The Relationship of Circulatory miRNA-21 Expression with IL-15 Level in Celiac Disease Patients in Karbala Province

Background: Celiac disease (CeD) (celiac sprue) is a condition of immune-mediated disorder characterized by inflammation of the small intestine as a result of gluten protein ingestion in susceptible patients (HLA-DQ2/DQ8 positivity). MicroRNAs (miRNAs) are a type of ribonucleic acids presented as small non-coding single-chain ribonucleic acids, which hinder different types of messenger RNAs (mRNAs) translation, hence silencing their target genes. Upregulation of miRNA expression and its role in immune system is contributed to a wide range of diseases. Objectives: Evaluating the level of miRNA-21 and its relation to the proinflammatory cytokine (IL-15) in CeD patients, and determine their role as biomarkers for disease diagnosis. Materials and Methods: A total of 100 patients of both genders and various ages diagnosed positively with CeD who attended the OesophagoGastroDuodenoscopy unit. The patients included both males and females of different ages. Their biopsy results were confirmed with serological testing. In addition, this study included 100 participants who were in good health as control group. Results: CeD is more common in females (60%) than in males (40%). ELISA was used to measure the concentration of IL-15 in CeD patients which was significantly higher in about (10.100 ng/mL), while the control group recorded (0.365 ng/mL) ( P ≤ 0.001). The expression of miRNA-21 was very highly statistically significant up regulated in CeD patients compared to control ( P ≤ 0.001). Receiver operating characteristic curve (ROC) measurement as follows: cutoff value was 8.763, area under the curve 0.922, sensitivity 0.922%, specificity 0.955%, and (CI 95% 0.453–0.814). Conclusion: IL-15 levels are higher in CeD patients which can be considered as a hallmark for CeD diagnosis. miRNA-21 expression was higher in CeD patients, the ROC curve was done for miRNA-21 in serum for early diagnosis of the disease because it shows good sensitivity and specificity. Finally, these results revealed that IL-15 and miRNA-21 can be a promising biomarker for CeD diagnosis.