Abstract: FR-OR45
Single-Cell RNA-Sequencing Analysis of Kidney Transplant Biopsies Demonstrates a Proinflammatory Role for Renal Tubular Cells in Rejection
Session Information
- In-Depth Look at Transplantation: Basic and Translational
October 23, 2020 | Location: Simulive
Abstract Time: 05:00 PM - 07:00 PM
Category: Transplantation
- 1901 Transplantation: Basic
Authors
- Malone, Andrew F., Washington University in Saint Louis, Saint Louis, Missouri, United States
- Leckie-Harre, Aidan, Washington University in Saint Louis, Saint Louis, Missouri, United States
- Wu, Haojia, Washington University in Saint Louis, Saint Louis, Missouri, United States
- Humphreys, Benjamin D., Washington University in Saint Louis, Saint Louis, Missouri, United States
Background
Antibody mediated rejection (AMR) remains one of the major causes of allograft failure and our understanding of this disease process is poor. CXCL12 is thought to contribute to allograft rejection through T cell recruitment and a CXCL12 promotor variant is associated with worse graft outcomes. We performed single cell RNAseq on biopsies from transplant patients to examine ligand expression in kidney cells.
Methods
The 10X Genomics platform was used to make libraries which were sequenced to a depth of ~50k reads/cell. Gene-cell matrices were obtained from CellRanger and the downstream analysis (clustering, integration analysis, expression analyses) were done using R and Seurat. This study had IRB approval.
Results
81139 cells in total (avg = 1124 genes/cell) from 5 kidney transplant biopsy samples (2 non-rejecting, 3 ABMR) were included in the final integrated analysis using UMAP. All major kidney cell types were identified as well as macrophages, B cells and T cells. Renal epithelial cells from rejection samples differentially expressed ligands with cognate receptors found on immune cells. All renal tubular cell types increase HLA gene expression allowing allowing for ligation of macrophage and T cell cognate receptors LILRB and CD3, respectively. Interestingly, only loop of Henle cells increased expression of CXCL12 whereas stromal cells decreased CXCL12 expression in rejection samples.
Conclusion
Comprehensive single cell RNAseq of human kidney transplant biopsies suggests a role for loop of Henle cells in rejection though expression of CXCL12. We also demonstrate that stromal cells, known to express CXCL12, downregulate CXCL12 expression in rejection. These data suggest a pro-inflammatory role for tubular cells in rejection.
Funding
- NIDDK Support