Abstract 17459: Donor Organ Specific Exosome Platform for Monitoring Transplant Organ Rejection in an in vivo Mouse Heterotopic Heart Transplant Model

Introduction: In heart transplantation, there is a critical need for development of serum biomarkers to monitor for donor organ rejection/ injury, which remains a major cause of morbidity and mortality. Exosomes are tissue and major histocompatibility complex (MHC) specific microvesicles (30-200 nm) with stable RNA cargo reflecting conditional state of the tissue releasing them. Their application in biomarker discovery is implicated in several fields. Hypothesis: We hypothesize that transplant organ releases donor tissue-specific exosomes into the recipient blood that can be serially monitored. Characterization of donor organ specific exosome profiles and their RNA cargo can serve as potential novel biomarkers for monitoring transplant organ rejection/ injury. Methods: In mouse acute rejection model of full MHC mismatch heterotopic heart transplantation (BALB/c into B6, n=10), plasma exosome pool was isolated from recipient blood using Sepharose gel filtration chromatography, and was assessed at different...