Investigating the expression level of immune system related genes IL17C, TEK and CCL4 derived from weighted gene co-expression network analysis in Alzheimer's disease

Abstract

Alzheimer's disease (AD) is the most common progressive neurodegenerative disease, the prevalence of which is increasing worldwide. So far, many studies have been conducted to regulate the expression of functional inflammatory genes, and they show that a small change can eventually cause the central nervous system to undergo pathogenic changes. IL17C, TEK, and CCL4 genes are among the genes involved in immune and inflammation pathways, and in this study, we investigate their expression level changes in peripheral blood and their relationship with AD with bioinformatics and experimental methods. Methods and Materials: Using E-MTAB-6094 microarray dataset and weighted co-expression network analysis (WGCNA), three genes IL17C, TEK and CCL4 were selected to investigate expression changes in AD. Total RNA was extracted from the peripheral blood of 50 people with AD and 50 healthy controls. The expression changes of these genes were measured using the Real-time PCR technique, and statistical analyzes of the difference in expression and Receiver Operating Characteristic (ROC) curve were performed on the resulting data. Results: The expression of IL17C was significantly decreased in Alzheimer's patients compared to the control group. On the other hand, the expression level of TEK and CCL4 increased significantly in the patient group. According to enrichment analysis, these genes are related to immune and inflammatory pathways.