Circulating cell‐free DNA in liver transplantation: A pre‐ and post‐transplant biomarker of graft dysfunction.

Background Methods Results Conclusions Liver transplantation (LT) is still limited by organ shortage and post‐transplant monitoring issues. While machine perfusion techniques allow for improving organ preservation, biomarkers like donor‐derived cell‐free DNA (dd‐cfDNA) and mitochondrial cfDNA (mt‐cfDNA) may provide insights into graft injury and viability pre‐ and post‐LT.A prospective observational cohort study was conducted on LT recipients (n = 45) to evaluate dd‐cfDNA as a biomarker of graft dysfunction during the first 6 months after LT. Dd‐cfDNA was quantified on blood samples collected pre‐LT and post‐LT using droplet digital PCR. In livers undergoing dual hypothermic oxygenated machine perfusion (D‐HOPE), total cfDNA and mt‐cfDNA levels were measured on perfusate samples collected at 30‐min intervals. Correlations with graft function and clinical outcomes were assessed.Dd‐cfDNA levels peaked post‐LT and correlated with transaminase levels and histological injury severity. The longitudinal assessment showed that postoperative complications and rejection were associated with an increase in dd‐cfDNA levels. Mt‐cfDNA levels in D‐HOPE perfusate correlated with graft function parameters post‐LT and were higher in patients with early allograft dysfunction and severe complications.This study confirms dd‐cfDNA as a marker of graft injury after LT and suggests that perfusate mt‐cfDNA levels during D‐HOPE correlate with graft function and post‐transplant clinical outcome. Integration of these tests into clinical practice may improve transplant management and viability assessment during hypothermic perfusion. [ABSTRACT FROM AUTHOR]