scholarly journals The EBI2-oxysterol axis promotes the development of intestinal lymphoid structures and colitis

2018 ◽  
Author(s):  
Annika Wyss ◽  
Tina Raselli ◽  
Gérard Schmelczer ◽  
Glynis Klinke ◽  
Nathan Perkins ◽  
...  
Keyword(s):  
Immune System ◽  
Gene Encoding ◽  
Barr Virus ◽  
Dss Colitis ◽  
Inflammatory Bowel ◽  
Epstein Barr ◽  
Lymphoid Structures ◽  
G Protein Coupled ◽  
Colitis Model

AbstractThe gene encoding for Epstein-Barr virus-induced G-protein coupled receptor 2 (EBI2) is a risk gene for inflammatory bowel disease (IBD). Together with its oxysterol ligand 7α,25-dihydroxycholesterol, EBI2 mediates migration and differentiation of immune cells. However, the role of EBI2 in the colonic immune system remains insufficiently studied.We found increased mRNA expression of EBI2 and oxysterol synthesizing enzymes (CH25H, CYP7B1) in the inflamed colon of patients with ulcerative colitis and mice with acute or chronic dextran sulfate sodium (DSS) colitis. Accordingly, we detected elevated extraintestinal levels of 25-hydroxylated oxysterols, including 7α,25-dihydroxycholesterol in mice with acute colonic inflammation. Knockout of EBI2 or CH25H did not affect severity of DSS colitis; however, inflammation was decreased in male EBI2-/- mice in the IL-10 colitis model.The colonic immune system comprises mucosal lymphoid structures, which accumulate upon chronic inflammation in IL-10-deficient mice and in chronic DSS colitis. However, EBI2-/- mice formed significantly less colonic lymphoid structures at baseline and showed defects in inflammation-induced accumulation of lymphoid structures.In summary, we report induction of the EBI2-7α,25-dihydroxycholesterol axis in colitis and a role of EBI2 for the accumulation of lymphoid tissue during homeostasis and inflammation. These data implicate the EBI2-7α,25-dihydroxycholesterol axis in IBD pathogenesis.

Are Viruses and Parasites Linked to Celiac Disease? A Question that Still has no Definite Answer

2019 ◽  
Vol 20 (14) ◽  
pp. 1181-1193 ◽  
Author(s):  
Aref Shariati ◽  
Hamid R. Aslani ◽  
Mohammad R.H. Shayesteh ◽  
Ali Taghipour ◽  
Ahmad Nasser ◽  
...  
Keyword(s):  
Celiac Disease ◽  
Multiple Roles ◽  
Barr Virus ◽  
The People ◽  
Intestinal Infections ◽  
Inflammatory Bowel ◽  
Epstein Barr ◽  
Irritable Bowel ◽  
Related Proteins

Celiac Disease (CD) is a complex autoimmune enteropathy of the small intestine that commonly occurs in genetically predisposed individuals due to intake of gluten and related proteins. Gluten consumption, duration of breast-feeding, various infections, especially frequent intestinal infections, vaccinations and use of antibiotics can be linked to CD. It is predicted that it affects 1% of the global population and its incidence rate is increasing. Most of the people with the HLA-DQ2 or HLADQ8 are at a higher risk of developing this disease. The link between infections and autoimmune diseases has been very much considered in recent years. In several studies, we explained that pathogenic and non-pathogenic microorganisms might have multiple roles in initiation, exacerbation, and development of Irritable Bowel Syndrome (IBS) and Inflammatory Bowel Disease (IBD). In various studies, the relationship between infections caused by viruses, such as Epstein-Barr Virus (EBV), Rotavirus, Hepatitis C (HCV), Hepatitis B virus (HBV), Cytomegalovirus (CMV), and Influenza virus, and parasites including Giardia spp. and Toxoplasma gondii with CD has been raised. However, increasing evidence proposes that some of these microorganisms, especially helminths, can also have protective and even therapeutic roles in the CD process. Therefore, in order to determine the role of microorganisms in the process of this disease, we attempted to summarize the evidence suggesting the role of viral and parasitic agents in pathogenesis of CD.

