Increased expression of miR-155 correlates with abnormal allograft status in solid organ transplant patients and rat kidney transplantation model

AIMS:Increasing evidence has shown the diagnostic value of miR-155 in organ transplantation. The dysregulation of miR-155 is reported to be associated with development of acute or chronic complications in solid organ transplant recipients. Here, we summarized related evidence to explore the correlation between the dysregulation of miR-155 and various allograft dysfunction in transplant recipients, and verified the dynamic change of miR-155 level in acute rejection (AR) using a rat renal transplantation model. MAIN METHODS:Eligible studies were retrieved from PubMed, Embase, and Cochrane Library databases. A meta-analysis method was performed to evaluate the diagnostic value of miR-155 in transplant recipients. Furthermore, the F344-Lewis rat renal transplantation model was established to validate the dynamic change of miR-155 expression during AR. KEY FINDINGS:A total of 275 transplant patients, including renal, heart, and lung transplantation from 6 studies were analysed. The pooled SEN of miR-155 was 0.87 (95% CI, 0.78-0.93), the pooled SPE was 0.76 (95% CI, 0.63-0.85), the pooled PLR was 3.6 (95% CI, 2.2-5.8), the pooled NLR was 0.17 (95% CI, 0.09-0.31), the pooled DOR was 17.31 (95% CI, 7.20-41.65) and pooled AUC was 0.89 (95% CI, 0.86-0.92). The rat renal transplantation model (n = 24) and control model (n = 15) were successfully established. Expression of miR-155 in plasma was significantly increased in 7 d and 9 d post-transplantation compared to the control group (P < 0.05), and was consistent with the dynamic change of AR degree. SIGNIFICANCE:miR-155 is a potential biomarker for monitoring the abnormal allograft status in solid organ transplantation.