MicroRNA expression in the acute rejection of liver transplantation in rats

Abstract

Objective To investigate the role of miRNA expression in the acute rejection of liver transplantation in rats.Methods The rat orthotopic liver transplantation (ROLT) was performed using the two-cuff technique described by Kamada with modification.Rats were randomly divided into two groups,a rejection group (n=12) and a control group (n=12).MicroRNA microarray technology was used to screen the microRNA expression profile in peripheral blood on the 7th postoperative day,and the bioinformatics microRNA screening method detected that miR-206 had the biggest difference in expression level.Peripheral blood samples were gathered before,3 days,5 days,and 7 days after ROLT to analyze the expression level of miR 206 quantitatively with qRT PCR technology.Dynamic contrast analysis was made between the quantitative results of miR-206 and the results of pathological examination and liver function tests.Results There was no significant difference in miR-206 expression level between the rejection group and control group before the operation (t=0.105,P=0.921).MiR-206 expression was significantly higher in the rejection group than in the control group 3 days after ROLT (t=8.875,P=0.001).The expression level of miR 206 in the rejection group also increased gradually over time (F=32.154,P＜0.01).However,pathological changes and liver function index did not show obvious differences until the 5th and 7th day postoperatively.The expression of miR-206 in peripheral blood and graft was strongly and positively correlated with the rejection active index (RAI) of acute liver rejection pathology (0.812 and 0.881 respectively,P＜0.01).In the rejection group,the miR-206 level in peripheral blood and graft were positively associated with each other.Conclusions Detection of miR-206 in peripheral blood was significantly better than pathological examination and liver function test in the diagnosis of acute rejection of rat liver transplantation.Moreover,miR-206 was an early sensitive and specific marker for making this diagnosis. Key words: MicroRNA; Liver transplantation; Rat; Acute rejection