The Impact of Interleukin-21 and 23 Serum Level and Gene Expression in Celiac Disease among Sample of Iraqi Patients

Celiac disease (CD) is an autoimmune disease characterized by chronic inflammation that essentially affects the small intestine and is caused by food that contain gluten. This research aimed to explore the impact of interleukin 21 (IL-21) and interleukin 23 (IL-23) on development the Celiac disease in Iraqi patients.

Forty adults have CD were enrolled in the study with age range between 15-60 years with an average age of 36.60±2.03 years. The diagnosis of the disease was confirmed by serological examinations and intestinal endoscopy in Gastroenterology and Liver Teaching Hospital in the Medical City Hospital in Baghdad and a forty healthy subjects were included in this study as control group with age range between 16-59 years with an average age of 32.22±1.97 years. The blood serum were examined for Anti tissue transglutaminase (tTG) IgA and IgG (IgA ant-tTG and IgG ant-tTG) and anti-DGP IgA (IgA ant-DGP) antibodies as well as IL-21 and IL-23 by using enzyme-linked immunoassay technique ((ELISA). Also, the gene expression of IL-21 and IL-23 in peripheral blood of Iraqi CD patients was determined by using quantitative real-time PCR (qRT-PCR) assay.

The results showed that serum levels of anti-tTG (IgA, IgG) and anti-gliadin (IgA) antibodies were significantly higher in CD patients than in control (25.13±1.12, 19.86±1.13, and 32.01±2.36 vs. 12.62±1.04, 6.83±0.82 and 21.59±1.44 U/ml, respectively; p<0.01). In addition, IL-21 and IL-23 serum level was increased in CD patients with high significant differences (490.02±20.46 and 565.22±22.84 vs 106.87±4.23 and 256.03±13.52 pg/ml; p<0.01), respectively. The results of gene expression revealed the level of IL-21 and IL-23 was increased significantly by 3.33±0.35 and 2.83±0.27 fold change in CD patients in comparison to control.