An ectopically expressed serum miRNA signature is prognostic, diagnostic, and biologically related to liver allograft rejection

Abstract

The ability to noninvasively diagnose acute cellular rejection (ACR) with high specificity and sensitivity would significantly advance personalized liver transplant recipient care and management of immunosuppression. We performed microRNA (miRNA) profiling in 318 serum samples from 69 liver transplant recipients enrolled in the Immune Tolerance Network immunosuppression withdrawal (ITN030ST) and Clinical Trials in Organ Transplantation (CTOT-03) studies. We quantified serum miRNA at clinically indicated and/or protocol biopsy events (n 5 130). The trajectory of ACR diagnostic miRNAs during immunosuppression withdrawal were also evaluated in sera taken at predetermined intervals during immunosuppression minimization before and at clinically indicated liver biopsy (n 5 119). Levels of 31 miRNAs were significantly associated with ACR diagnosis with two miRNAs differentiating ACR from non-ACR (area under the receiver operating characteristic curve 5 90%, 95% confidence interval 5 82%-96%) and predicted ACR events up to 40 days before biopsy-proven rejection. The most differentially expressed miRNAs were low or absent in the blood of healthy individuals but highly expressed in liver tissue, indicating an ectopic origin from the liver allograft. Pathway analyses of rejection-associated miRNAs and their target messenger RNAs (mRNAs) showed induction of proinflammatory and cell death-related pathways. Integration of differentially expressed serum miRNA with concordant liver biopsy mRNA demonstrates interaction between molecules with a known role in transplant rejection. Conclusion: Distinct miRNA levels profiled from sera at the time of clinical allograft dysfunction can be used to noninvasively diagnose ACR. Predictive trajectories of the same profile during supervised immunosuppression minimization diagnosed rejection up to 40 days prior to clinical expression. The rejection-associated miRNAs in sera appear to be ectopically expressed liver and specific immune cell miRNAs that are biologically related, and the consequences of immune-mediated damage to the allograft. (HEPATOLOGY 2017;65:269-280). SEE EDITORIAL ON PAGE 15L iver transplantation is currently the only treatment option for end-stage liver failure, with patient survival rates of approximately 88% observed in the first year after transplantation.(1) Standard immunosuppression entails calcineurin inhibitorbased therapies, and for most patients is aimed at achieving and maintaining therapeutic trough levels. Recipients who have clinical evidence of allograft dysfunction, usually indicated by elevated bilirubin and/or

MicroRNA‑370 suppresses the progression and proliferation of human astrocytoma and glioblastoma by negatively regulating β‑catenin and causing activation of FOXO3a

“…miRNAs are involved in the regulation of gene expression through RNA silencing and post-transcriptional gene silencing via binding to the 3'-untranslated region (3'-UTR) of specific mRNAs (11,12). miRNAs regulate diverse aspects of development and physiology, such as metabolic diseases (13), cardiovascular disease (14,15), immune dysfunction (16,17) and cancer (18,19). A large number of studies have reported that miRNAs are key factors in regulating cell differentiation and growth, migration, apoptosis and necrosis.…”

The release of microRNA‐122 during liver preservation is associated with early allograft dysfunction and graft survival after transplantation

“…In the search for viable biomarkers, microRNAs (miRNAs) have gained interest due to their low complexity, stability, and organ specificity. Many studies have shown that miRNAs released in biofluids like serum, urine, and bile can be used as sensitive and accurate biomarkers . They are associated with a variety of pathologic conditions and control many cellular processes including tissue injury and repair .…”

Cell‐free microRNAs as early predictors of graft viability during ex vivo normothermic machine perfusion of human donor livers

“…miRs can withstand harsh environmental conditions, and because the perfusate circulates through the entire liver during machine perfusion, miR levels in perfusate provide a better and non‐invasive representation of the entire liver compared to miR levels measured in total RNA samples from biopsies . Furthermore, miRs have been shown to be earlier and more sensitive markers of liver damage than more conventional markers such as AST or ALT, and machine perfusion potentially allows for an even more representative and dynamic evaluation of the liver graft . In addition, machine perfusion can be used for the resuscitation of grafts but fast and predictive biomarkers, such as miRs, are necessary to assess the effects of the treatment provided .…”

“…11 Furthermore, miRs have been shown to be earlier and more sensitive markers of liver damage than more conventional markers such as AST or ALT, and machine perfusion potentially allows for an even more representative and dynamic evaluation of the liver graft. 16,25,26 In addition, machine perfusion can be used for the resuscitation of grafts but fast and predictive biomarkers, such as miRs, are necessary to assess the effects of the treatment provided. [27][28][29][30] Especially HDmiR-122, which is involved in several processes in the liver such as lipid metabolism, has the po- Studies have shown that HDmiR-122 levels in graft preservation fluid are higher in DCD grafts and in livers that went on to develop EAD and NAS.…”