Translational characterization of hepatic miR-301a as a biomarker for acute rejection in experimental and clinical liver transplantation

Using a rat orthotopic liver transplantation (OLT) model and microarray, we compared the expression profiles of microRNAs in naïve and AR livers at day 7 after OLT obtained from the rats with short-term (<14 days, DA-LEW) or long-term (>60 days, DA-PVG) survival fate. AR-related microRNAs and pro-inflammatory cytokines were validated by using a quantitative real-time PCR. AR-related microRNA-mediated inflammatory responses were evaluated by overexpression of a target microRNA in rat primary hepatocytes. Human liver biopsies from recipients with AR or abnormal liver function were used for clinical verification. The microarray revealed that miR-301a was significantly upregulated in lethal AR livers of DA-LEW, while it was comparable to the naïve livers in DA-PVG, which spontaneously overcomes AR.本研究采用大鼠原位肝移植（orthotopic liver transplantation, OLT）模型结合微阵列芯片（microarray）技术，对比了取自短期存活（<14天，DA-LEW品系）或长期存活（>60天，DA-PVG品系）大鼠的原位肝移植术后第7天的未发生急性排斥反应（Acute Rejection, AR）与急性排斥反应肝脏中微小RNA（microRNAs）的表达谱。随后，采用实时荧光定量聚合酶链反应（quantitative real-time PCR）对急性排斥反应相关微小RNA及促炎细胞因子进行验证。通过在大鼠原代肝细胞中过表达目标微小RNA，评估急性排斥反应相关微小RNA介导的炎症应答。本研究还纳入来自急性排斥反应受体或肝功能异常受体的人类肝活检样本，用于临床验证。微阵列芯片分析结果显示，miR-301a在DA-LEW品系大鼠的致死性急性排斥反应肝脏中显著上调；而在可自发缓解急性排斥反应的DA-PVG品系大鼠中，miR-301a的表达水平与未发生急性排斥反应的肝脏相当。