, and STAT3 signaling pathways. Different inhibitory molecules towards these pathways exist, increasing the therapeutic choice of obesity-associated colon cancer. However, obese patients are more likely to suffer from chemotherapy overdosing. Preventing obesity through maintaining a healthy and active lifestyle remains to be the best remedy.


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