Occurrence of Neutrophil Extracellular DNA Traps (NETs) in Pre-Eclampsia: A Link with Elevated Levels of Cell-Free DNA?

2006 ◽  
Vol 1075 (1) ◽  
pp. 118-122 ◽  
Author(s):  
A. GUPTA ◽  
P. HASLER ◽  
S. GEBHARDT ◽  
W. HOLZGREVE ◽  
S. HAHN
Keyword(s):  
Extracellular Dna ◽  
Cell Free Dna ◽  
Free Dna ◽  
Extracellular Dna Traps

scholarly journals Neutrophil-Extracellular Traps, Cell-Free DNA, and Immunothrombosis in Companion Animals: A Review

2019 ◽  
Vol 57 (1) ◽  
pp. 6-23 ◽  
Author(s):  
Robert Goggs ◽  
Unity Jeffery ◽  
Dana N. LeVine ◽  
Ronald H. L. Li
Keyword(s):  
Companion Animals ◽  
High Mobility ◽  
Extracellular Dna ◽  
Death Process ◽  
Cell Free Dna ◽  
Pathogen Invasion ◽  
Extracellular Traps ◽  
Trap Formation ◽  
Free Dna ◽  
Extracellular Trap

Immunothrombosis is a potentially beneficial physiological process that aids innate immunity and host defense against pathogen invasion. However, this process can also be damaging when it occurs to excess or in critical blood vessels. Formation of extracellular traps by leukocytes, particularly neutrophils, is central to our understanding of immunothrombosis. In addition to degranulation and phagocytosis, extracellular traps are the third mechanism by which neutrophils combat potential pathogens. These traps consist of extracellular DNA decorated with bactericidal cellular proteins, including elastase, myeloperoxidase, and cathepsins. Neutrophils can release these structures as part of a controlled cell-death process or via a process termed vital NETosis that enables the cells to extrude DNA but remain viable. There is accumulating evidence that NETosis occurs in companion animals, including dogs, horses, and cats, and that it actively contributes to pathogenesis. Numerous studies have been published detailing various methods for identification and quantification of extracellular trap formation, including cell-free DNA, measurements of histones and proteins such as high-mobility group box–1, and techniques involving microscopy and flow cytometry. Here, we outline the present understanding of these phenomena and the mechanisms of extracellular trap formation. We critically review the data regarding measurement of NETosis in companion animals, summarize the existing literature on NETosis in veterinary species, and speculate on what therapeutic options these insights might present to clinicians in the future.

scholarly journals Quantification of plasma cell-free DNA levels in dogs with various tumors

2019 ◽  
Vol 31 (6) ◽  
pp. 836-843 ◽  
Author(s):  
Michihito Tagawa ◽  
Genya Shimbo ◽  
Hisashi Inokuma ◽  
Kazuro Miyahara
Keyword(s):  
Disease Progression ◽  
Distant Metastasis ◽  
Malignant Tumors ◽  
Clinical Stage ◽  
Extracellular Dna ◽  
Dna Integrity ◽  
Healthy Controls ◽  
Cell Free Dna ◽  
Free Dna ◽  
Integrity Index

Circulating cell-free DNA (cfDNA) is extracellular DNA released into the bloodstream by apoptotic or necrotic tumor cells, with cfDNA determination proposed as a noninvasive, sensitive marker for the diagnosis of human cancer. We evaluated cfDNA quantification as a diagnostic and prognostic tool in dogs with various tumors. We quantified plasma cfDNA concentration by absolute real-time PCR of long interspersed nuclear elements in 50 dogs with malignant tumors, 13 dogs with benign tumors or nodules, and 11 healthy controls. Six patients with malignant tumors were followed-up, and plasma cfDNA was quantified throughout disease progression. We found that plasma cfDNA concentrations were significantly elevated in dogs with malignant tumors compared with dogs with benign nodules or healthy controls. The DNA integrity index (the ratio between long and short cfDNA fragments) was significantly lower in dogs with malignant tumors compared to healthy controls. Significantly higher cfDNA levels and a lower DNA integrity index were observed in dogs with lymphoma or leukemia, hemangiosarcoma, and distant metastasis; cfDNA levels correlated well with clinical stage and tended to increase during or before periods of disease progression, suggesting potential efficacy of cfDNA for the detection of distant metastasis and to monitor the clinical stage of neoplasia.

scholarly journals Properties and Application of Cell-Free DNA as a Clinical Biomarker

