Identifying host factors required for the long-term intracellular survival of uropathogenic Escherichia coli

Urinary-tract infections (UTIs) are among the most common infections, and their management is becoming increasingly challenging due to infection recurrence and the rise of multidrug-resistant bacteria. Uropathogenic Escherichia coli (UPEC) is responsible for approximately 80% of UTIs and can persist intracellularly within bladder urothelial cells for weeks. However, the host factors that permit intracellular persistence remain poorly defined. Within hours post-invasion, UPEC forms intracellular bacterial colonies, and a subset of these intracellular bacteria transition into quiescent intracellular reservoirs, which are thought to play a critical role in persistence and recurrence.Here, I aim to identify host factors required for the long-term intracellular survival of UPEC. I will use a tractable 2D human urothelial model to assess the survival of multiple UPEC strains, including clinical isolates. Using high-resolution confocal microscopy, I will map UPEC’s intracellular niche from early through late stages of infection. Guided by these data, I will conduct a targeted, pooled CRISPR-knockout screen to determine host genes required for long-term UPEC intracellular survival. Together, this work will identify novel host factors critical for long-term UPEC intracellular survival, thereby providing potential targets for much- needed novel therapeutics for recurrent and difficult-to-treat UTIs.Keywords: Urinary tract infections; Uropathogenic E. coli; survival