BACKGROUND. Accurate detection of graft versus host disease (GVHD) is a major challenge in the management of patients that undergo hematopoietic stem cell transplantation (HCT). Here we demonstrate the use of circulating cell-free DNA (cfDNA) for detection of tissue turnover and chronic GVHD (cGVHD) in specific organs. METHODS. We established a cocktail of tissue-specific DNA methylation markers and used it to determine the concentration of cfDNA molecules derived from the liver, skin, lungs, colon and specific immune cells in 101 HCT patients. Results: Patients with an active cGVHD showed elevated concentration of cfDNA, as well as tissue-specific methylation markers that agreed with clinical scores. Strikingly, transplanted patients with no clinical symptoms had abnormally high levels of tissue-specific markers, suggesting hidden tissue turnover even in the absence of evident clinical pathology. An integrative model taking into account total cfDNA concentration, monocyte/macrophage cfDNA levels and Alanine transaminase (ALT) was able to correctly identify GVHD with a specificity of 86% and precision of 89% (AUC of 0.8). CONCLUSIONS. cfDNA markers can be used for the detection of cGVHD, opening a window into underlying tissue dynamics in patients that receive allogeneic stem cell transplants. FUNDING. This work was supported by grants from the Ernest and Bonnie Beutler Research Program of Excellence in Genomic Medicine, The Israel Science Foundation, the Waldholtz / Pakula family, the Robert M. and Marilyn Sternberg Family Charitable Foundation and the Helmsley Charitable Trust (to Y.D).
Batia Avni, Daniel Neiman, Elior D. Shaked, Ofer Gal-Rosenberg, Sigal Grisariu, Mona Kuzli, Ilai Avni, Andrea Fracchia, Polina Stepensky, Tsila Zuckerman, Ahinoam Lev-Sagie, Ilana Fox-Fisher, Sheina Piyanzin, Joshua Moss, Seth J. Salpeter, Benjamin Glaser, Ruth Shemer, Yuval Dor