Associate Professor UT Southwestern Medical Center
Introduction: Urinary voiding dysfunction is highly prevalent in aging women. A deeper understanding of the cellular composition of female urethra in the non-diseased state could provide insights into the etiology of dysfunction. Single cell RNA sequencing was performed on female urethra to generate a cellular atlas. Methods: Urethra from female organ donors aged 18-45 (N=4) was collected fresh from surgery and enzymatically digested into a single cell suspension. Single cell RNA sequencing was performed using 10x Genomics V3 chemistry. Data were analyzed in Seurat for cell type annotation. Immunohistochemical validation of cell types was performed on FFPE sections using differentially expressed genes from clustered data. Results: The female proximal urethral lumen is lined with a stratified urothelium composed of KRT5+/KRT14- basal cells with KRT13+ hillock epithelia and KRT4+ luminal epithelia. Ducts emerging from dorsal urethra (Skene's glands) contain basal and club cells similar to prostatic urethra. The urethral lumen is surrounded by two discrete layers of fibroblasts (peri-urethral and interstitial) and circumferential smooth muscle and skeletal muscle. Conclusions: The identification of 1) specialized fibroblasts surrounding the urethra, and 2) club cells in dorsal ducts could yield new insight into the regulation of infection, inflammation and obstruction, which are the putative etiologies of most urethral dysfunction. SOURCE OF Funding: DK115477, DK104310, DK129994