2021 ◽  
Vol 22 (17) ◽  
pp. 9110
Author(s):  
Felipe Silva de Miranda ◽  
Valério Garrone Barauna ◽  
Leandro dos Santos ◽  
Gustavo Costa ◽  
Paula Frizera Vassallo ◽  
...  
Keyword(s):  
Clinical Practice ◽  
Venous Blood ◽  
Endothelial Damage ◽  
Extracellular Dna ◽  
Release Mechanism ◽  
Blood Collection ◽  
Cell Free Dna ◽  
Molecular Features ◽  
Free Dna ◽  
Clinical Biomarker

Biomarkers are valuable tools in clinical practice. In 2001, the National Institutes of Health (NIH) standardized the definition of a biomarker as a characteristic that is objectively measured and evaluated as an indicator of normal biological processes, pathogenic processes, or pharmacological responses to a therapeutic intervention. A biomarker has clinical relevance when it presents precision, standardization and reproducibility, suitability to the patient, straightforward interpretation by clinicians, and high sensitivity and/or specificity by the parameter it proposes to identify. Thus, serum biomarkers should have advantages related to the simplicity of the procedures and to the fact that venous blood collection is commonplace in clinical practice. We described the potentiality of cfDNA as a general clinical biomarker and focused on endothelial dysfunction. Circulating cell-free DNA (cfDNA) refers to extracellular DNA present in body fluid that may be derived from both normal and diseased cells. An increasing number of studies demonstrate the potential use of cfDNA as a noninvasive biomarker to determine physiologic and pathologic conditions. However, although still scarce, increasing evidence has been reported regarding using cfDNA in cardiovascular diseases. Here, we have reviewed the history of cfDNA, its source, molecular features, and release mechanism. We also show recent studies that have investigated cfDNA as a possible marker of endothelial damage in clinical settings. In the cardiovascular system, the studies are quite new, and although interesting, stronger evidence is still needed. However, some drawbacks in cfDNA methodologies should be overcome before its recommendation as a biomarker in the clinical setting.

scholarly journals Short single-stranded DNAs with putative non-canonical structures comprise a new class of plasma cell-free DNA

BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Osamu Hisano ◽  
Takashi Ito ◽  
Fumihito Miura
Keyword(s):  
Extracellular Dna ◽  
Open Chromatin ◽  
Dna Fragments ◽  
Cell Free Dna ◽  
Dna Structures ◽  
New Class ◽  
Free Dna ◽  
G Quadruplex ◽  
Labeling Method ◽  
Library Preparation Protocol

Abstract Background Cell-free DNA (cfDNA), which is extracellular DNA present in the circulating plasma and other body fluids, is currently investigated as a minimally invasive, highly informative biomarker. While nucleosome-sized cfDNA fragments have been investigated intensively, shorter DNA fragments in the plasma have not been studied due to several technical limitations. Results We aimed to investigate the existence of shorter cfDNA fragments in the blood. Using an improved cfDNA purification protocol and a 3′-end-labeling method, we found DNA fragments of approximately 50 nucleotides in length in the human plasma, present at a molar concentration comparable to that of nucleosome-sized fragments. Unfortunately, these short fragments cannot be recovered by widely used cfDNA isolation methods. In addition, they are composed of single-stranded DNA (ssDNA), thus escaping detection in previous studies. Therefore, we established a library-preparation protocol based on our unique ssDNA ligation technique and applied it to the isolated cfDNA. Deep sequencing of these libraries revealed that the short fragments are derived from hundreds of thousands of genomic sites in open chromatin regions and enriched with transcription factor-binding sites. Remarkably, antisense strands of putative G-quadruplex motifs occupy as much as one-third of the peaks by these short fragments. Conclusions We propose a new class of plasma cfDNA composed of short single-stranded fragments that potentially form non-canonical DNA structures.

scholarly journals Delayed appearance of hypertension in spontaneously hypertensive rat (SHR) injected with CpG-rich DNA early in ontogenesis

2010 ◽  
Vol 56 (6) ◽  
pp. 686-699 ◽  
Author(s):  
N.N. Veiko ◽  
I.L. Konorova ◽  
M.E. Neverova ◽  
O.V. Fidelina ◽  
N.A. Mkrtumova ◽  
...  
Keyword(s):  
Dna Analysis ◽  
Spontaneously Hypertensive Rat ◽  
Polyclonal Antibodies ◽  
Extracellular Dna ◽  
Activity Increase ◽  
Cell Free Dna ◽  
Cpg Dna ◽  
Spontaneously Hypertensive ◽  
Free Dna ◽  
Dna Antibodies

