Biophysical Society Thematic Meeting | Ascona 2026

Mechanobiology of Infection

Poster Abstracts

2-POS Board 2 DEVELOPMENT OF A BIOMECHANICALLY ACTIVE MODEL OF CATHETER

ASSOCIATED URINARY TRACT INFECTION Théo ASPERT ; Gauri Paduthol 1 ; John McKinney EPFL, SV GHI, Lausanne, Switzerland

Background: Urinary catheters are among the most common indwelling medical devices globally. Their presence dramatically increases the risk of bacterial colonization, promoting pathogen adhesion and biofilm formation by altering urination dynamics and introducing an exogenous surface. This frequently results in Catheter-Associated Urinary Tract Infections (CAUTIs), a leading cause of nosocomial infections. Despite extensive research, current methods for investigating CAUTI mechanisms remain limited.Goal: We aim to develop a biomechanically active microphysiological model of CAUTI that accurately reproduces key aspects of the catheterized urinary tract microenvironment and the influence of stretching on infection dynamics. Approach: We fabricated a PDMS-based microfluidic device featuring a hydrogel chamber, molded into a cylinder lumen, and seeded with bladder epithelial cells. This yields a stratified, differentiated, and perfusable bladder epithelium (an "urothelium-on-chip"). The model is biomechanically active, supporting time-lapse microscopy at a resolution of 0.2 µm and allowing for urine flow and tissue stretching via hydrostatic pressure, mimicking in vivo bladder dynamics. Crucially, the system can be directly catheterized using a microtube, accurately reproducing the tissue-surface-flow interaction. Immediate next steps involve characterizing the tissue response to the catheter and infecting the system with uropathogens to understand specific mechanisms of adhesion, biofilm formation, tissue invasion, and antibiotic persistence relevant to CAUTIs, specifically focusing on how physiological stretching modulates these processes. Platform Design and Future Outlook: The fabrication protocol was intentionally designed to be simply reproducible to facilitate widespread adoption. The platform's modular nature allows for future complexity upgrades, such as integrating immune cells and vasculature within the hydrogel, providing a pathway to model the systemic host response to microbial interactions.

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