Test for Early Rejection of Transplanted Organs

For years, medical researchers have sought an early test to determine how well a transplant patient’s body is accepting an organ. Half of kidney recipients have organ failure within 10 years of a transplant.

Now, two companies have produced a test that may help to solve the problem of detecting early rejection.

Graft-derived, cell-free DNA (Gcf- DNA) in the blood of transplant recipients is considered a potential biomarker for organ rejection. Previous attempts to determine GcfDNA levels, which required sequencing of both donor and recipient DNA, have been expensive, required a long turnaround, and also meant donor DNA specimens were necessary.

Chronix Biomedical researchers, along with research partner University Medical Center Göttingen, wanted to develop a new method that would address these drawbacks. As described by the team of scientists, the new method uses Bio-Rad Laboratories’ Droplet Digital PCR (ddPCR) technology to overcome obstacles of earlier tests, which were both time-consuming and costly.

The new method reduces test time from 3 days or more to 1 day and cuts costs by 90 percent, the authors said. They were able to address the past need for donor DNA by preselecting single nucleotide polymorphisms (SNPs, small, comparable differences in sections of DNA) that ensure enough difference between donor and recipient DNA as to be detectable.

The method was presented at the American Association of Clinical Chemistry 2013 annual meeting.