New Delhi, Aug 7 : Donor-derived cell-free DNA (dd-cfDNA), also known as liquid biopsy, has the potential for early detection of kidney transplant rejection, a new study shows.

The international study enrolled kidney transplant recipients - both adult and paediatric - from 14 transplantation centres in Europe and the US.

In inflammation associated with transplant rejection, dying cells release donor-derived cell-free DNA (dd-cfDNA) into the bloodstream.

Researchers found that dd-cfDNA levels were strongly correlated with different types of transplant rejection, including antibody-mediated rejection, T cell-mediated rejection, and mixed rejection. The study found similar accuracy in both children and adults.

Currently, unnecessary and invasive graft biopsies are considered the "gold standard" for diagnosing transplant rejection. However, dd-cfDNA could provide a non-invasive, accurate biomarker to reduce the need for biopsy.

Two Indian origin Washington University School of Medicine researchers Raja Dandamudi, MD, and Vikas Dharnidharka, MD, MPH, contributed to the study, led by researchers from the Universite Paris Cite and doctors from the Assistance Publique - Hopitaux de Paris.

"Many studies of newer biomarkers to detect acute rejection in kidney transplants are not very large and cannot study various sub-populations, limiting their generalizability," Dharnidharka said. This work was a very large international collaboration. The analyses demonstrated that dd-cfDNA improves the acute rejection detection beyond our standard of care monitoring, including in subpopulations of transplant recipients who are of African ancestry or of pediatric age."

"This paper advances our understanding of the benefits of using cf-DNA as a biomarker for rejection and outcomes in the field of kidney transplantation." said Tarek Alhamad, professor of Medicine at WashU Medicine.

While biopsies will continue as the method of rejection diagnosis, dd-cfDNA may improve early rejection diagnosis and enhance the care of kidney transplant recipients.

/IANS