In this study we have investigated properties of blood serum extracellular DNA (cell-free DNA) from patients with essential arterial hypertension (AH). Cell-free DNA concentration was not changed in the control AH group compared to norma (healthy donors) but fragments of CpG-rich cell-free DNA marker content were increased at transcribed area of ribosomal repeat (TArDNA, CpG-DNA). To evaluate effect of CpG-DNA on AH development in 2-day SHR line and in control normotensive line (WKY), 700 ng of human TArDNA single subcutaneous injection were inoculated to obtain anti-CpG-DNA polyclonal antibodies. These antibodies could change CpG-DNA contents in total cell-free DNA. Blood pressure (BP) in 9-week SHR line rats immunized with CpG-DNA was equal to BP of WKY rats. Then BP of immunized SHR steadily increased with age and reached high value 8 weeks later compared to control SHR rats. Cell-free DNA analysis in 17-week SHR line rats showed significantly reduced concentrations of cell-free DNA and also showed decrease in small DNA fragments content, but increased content of CpG-DNA (rat TArDNA). These changes were accompanied with 3.5-fold blood endonuclease activity increase and decrease of free (unbound to cell-free DNA) anti-CpG-DNA antibodies quantity. Total anti-CpG-DNA antibodies quantity in immunized rats wasn't changed compared to control animals. Thus, observed effect of increase in stable BP elevation age in immunized SHR line rats doesn't relate to increase of anti-CpG-DNA antibody production. Possible reason of this effect is further discussed.

scholarly journals Oxidized Extracellular DNA as a Stress Signal in Human Cells

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Aleksei V. Ermakov ◽  
Marina S. Konkova ◽  
Svetlana V. Kostyuk ◽  
Vera L. Izevskaya ◽  
Ancha Baranova ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Nuclear Translocation ◽  
Cultured Cells ◽  
Oxidative Modification ◽  
Extracellular Dna ◽  
Related Factor ◽  
Dna Fragments ◽  
Cell Free Dna ◽  
Free Dna ◽  
Stress Signal

The term “cell-free DNA” (cfDNA) was recently coined for DNA fragments from plasma/serum, while DNA present inin vitrocell culture media is known as extracellular DNA (ecDNA). Under oxidative stress conditions, the levels of oxidative modification of cellular DNA and the rate of cell death increase. Dying cells release their damaged DNA, thus, contributing oxidized DNA fragments to the pool of cfDNA/ecDNA. Oxidized cell-free DNA could serve as a stress signal that promotes irradiation-induced bystander effect. Evidence points to TLR9 as a possible candidate for oxidized DNA sensor. An exposure to oxidized ecDNA stimulates a synthesis of reactive oxygen species (ROS) that evokes an adaptive response that includes transposition of the homologous loci within the nucleus, polymerization and the formation of the stress fibers of the actin, as well as activation of the ribosomal gene expression, and nuclear translocation of NF-E2 related factor-2 (NRF2) that, in turn, mediates induction of phase II detoxifying and antioxidant enzymes. In conclusion, the oxidized DNA is a stress signal released in response to oxidative stress in the cultured cells and, possibly, in the human body; in particular, it might contribute to systemic abscopal effects of localized irradiation treatments.

scholarly journals Cell-Free DNA in Rheumatoid Arthritis

2021 ◽  
Vol 22 (16) ◽  
pp. 8941 ◽  
Author(s):  
Teppei Hashimoto ◽  
Kohsuke Yoshida ◽  
Akira Hashiramoto ◽  
Kiyoshi Matsui
Keyword(s):  
Rheumatoid Arthritis ◽  
Diagnostic Marker ◽  
Cell Damage ◽  
Extracellular Dna ◽  
Autoimmune Arthritis ◽  
Cell Free Dna ◽  
Free Dna ◽  
Pathological Conditions ◽  
Treatment Responses ◽  
Prediction Of Prognosis

Endogenous DNA derived from the nuclei or mitochondria is released into the bloodstream following cell damage or death. Extracellular DNA, called cell-free DNA (cfDNA), is associated with various pathological conditions. Recently, multiple aspects of cfDNA have been assessed, including cfDNA levels, integrity, methylation, and mutations. Rheumatoid arthritis (RA) is the most common form of autoimmune arthritis, and treatment of RA has highly varied outcomes. cfDNA in patients with RA is elevated in peripheral blood and synovial fluid and is associated with disease activity. Profiling of cfDNA in patients with RA may then be utilized in various aspects of clinical practice, such as the prediction of prognosis and treatment responses; monitoring disease state; and as a diagnostic marker. In this review, we discuss cfDNA in patients with RA, particularly the sources of cfDNA and the correlation of cfDNA with RA pathogenesis. We also highlight the potential of analyzing cfDNA profiles to guide individualized treatment approaches for RA.