scholarly journals Mesenchymal Stem Cells and Acelluar Products Attenuate Murine Induced Colitis

2020 ◽  
Author(s):  
Yan Li ◽  
Jessica Altemus ◽  
Amy L. Lightner
Keyword(s):  
Stem Cells ◽  
Mesenchymal Stem Cells ◽  
Comparative Investigation ◽  
Inflammatory Disorder ◽  
Tissue Repair And Regeneration ◽  
Dss Colitis ◽  
Cytokine Analysis ◽  
Inflammatory Bowel ◽  
Colitis Model

Abstract Background: Mesenchymal stem cells (MSCs) are a well-established immunomodulatory agent which can also promote tissue repair and regeneration. Recent studies have demonstrated MSCs as a novel therapeutic for inflammatory bowel disease (IBD), a chronic idiopathic inflammatory disorder of the gastrointestinal tract. However, the precise role of MSCs in regulating immune responses is controversial, and its significance in the pathogenesis remains IBD undefined. In addition, MSCs’ acellular product, extracellular vesicles (EVs), may also play an important role in the armamentarium of therapeutics, but how EVs compare to MSCs remains unknown due to the lack of side-by-side comparative investigation. We herein compared MSCs and MSC-derived EVs for the treatment of IBD using a DSS-induced colitis model. Methods: A DSS-induced colitis model was used. At Day 4, mice received adipose derived MSCs, MSC-derived EVs, or placebo. Weight loss, stool consistency and hematochezia was charted. At day 8, murine colons were harvested, histologic analysis performed, and serum/tissue cytokine analysis conducted. Results: MSCs and EVs demonstrated equivalent immunosuppressive function in DSS-treated mice through decreased colonic lymphocyte infiltration and attenuated disease severity after both MSC and EV treatment. Importantly, the ability to inhibit inflammation in the DSS colitis model was equivalent for both MSCs and MSC-derived EVs. Conclusions: These results suggest that (i) both MSCs and EVs are effective therapeutic candidates for a DSS-induced mouse colitis model, (ii) MSCs and EVs have similar immunosuppressive and anti-inflammatory functions, and (iii) EVs may present a novel future therapeutic for the treatment of IBD.

scholarly journals Epstein–Barr Virus DNA Exacerbates Colitis Symptoms in a Mouse Model of Inflammatory Bowel Disease

Viruses ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1272
Author(s):  
Sirine Andari ◽  
Hadi Hussein ◽  
Sukayna Fadlallah ◽  
Abdo R. Jurjus ◽  
Margret Shirinian ◽  
...  
Keyword(s):  
The Other ◽  
Colonic Disease ◽  
Barr Virus ◽  
Bowel Diseases ◽  
Proinflammatory Responses ◽  
Enhanced Expression ◽  
Inflammatory Bowel ◽  
Ebv Dna ◽  
Epstein Barr ◽  
Colitis Model

Infection with EBV has been associated with various inflammatory disorders including inflammatory bowel diseases (IBD). Contribution of this virus to intestinal disease processes has not been assessed. We previously detected that EBV DNA triggers proinflammatory responses via the activation of endosomal Toll-like receptor (TLR) signaling. Hence, to examine the colitogenic potential of EBV DNA, we used the dextran sodium sulfate (DSS) mouse colitis model. C57BL/6J mice received either DSS-containing or regular drinking water. Mice were then administered EBV DNA by rectal gavage. Administration of EBV DNA to the DSS-fed mice aggravated colonic disease activity as well as increased the damage to the colon histologic architecture. Moreover, we observed enhanced expression of IL-17A, IFNγ and TNFα in colon tissues from the colitis mice (DSS-treated) given the EBV DNA compared to the other groups. This group also had a marked decrease in expression of the CTLA4 immunoregulatory marker. On the other hand, we observed enhanced expression of endosomal TLRs in colon tissues from the EBV DNA-treated colitis mice. These findings indicate that EBV DNA exacerbates proinflammatory responses in colitis. The ubiquity of EBV in the population indicates that possible similar responses may be of pertinence in a relevant proportion of IBD patients.

