(1002) Differences in Individual Blood Gene Expression Profile (GEP) Levels in T-Cell Mediated Rejection Assessed by Molecular Microscopy in Heart Transplant

PurposeBlood gene expression profile (GEP) is being used for non-invasive surveillance of T cell-mediated rejection (TCMR) in orthotopic heart transplant (OHT). While blood GEP presented as an ordinal score to clinicians, it a summary quantification 11 different mRNA levels relevant TCMR. Whether the circulating individual genes are pathways that occur tissue (Molecular Microscopy Diagnostic System; MMDx) unknown. The aim this study was explore relationship between and OHT patients with TCMR diagnosed by molecular pathology or endomyocardial biopsy.MethodsWe retrospectively reviewed all from August 2021 May 2022 underwent both biopsy MMDx (One Lambda) within 2-week period. We retrieved CareDx Inc. Student t-test performed compare found without assessed EMB.ResultsA total 173 paired samples 125 were included analysis. There 15 (8.7%) MMDx. 5 (2.9%) EMB (Table 2). only MARCH8, which highly expressed myeloid cells involved inflammation 1). several differentially EMB, but not modalities.ConclusionBlood MARCH8 EMB. Further studies should investigate relation myocardial GEP, may elucidate novel common pathway. Blood biopsy. A modalities.