WT1+ parietal epithelial progenitor cells are essential for renal proximal tubule repair and regeneration

Purpose: We have found that WT1+ parietal epithelial progenitor cells contribute to renal proximal tubule repair and regeneration by cell lineage tracing and direct differentiation analysis, but the transcription profile of these WT1+ PECs is largely unkown. Here, we aimed to unveil the transcriptional features of WT1+ PECs through single-cell RNA sequencing (scRNA-seq). Methods: Single cell suspension was prepared from kidney cortex of WT1CreERT2; Rosa26-tdTfl/+ mice that underwent sham or ischemic reperfusion injury (IRI) 24h .TdT+ cells were enriched by fluorescence activated cell sorter (FACS) and further analyzed with BD Rhapsody platform. Results: After quality control and cell filtering, 26,759 cells were informative (Dataset S1) and divided into 10 clusters using Harmony algorithm to reduce batch effects. GO analysis and QuSAGE heatmap suggested that WT1+ PECs might promote kidney regeneration after AKI through TGF-ß and Notch signaling pathway. Marker gene expression analysis showed that WT1+ PECs shared the characteristics of STCs. Pseudotemporal analysis indicated that that WT1+ PECs developed to PTECs through STCs intermediate stage. Conclusions: scRNA-seq indicated that the rare, quiescent PECs supplied PTECs through STCs intermediate stage after severe ischemic injury, and this process most likely was regulated through TGF-ß and Notch signaling pathway. Overall design: Single cell mRNA sequence of kidneys from sham or IRI 24h WT1CreERT2; Rosa26-tdTfl/+ mice and focus on the gene expression profile of WT1+ PECs.