scholarly journals AB0061 INVOLVEMENT OF CELL-FREE DNA IN THE DIFFERENTIATION OF OSTEOCLASTS – IMPLICATIONS FOR CLINICAL RESEARCH

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1332.1-1332
Author(s):  
P. Škubica ◽  
J. Horinkova ◽  
M. Gregová ◽  
K. Pavelka ◽  
M. Husakova ◽  
...  
Keyword(s):  
Autoimmune Diseases ◽  
Rheumatic Diseases ◽  
Extracellular Dna ◽  
Future Research ◽  
Tartrate Resistant Acid Phosphatase ◽  
Healthy Controls ◽  
Cytokine Network ◽  
Cell Free Dna ◽  
Total N ◽  
Free Dna

Background:Cell-free DNA (cfDNA) is a molecule with undisputable immunogenic potential[1]. Its role is well established in etiopathogenesis of systemic lupus erythematosus and many reports suggest it may play an important role in other rheumatic diseases[2]. Patients suffering from rheumatic diseases are at higher risk of osteoporosis[3], which may be a consequence of increased generation of osteoclasts (OC). Traditionally, increased formation of OC is attributed to changes in cytokine network[4]. It is not yet known whether cfDNA can also act on mononuclear precursors and influence their differentiation into OC.Objectives:The aim of this study was to assess role of cfDNA in differentiation of bone resorbing cells in rheumatic diseases. For this purpose, deoxyribonuclease I (DNAse) was employed to eliminate cfDNA from sera of patients and healthy controls (HC) used for cell culture.Methods:In order to evaluate effects of cfDNA on osteoclastogenesis, anin vitroexperiment of peripheral blood monocytes (PBM) cultures was designed. Axial spondyloarthritis (AxSpA) was chosen as a model of rheumatic disease. Sera of AxSpA patients (total n=13) and healthy controls (total n=13) were collected and subsequently used in cell cultures. PBM of 13 healthy donors were cultured in presence of 25 ng/ml macrophage colony-stimulating factor (M-CSF), 0,5 ng/ml receptor-activator of nuclear factor kappa B ligand (RANKL) and 10 % of pooled AxSpA or HC sera, respectively. Serum counterpart treated with DNAse was used in parallel. After 14 days, cells were stained for tartrate-resistant acid phosphatase (TRAP) and counted. TRAP positive cells with 3 or more nuclei were recognized as OC.Results:On average, differentiation of OC in presence of AxSpA sera led to higher osteoclastogenesis compared to DNAse-treated counterpart (137 vs. 61; p < 0.01). In a similar way, treatment of HC sera with DNAse greatly diminished osteoclastogenesis compared to untreated sera (17 vs. 111; p < 0.05). Overall, the effect of cfDNA depletion in HC sera regarding OC differentiation was more than 2,5× higher than the effect of cfDNA depletion in AxSpA sera (p < 0.001).Conclusion:Results of our pilot study indicate possible involvement of cfDNA in osteoclastogenesis. Decrease in number of OC after cfDNA depletion in both AxSpA sera and HC sera suggests that cfDNA effect in osteoclastogenesis is non-specific with respect to healthy condition and may represent universal link between innate immunity and bone metabolism. Lower effect of cfDNA depletion in AxSpA sera on osteoclastogenesis is very possibly owing to presence of other inflammatory molecules, which influence osteoclastogenesis. Future research might identify cfDNA as useful therapeutic target to decrease osteoporosis risk not only in patients with rheumatic and autoimmune diseases, where pathological bone resorption is imminent, but also in general aging population.References:[1]Pisetsky, D. S. (2012). The origin and properties of extracellular DNA: from PAMP to DAMP. Clinical Immunology, 144(1), 32-40.[2]Lood, C. J., & Duvvuri, B. (2019). Cell-free DNA as a biomarker in autoimmune rheumatic diseases. Frontiers in immunology, 10, 502.[3]Maruotti, N., Corrado, A., & Cantatore, F. P. (2014). Osteoporosis and rheumatic diseases. Reumatismo, 125-135.[4]Amarasekara, D. S., Yu, J., & Rho, J. (2015). Bone loss triggered by the cytokine network in inflammatory autoimmune diseases. Journal of immunology research, 2015.Acknowledgments:Project MH CR 00023728 & MEYS CR Progres Q43Disclosure of Interests:Patrik Škubica: None declared, Jana Horinkova: None declared, Monika Gregová Consultant of: Novartis, Abbvie, Paid instructor for: Novartis, Speakers bureau: Novartis, Abbvie, MSD, Karel Pavelka Consultant of: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Speakers bureau: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Marketa Husakova Speakers bureau: Novartis, Pavlina Dankova: None declared

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