Comparative Evaluation of IL-16 mRNA level and rs1131445 polymorphism of IL-16 gene in Peripheral Blood Mononuclear Cells of patients with Inflammatory Bowel Diseases

Aberrant immune response in a gene cally susceptible host is acknowledged in the pathogenesis of In ammatory Bowel Diseases (IBD) including Crohn ’ s disease (CD) and Ulcerative colitis (UC). Here we aimed to evaluate IL - 16 mRNA level, as the immune component and rs1131445 polymorphism of IL - 16 gene, as the gene c susceptibility component of IBD development in PBMC sample. A total of 97 IBD patients (13 CD and 84 UC) and 100 healthy controls were included. Peripheral Blood Mononuclear Cells (PBMCs) were extracted. Polymorphism evaluation was performed by polymerase chain reaction (PCR) followed by restriction fragment length polymorphism (RFLP) and the results were confirmed by sequencing method. Comparative Real - ti me PCR method was used for IL - 16 mRNA assessment. A 3.92 - fold increase was observed in the expression level of IL - 16 in PBMC of IBD patients compared to the controls (p<0.0001). IL - 16 expression was not signi cantly di erent in di erent IBD forms and pathological phases. Distribu on of rs1131445 polymorphism was not significantly different between controls and pa ents (P=0.825). Distribu on of CC genotype was signi cantly higher in CD patients (P=0.016). Although IL - 16 mRNA level was considerably lower in CC genotype, this difference was not statistically significant (p=0.537). Lower IL - 16 mRNA level was observed in CC genotype of rs1131445 SNP which was not in accordance with the expectations and needs to be further investigated. These data suggest that IL - 16 level could be considered as a prognostic marker in Iranian IBD patients.