scholarly journals Activation of the GPR35 pathway drives angiogenesis in the tumour microenvironment

Gut ◽  
2021 ◽  
pp. gutjnl-2020-323363
Author(s):  
Ester Pagano ◽  
Joshua E Elias ◽  
Georg Schneditz ◽  
Svetlana Saveljeva ◽  
Lorraine M Holland ◽  
...  
Keyword(s):  
Colon Cancer ◽  
Tumour Growth ◽  
Tumour Microenvironment ◽  
Tube Formation ◽  
Tissue Remodelling ◽  
Colon Cancers ◽  
Inflammatory Bowel ◽  
Ion Pumping ◽  
G Protein Coupled

ObjectivePrimary sclerosing cholangitis (PSC) is in 70% of cases associated with inflammatory bowel disease. The hypermorphic T108M variant of the orphan G protein-coupled receptor GPR35 increases risk for PSC and ulcerative colitis (UC), conditions strongly predisposing for inflammation-associated liver and colon cancer. Lack of GPR35 reduces tumour numbers in mouse models of spontaneous and colitis associated cancer. The tumour microenvironment substantially determines tumour growth, and tumour-associated macrophages are crucial for neovascularisation. We aim to understand the role of the GPR35 pathway in the tumour microenvironment of spontaneous and colitis-associated colon cancers.DesignMice lacking GPR35 on their macrophages underwent models of spontaneous colon cancer or colitis-associated cancer. The role of tumour-associated macrophages was then assessed in biochemical and functional assays.ResultsHere, we show that GPR35 on macrophages is a potent amplifier of tumour growth by stimulating neoangiogenesis and tumour tissue remodelling. Deletion of Gpr35 in macrophages profoundly reduces tumour growth in inflammation-associated and spontaneous tumour models caused by mutant tumour suppressor adenomatous polyposis coli. Neoangiogenesis and matrix metalloproteinase activity is promoted by GPR35 via Na/K-ATPase-dependent ion pumping and Src activation, and is selectively inhibited by a GPR35-specific pepducin. Supernatants from human inducible-pluripotent-stem-cell derived macrophages carrying the UC and PSC risk variant stimulate tube formation by enhancing the release of angiogenic factors.ConclusionsActivation of the GPR35 pathway promotes tumour growth via two separate routes, by directly augmenting proliferation in epithelial cells that express the receptor, and by coordinating macrophages’ ability to create a tumour-permissive environment.

scholarly journals Functions of Dendritic Cells and Its Association with Intestinal Diseases

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 583
Author(s):  
Ze-Jun Yang ◽  
Bo-Ya Wang ◽  
Tian-Tian Wang ◽  
Fei-Fei Wang ◽  
Yue-Xin Guo ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Dendritic Cells ◽  
Immune System ◽  
Regulatory Mechanism ◽  
Intestinal Tumors ◽  
Regulatory Relationship ◽  
Intestinal Diseases ◽  
Inflammatory Bowel ◽  
Plasmacytoid Dcs

Dendritic cells (DCs), including conventional DCs (cDCs) and plasmacytoid DCs (pDCs), serve as the sentinel cells of the immune system and are responsible for presenting antigen information. Moreover, the role of DCs derived from monocytes (moDCs) in the development of inflammation has been emphasized. Several studies have shown that the function of DCs can be influenced by gut microbes including gut bacteria and viruses. Abnormal changes/reactions in intestinal DCs are potentially associated with diseases such as inflammatory bowel disease (IBD) and intestinal tumors, allowing DCs to be a new target for the treatment of these diseases. In this review, we summarized the physiological functions of DCs in the intestinal micro-environment, their regulatory relationship with intestinal microorganisms and their regulatory mechanism in intestinal diseases.

scholarly journals Molecular Genetics in Epstein–Barr Virus-Associated Malignancies

Life ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 593
Author(s):  
Srikanth Umakanthan ◽  
Maryann M Bukelo
Keyword(s):  
Epstein Barr Virus ◽  
Diagnostic Tools ◽  
Main Role ◽  
Genetic Changes ◽  
Barr Virus ◽  
Cancer Pathogenesis ◽  
Genomic Studies ◽  
Epstein Barr ◽  
Oncogenic Form

