Pro-inflammatory Role of Extracellular DNA in Inflammatory Bowel Disease in Children: Study of the cGAS-STING Pathway
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 40
- 试验地点
- 1
- 主要终点
- Amount of mRNA specific for colonic cGAS
研究概览
简要总结
Frequency of Inflammatory Bowel Diseases in children (IBD)-Crohn's disease (CD), Ulcerative colitis (UC) is constantly increasing. Pediatric-onset IBD represent a different nosological entity (from adult IBD) because of their major inflammatory activity, their significant anatomical extent and their stenotic and/or fistulizing character sometimes from diagnosis. Intestinal lesions are due to dysregulation of the intestinal immune system but the cause is unknown. The investigators hypothesize that extranuclear DNA participates in the amplification of the inflammatory response at the intestinal and blood levels during pediatric IBD through the cGAS-STING pathway. The investigators will analyse blood and fecal samples, and colonic biopsies issued from ill children and control participants on age of 6 to 17 years. The investigators think that this study will provide a better understanding of the mechanisms involved in pediatric IBD, assess the place of the cGAS-STING pathway, identify potential biomarkers of pediatric IBD and new potential therapeutic targets based in particular on the inhibition of the cGAS-STING pathway.
详细描述
Inflammatory Bowel Diseases in children (IBD)-Crohn's disease (CD), ulcerative colitis (UC) are severe pathology that can affect the entire digestive tract. Their annual incidence is however constantly increasing.
IBD are complex multifactorial pathologies whose cause is still unknown today. IBD occurs on a predisposing genetic background in the presence of exogenous factors and alteration of the intestinal microbiota. Intestinal lesions are due to dysregulation of the intestinal immune system with increased secretion of pro-inflammatory cytokines at the expense of anti-inflammatory cytokines.
Pediatric-onset IBD represent a different nosological entity (from adult IBD) because of their major inflammatory activity, their significant anatomical extent and their stenotic and/or fistulizing character sometimes from diagnosis. Their impact is not only individual (growth retardation, puberty delay, psychological disorders) but also family/parental, school and social. These particularities justify that biomedical research focuses on it in a more specific way.
Extracellular and extranuclear DNA (enDNA) play a major role in innate immunity by stimulating pro-inflammatory responses and activating type I interferon production. The pro-inflammatory action of enDNA is mediated by enzyme cGAS, protein STING, toll-like receptor 9 (TLR9), and the inflammasome complex NLRP3.
The investigators hypothesize that enDNA participates in the amplification of the inflammatory response at the intestinal and blood levels during pediatric IBD through the cGAS-STING pathway. They also hypothesize that there are links between the cGAS-STING pathway and other pathways involved in pediatric IBD such as NOD2 and Autophagy. The investigators will analyse blood and fecal samples, and colonic biopsies issued from ill children and controls on age of 6 to 17 years. The investigators think that this study will provide a better understanding of the mechanisms involved in pediatric IBD, assess the place of the cGAS-STING pathway, identify potential biomarkers of pediatric IBD and new potential therapeutic targets based in particular on the inhibition of the cGAS-STING pathway.
研究设计
- 研究类型
- Interventional
- 分配方式
- Na
- 干预模型
- Single Group
- 主要目的
- Health Services Research
- 盲法
- None
入排标准
- 年龄范围
- 6 Years 至 17 Years（Child）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Participants aged from 6 years inclusive to 17 years inclusive
- •Boys and girls
- •Presenting an IBD or suspicion of IBD
- •Requiring a colonoscopy for diagnosis or follow-up or other reason (abdominal pain, diarrhoea, rectal bleeding, weight loss) not confirming the diagnosis of Crohn's disease or Ulcerative Colitis
- •Active IBD if:
- •CD: PCDAI score >5 and CRP>20mg/L and faecal calprotectin> 400 µg/g
- •UC: PUCAI score>10 and faecal calprotectin>250 µg/g
- •IBD in remission if:
- •CD: PCDAI score<5 and CRP<20mg/L and faecal calprotectin<400 µg/g
- •UC: PUCAI score <10 and faecal calprotectin < 250 µg/g
- •Patients and their parents who gave their consent to participate in the study
排除标准
- •Refusal of the participant and/or one of his two parents
- •Body weight less than or equal to 20 kg
- •Blood hemoglobin level less than or equal to 9 g/dl
- •Refusal or contraindication to general anesthesia
- •Co-existing severe chronic pathology and/or treatment that could interfere with the results of the study; example: trisomy 21, treatment with growth hormone etc.
- •Protected person (under guardianship or curatorship)
- •Person under legal protection
- •Person not affiliated to a social security scheme
- •Pregnant or breastfeeding woman
研究组 & 干预措施
Patients with samples
Blood and fecal samples, and colonic biopsies will be analysed and compared between 3 groups of participants :1/ Active IBD; 2/Inactive IBD; 3/Controls "non-IBD".
干预措施: Coolonic biopsies (Procedure)
Patients with samples
Blood and fecal samples, and colonic biopsies will be analysed and compared between 3 groups of participants :1/ Active IBD; 2/Inactive IBD; 3/Controls "non-IBD".
干预措施: Blood and fecal samples (Biological)
结局指标
主要结局
Amount of mRNA specific for colonic cGAS
时间窗: Baseline
the comparison, between the 3 groups of patients, of the quantity of specific mRNA of colonic cGAS expressed as the number of "reads" during RNA sequencing (RNAseq), by a Mann-Whitney U test. It is planned from the outset to compare the groups 2 by 2, regardless of the result of an overall test such as a Kruskal-Wallis test.
次要结局
- Cytokine response(Baseline)
- Difference of DNA methylation by Methyl-Seq between the 3 groups(Baseline)
- Amount of cGAS in the cytoplasm(Baseline)
- inflammatory / dysimmune response of cytokines(Baseline)
- quantity (number of "reads") of colonic STING-specific mRNA(Baseline)
- Amount of STING in the cytoplasm(Baseline)
- quantitative difference of amount of circulating mtDNA(Baseline)
- plasma DNase activity(baseline)
- Activation (phosphorylation) of the components of the cGAS-STING pathway(Baseline)
- differences in microbial distribution(Baseline)
- extracellular DNA by qPCR(Baseline)
- Amount of nuclear DNA in teh cytoplasm(Baseline)
- Amount of colonic DNase activity(Baseline)
- Amount of mitochondrial DNA in the cytoplasm(Baseline)