A Multicenter Experience in the Use of Allomap and Allosure Surveillance Strategies in Multiorgan Heart-Kidney and Heart-Liver Transplantation

PurposeNon-invasive surveillance for monitoring allograft health using combination gene-expression profile testing (AlloMap) and donor-derived cell-free DNA (ddcfDNA) (AlloSure) has gained significant momentum. Data supporting the utilization of these assays has been established in single organ heart transplantation (HT), however is yet to not been validated in multiorgan transplantation. Herein we report the largest multicenter experience on the use of AlloMap (AM) and AlloSure (AS) assays as a non-invasive surveillance strategy in Heart-Kidney (HKT) and Heart-Liver (HLT) transplant recipients.MethodsMulticenter, prospectively collected datasets from USC Medical Center and UCLA Medical Center were queried for patients who underwent either HKT or HLT with an AM and AS allograft surveillance strategy. This was compared to data for patients who underwent HT alone, derived from the Donor Derived Cell-Free DNA Outcomes AlloMap Registry (D-OAR) - a prospective, observation study of HT recipients monitored with AM and AS. Patients with CMV and rejection (≥2R) were excluded.ResultsThere were 300 HT recipients, 28 HKT recipients and 13 HLT recipients. The median AM and AS scores for HT recipients (N=300) were 29.0 and 0.09%, respectively. In comparison, the median AlloMap and AlloSure scores for HKT (N=28) recipients were 32.7 and 0.18%, respectively. Similarly, for HLT (N=13) recipients the median AM and AS scores were 34.0 and 3.54%, respectively.ConclusionWhile AS scores were slightly higher in the HKT cohort compared to HT alone, they were substantially higher for HLT recipients. We note a similar trend of higher AM scores across HKT and HLT recipients compared to HT alone. These patterns are observational and hypothesis generating demanding further investigation to more accurately interpret gene-expression and ddcfDNA profiles at baseline and in the setting of acute allograft rejection in multiorgan transplantation recipients. Non-invasive surveillance for monitoring allograft health using combination gene-expression profile testing (AlloMap) and donor-derived cell-free DNA (ddcfDNA) (AlloSure) has gained significant momentum. Data supporting the utilization of these assays has been established in single organ heart transplantation (HT), however is yet to not been validated in multiorgan transplantation. Herein we report the largest multicenter experience on the use of AlloMap (AM) and AlloSure (AS) assays as a non-invasive surveillance strategy in Heart-Kidney (HKT) and Heart-Liver (HLT) transplant recipients. Multicenter, prospectively collected datasets from USC Medical Center and UCLA Medical Center were queried for patients who underwent either HKT or HLT with an AM and AS allograft surveillance strategy. This was compared to data for patients who underwent HT alone, derived from the Donor Derived Cell-Free DNA Outcomes AlloMap Registry (D-OAR) - a prospective, observation study of HT recipients monitored with AM and AS. Patients with CMV and rejection (≥2R) were excluded. There were 300 HT recipients, 28 HKT recipients and 13 HLT recipients. The median AM and AS scores for HT recipients (N=300) were 29.0 and 0.09%, respectively. In comparison, the median AlloMap and AlloSure scores for HKT (N=28) recipients were 32.7 and 0.18%, respectively. Similarly, for HLT (N=13) recipients the median AM and AS scores were 34.0 and 3.54%, respectively. While AS scores were slightly higher in the HKT cohort compared to HT alone, they were substantially higher for HLT recipients. We note a similar trend of higher AM scores across HKT and HLT recipients compared to HT alone. These patterns are observational and hypothesis generating demanding further investigation to more accurately interpret gene-expression and ddcfDNA profiles at baseline and in the setting of acute allograft rejection in multiorgan transplantation recipients.