[The expression of interferon-stimulating gene (STING/TMEM173) in liver tissue and its correlation with liver inflammation in patients with chronic hepatitis B].

Objective To investigate the relationship between the expression and distribution of interferon-stimulating gene/transmembrane protein 173(STING/TMEM173) in liver tissue and the grade of liver inflammation in patients with chronic hepatitis B, and to explore the underlying mechanisms in vitro. Methods The expression of STING/TMEM173 protein in liver tissue of 62 naive patients with chronic hepatitis B was detected by immunohistochemistry. Rank sum test and spearman correlation coefficient were used to analyze the correlation between hepatic STING/TMEM173 expression and liver inflammation grades as well as serum ALT levels. After transient or stable transfection by HBV whole genome plasmid, the expression of STING/TMEM173 in HepG2 cells was determined by Western blot analysis. The peripheral blood mononuclear cells (PBMCs) were stimulated by supernatant of HepG2.2.15 cells containing intact HBV virions, and the expression STING/TMEM173 gene was detected by real-time PCR. Results The results of immunohistochemical showed that STING/TMEM173 protein was higher in liver tissues of CHB patients and mainly expressed in inflammatory cells of liver tissue, and the expression of STING/TMEM173 protein was positively correlated with liver inflammation grade as well as serum ALT level. After transient and stable transfection by HBV whole genome plasmid, the STING/TMEM173 protein decreased significantly in HepG2 cells. In addition, HepG2.2.15 cell supernatant containing intact HBV virions promoted the expression of STING/TMEM173 in PBMC in a dose-dependent manner at RNA level. Conclusion HBV can up-regulate the expression of STING/TMEM173 protein in inflammatory cells of liver tissue, and the number of liver inflammatory cells expressing STING/TMEM173 may reflect the severity of liver inflammation.