Global genomic studies have detected the role of genomic alterations in the pathogenesis of Epstein–Barr virus (EBV)-associated tumors. EBV oncoproteins cause a vital shift of EBV from an infectious virus to an oncogenic form during the latent and lytic phase within the lymphoid B cells and epithelial cells. This epigenetic alteration modulates the virus and host genomes and inactivates and disrupts numerous tumor suppressors and signaling pathways. Genomic profiling has played the main role in identifying EBV cancer pathogenesis and its related targeted therapies. This article reviews the role of genetic changes in EBV-associated lymphomas and carcinomas. This includes the prolific molecular genesis, key diagnostic tools, and target-specific drugs that have been in recent clinical use.

EBV load is associated with cfDNA fragmentation and renal damage in SLE patients

Lupus ◽  
2021 ◽  
pp. 096120332110103
Author(s):  
Anna Truszewska ◽  
Agnieszka Wirkowska ◽  
Kamila Gala ◽  
Piotr Truszewski ◽  
Łucja Krzemień-Ojak ◽  
...  
Keyword(s):  
Kidney Disease ◽  
Lupus Erythematosus ◽  
Epstein Barr Virus ◽  
Renal Damage ◽  
Healthy Individuals ◽  
Pcr Assay ◽  
Barr Virus ◽  
Fragmentation Index ◽  
Epstein Barr

Background For long Epstein–Barr virus (EBV) has been suspected to be involved in the pathogenesis of systemic lupus erythematosus (SLE). The aim of this study was to verify the association between EBV, cell-free DNA (cfDNA) and kidney disease in SLE. Methods Blood samples were obtained from 43 SLE patients and 50 healthy individuals. EBV load was measured via real-time PCR assay. Sizing and quantification of plasma cfDNA was performed on Bioanalyzer. We proposed that the uniformity of cfDNA fragmentation can be described using cfDNA fragmentation index. Results SLE patients with chronic kidney disease (CKD +) had higher EBV load compared to CKD(–) patients (P = 0.042). Patients with high cfDNA level had higher EBV load (P = 0.041) and higher cfDNA fragmentation index (P < 0.001) compared to patients with low cfDNA level. Among patients with high cfDNA level, EBV load was higher in CKD(+) group compared to CKD(–) group (P = 0.035). EBV load was positively correlated with the fragmentation index in all SLE patients (P = 0.028, R2 = 0.13), and the correlation was even more pronounced in CKD (+) patients (P < 0.001, R2 = 0.20). Conclusions We showed that EBV load was associated with non-uniform cfDNA fragmentation, higher cfDNA levels, and kidney disease in SLE patients. Although the causality of this relationship could not be determined with the current study, it brings rationale for further investigations on the role of EBV and cfDNA interplay in SLE pathogenesis.

scholarly journals Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: The Human Herpesviruses Are Back!

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 185
Author(s):  
Maria Eugenia Ariza
Keyword(s):  
Chronic Fatigue Syndrome ◽  
Disease Process ◽  
Chronic Fatigue ◽  
Myalgic Encephalomyelitis ◽  
Barr Virus ◽  
Fatigue Syndrome ◽  
Specific Proteins ◽  
Epstein Barr ◽  
Human Herpesviruses

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) or Systemic Exertion Intolerance Disease (SEID) is a chronic multisystem illness of unconfirmed etiology. There are currently no biomarkers and/or signatures available to assist in the diagnosis of the syndrome and while numerous mechanisms have been hypothesized to explain the pathology of ME/CFS, the triggers and/or drivers remain unknown. Initial studies suggested a potential role of the human herpesviruses especially Epstein-Barr virus (EBV) in the disease process but inconsistent and conflicting data led to the erroneous suggestion that these viruses had no role in the syndrome. New studies using more advanced approaches have now demonstrated that specific proteins encoded by EBV could contribute to the immune and neurological abnormalities exhibited by a subgroup of patients with ME/CFS. Elucidating the role of these herpesvirus proteins in ME/CFS may lead to the identification of specific biomarkers and the development of novel therapeutics.

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