Graft-derived cell-free DNA as a biomarker in liver transplantation

Improvement of long-term patient and graft outcome is still a challenge in liver transplantation. Personalized approaches to immunosuppressive treatment of liver transplant patients are currently under investigation, as conventional markers have limited usefulness to predict drug efficacy. The presence of graft-derived cell-free DNA (GcfDNA) in the plasma of liver transplant recipients opens up the possibility of monitoring allograft injury through measurement of this molecular marker. A rapid, cost-effective droplet digital PCR (ddPCR) method has been developed for the quantification of donor DNA. GcfDNA has shown to be useful for the detection of subclinical and full-blown acute rejection and non-rejection-related liver injury (e.g., HCV infection, liver trauma, ischemia/reperfusion damage). GcfDNA allows for the early detection of transplant injury (“liquid biopsy”) and enables earlier more effective treatment intervention. It is especially helpful to guide changes in immunosuppression and to monitor immunosuppression minimization. This new approach may contribute to achieve more effective, less toxic personalized immunosuppression.