Donor-Derived Cell-Free DNA to Diagnose Graft Rejection Post-Transplant: Past, Present and Future

Abstract

Donor-derived cell-free DNA (dd-cfDNA) is a non-invasive biomarker that is more sensitive and specific towards diagnosing any graft injury or rejection. Due to its applicability over all transplanted organs irrespective of age, sex, race, ethnicity, and the non-requirement of a donor sample, it emerges as a new gold standard for graft health and rejection monitoring. Published research articles describing the role and efficiency of dd-cfDNA were identified and scrutinized to acquire a brief understanding of the history, evolution, emergence, role, efficiency, and applicability of dd-cfDNA in the field of transplantation. The dd-cfDNA can be quantified using quantitative PCR, next-generation sequencing, and droplet digital PCR, and there is a commendatory outcome in terms of diagnosing graft injury and monitoring graft health. The increased levels of dd-cfDNA can diagnose the rejection prior to any other presently used biochemistry or immunological assay methods. Biopsies are performed when these tests show any signs of injury and/or rejection. Therefore, by the time these tests predict and show any unusual or improper activity of the graft, the graft is already damaged by almost 50%. This review elucidates the evolution, physiology, techniques, limitations, and prospects of dd-cfDNA as a biomarker for post-transplant graft damage and rejection.

Donor-Derived Cell-Free DNA as a Non-Invasive Biomarker for Graft Rejection in Kidney Transplant Recipients: A Prospective Study among the Indian Population

“…Consequently, both serum creatinine and biopsy serve as late markers, leading to delayed interventions, graft impairment, and potential rejection. This highlights the need for a novel biomarker that possesses attributes of accessibility, noninvasiveness, reproducibility, and heightened sensitivity and specificity [1,3,4,13]. The detection of donor or graft DNA in recipients' plasma holds promise as a biomarker for solid organ graft rejection due to remarkable sensitivity and specificity.…”

“…The current "gold standard" for evaluating graft status involves biopsy, a procedure fraught with inherent limitations such as invasive nature, prolonged turnaround times, interobserver variability, and high costs [1,4]. In renal transplant protocol biopsies, the incidence of hematuria and major complications has been documented at 3.5% and 1%, respectively [5].…”

“…Detecting minute quantities of dd-cfDNA or donor DNA in the recipient's plasma sample poses a challenge, yet it is attainable through advanced molecular biology methods. Various techniques exist for identifying and quantifying donor-derived cell-free DNA, including: (i) sequencing both donor and recipient genomes and pinpointing distinct single nucleotide polymorphisms (SNPs), (ii) recognizing the presence of the Y chromosome from a male graft in a female recipient, (iii) employing next-generation sequencing assays that use a panel of SNPs to discern donor DNA sans the requirement of a donor sample and sequencing, and (iv) employing a targeted approach where SNP assays are meticulously chosen based on minor allele frequency, and subsequently evaluated for applicability [1,4,13].…”

Advancements in Heart Transplantation: Donor-Derived Cell-Free DNA as Next-Generation Biomarker

“…The global accessibility of cfDNA testing exhibits significant disparities [37]. Wealthy nations are likely to adopt this advanced technology quickly.…”