Digital Spatial Mrna Profiling Reveals Distinct Endothelial Transcripts in Dsa+ and Dsa- Endarteritis in Kidney Allografts
1Department of Pathology, Massachusetts General Hospital, Boston, MA, 2NanoString Technologies, Inc., Seattle, WA, 3Department of Surgery, Massachusetts General Hospital, Boston, MA
Meeting: 2021 American Transplant Congress
Abstract number: 450
Keywords: Endothelial cells, Gene expression, Kidney transplantation, Rejection
Topic: Clinical Science » Kidney » Kidney Chronic Antibody Mediated Rejection
Session Information
Session Name: Kidney Alloimmune Responses
Session Type: Poster Video Chat
Date: Monday, June 7, 2021
Session Time: 7:30pm-8:30pm
Presentation Time: 7:30pm-7:40pm
Location: Virtual
*Purpose: Renal allograft biopsy transcript analysis is typically performed by microarray, which lacks spatial resolution. We initiated a systematic program using the NanoString GeoMx® Digital Spatial Profiler (DSP) to map mRNA expression in cells or regions of interest (ROIs) in formalin-fixed paraffin-embedded tissue (FFPE). Here we explore differences in endothelial transcripts in samples with endarteritis in DSA+ chronic antibody mediated rejection/CAMR and DSA- T cell mediated rejection/TCMR in nonhuman primate (NHP) kidney allografts.
*Methods: RNAse-free 5um FFPE sections of 2 DSA+ CAMR and 2 DSA- TCMR allograft nephrectomies with endarteritis from Cynomolgus NHPs (Smith 2018) were mounted on slides, hybridized with an 84-gene Immuno-Oncology probe set coupled to photocleavable oligonucleotide tags, and stained with fluorophore-labeled antibodies (DNA, pan-CK, CD45 and CD31). The slides were scanned to the GeoMx® DSP and discrete glomerular, arterial, and tubulointerstitial ROIs (n=48) were defined (Fig 1A-C) and segmented by CD31 expression. ROI tags were quantified on the nCounter® MAX analysis system and analyzed using GeoMx® DSP analysis software.
*Results: Differential expression analysis of TCMR arterial endothelial transcripts shows CXCL9 (p=0.003), CXCL10 (p=0.0004), and STAT1 (p=0.02) enrichment, while CAMR arterial endothelial transcripts show higher STAT2 (p=0.02), STAT3 (p=0.0006), and PECAM1 (p=0.003) expression, suggesting DSA-related differences in endothelial response (Fig 1D). Combined glomerular and peritubular capillary (PTC) endothelial transcripts in CAMR show higher ICAM1 (p=0.0006), IFNG (p=0.02), IL6 (p=0.03), and MKI67 (p=0.009). In CAMR, PTC endothelium shows higher HLADQ (p=0.001), HLADRB (p=0.001), CD74 (p=0.004) and BCL2 (p=0.02) than in glomeruli. The CD3/PECAM1 ratio (0.09) demonstrates CD31+ cell-derived transcript selectivity.
*Conclusions: Our data reveal endothelial transcript differences in endarteritis related to DSA and diversity of endothelial responses in kidney microvasculature. The GeoMx® DSP allows cell-specific transcript analysis in FFPE and is expected to reveal more insights in the pathogenesis of rejection.
To cite this abstract in AMA style:
Tomaszewski K, Medina MAraujo, Bruce A, Divakar P, Smith R, Kawai T, Colvin R, Rosales I. Digital Spatial Mrna Profiling Reveals Distinct Endothelial Transcripts in Dsa+ and Dsa- Endarteritis in Kidney Allografts [abstract]. Am J Transplant. 2021; 21 (suppl 3). https://atcmeetingabstracts.com/abstract/digital-spatial-mrna-profiling-reveals-distinct-endothelial-transcripts-in-dsa-and-dsa-endarteritis-in-kidney-allografts/. Accessed May 31, 2025.« Back to 2021 American Transplant Congress