Banff Human Organ Transplant Transcripts Correlate with Renal Allograft Pathology and Outcome: Importance of Capillaritis and Subpathologic Rejection

Microarray analysis of renal allograft biopsies has revealed important insights, including TCMR and AMR gene sets, but is limited to specially processed samples without pathology confirmation. We used the NanoString nCounter platform to perform mRNA analysis of archived formalin-fixed paraffin-embedded kidney allograft biopsies with the Banff Human Organ Transplant Panel. We correlated Banff pathology scores in the same tissue block with validated and custom gene sets and showed the importance of capillaritis. We identified subpathological transcripts that standard pathology would not have detected and transcripts, pathology, and clinical variables that predicted graft failure in TCMR and CAMR. These findings highlight the utility of archived samples in transplant pathology research and expand our understanding of the pathogenesis of rejection.