Single-cell transcriptional profiling of advanced renal fibrosis identifies novel specific fibroblast marker and disease target

Dissecting the molecular and cellular nature of advanced renal fibrosis is principal for mechanistic understanding of chronic kidney disease (CKD) and developing targeted strategies against its progression. Aberrant renal fibroblast activation and unresolved tubular epithelial injury are key contributors to excessive extracellular matrix (ECM) production and kidney function loss. However, the transcriptional and cellular identities of activated renal fibroblasts remain poorly characterized. Moreover, historically used markers compromise specificity of activated renal fibroblasts tracing and targeting. Here, we created comprehensive single cell transcriptional profiles of two clinically relevant long-term renal fibrosis models and revealed three distinctive “secretory”, “contractile” and “migratory” fibroblast clusters. We identified a novel specific renal activated fibroblast marker expressed in all three populations. Advanced kidney fibrotic remodeling elicited sustaining developmental signature and pronounced epithelial-to-stromal crosstalk. Furthermore, we mechanistically validated AHNAK as a putative novel target of kidney injury in a primary human in vitro model of epithelial-to-mesenchymal transition. UIR and UUO injured kidneys were compared to controls vis single-cell RNAseq. The Ctrl, N, and AN samples are all controls. The controls were done in three different batches.