title: A fast and simple method for detecting and quantifying donor-derived cell-free DNA in sera of solid organ transplant recipients as a biomarker for graft function.
abstract: BACKGROUND
  Timely detection of graft rejection is an important issue in the follow-up care after solid organ transplantation. Until now, biopsy has been considered the "gold standard" in the diagnosis of graft rejection. However, non-invasive tests such as monitoring the levels of cell-free DNA (cfDNA) as a sensitive biomarker for graft integrity have attracted increasing interest. The rationale of this approach is that a rejected organ will lead to a significant release of donor-derived cfDNA, which can be detected in the serum of the transplant recipient.
  
  
  METHODS
  We have developed a novel quantitative real-time PCR (qPCR) approach for detecting an increase of donor-derived cfDNA in the recipient's serum. Common insertion/deletion (InDel) genetic polymorphisms, which differ between donor and recipient, are targeted in our qPCR assay. In contrast to some other strategies, no specific donor/recipient constellations such as certain gender combinations or human leukocyte antigen (HLA) discrepancies are required for the application of our test.
  
  
  RESULTS
  The method was first validated with serial dilutions of serum mixtures obtained from healthy blood donors and then used to determine donor-derived cfDNA levels in patients' sera within the first 3 days after their kidney transplantation had been performed.
  
  
  CONCLUSIONS
  Our method represents a universally applicable, simple and cost-effective tool which can potentially be used to detect graft dysfunction in transplant recipients.
authors.forename: Martina
authors.initials: M
authors.lastname: Adamek
authors.forename: Gerhard
authors.initials: G
authors.lastname: Opelz
authors.forename: Katrin
authors.initials: K
authors.lastname: Klein
authors.forename: Christian
authors.initials: C
authors.lastname: Morath
authors.forename: Thuong Hien
authors.initials: TH
authors.lastname: Tran
mesh_terms: D015415:Biomarkers / Q000097:blood*; D001782:Blood Donors; D016022:Case-Control Studies; D004247:DNA / Q000097:blood* / Q000235:genetics; D006084:Graft Rejection / Q000097:blood / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D007674:Kidney Diseases / Q000601:surgery; D016030:Kidney Transplantation / Q000009:adverse effects*; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D066027:Transplant Recipients
chemical_list: D015415:Biomarkers; D004247:DNA