Novel antimicrobial peptide coating to prevent catheter-associated urinary tract infections

Introduction: Urinary catheters provide ideal surfaces for bacterial biofilm formation, being a major factor for hospital-acquired infections. With increased antibiotic resistance, there is a push for non-antibiotic-based measures to prevent catheter-associated urinary tract infections (CAUTI). I pursue the use of polymer-linked, broad-spectrum, host-defense-based antimicrobial peptides (AMPs) as novel catheter coatings. Here, I present the efficacy of tethered AMPs against common uropathogens both in vitro and in vivo. Materials and Methods: Peptides E6, Tet20, Tet26, and Kai13 were linked to surfaces using polymer brushes PDMA, PMPC, and PMPDSAH. All peptides were chosen based on their antimicrobial activity and biocompatibility as suggested by previously published papers. Antimicrobial activity of each coating was determined in vitro via colony counts 6 hours post-exposure to uropathogens. The in vivo efficacy of AMP coatings was also tested using a clinically relevant CAUTI mouse model; bladders of mice were catheterized percutaneously under ultrasound guidance, and 50 μL of 5E+5 CFU/mL P. aeruginosa was instilled. Indwelling polyurethane catheters and urine were collected after 7 days for examination of bacterial adherence and growth. Results: The most effective peptide-brush combination was E6-PDMA, decreasing bacterial adhesion and planktonic growth by up to 94.1% and 63.8%, respectively based on in vitro data. In vivo results look even more promising; the coating decreased bacterial adhesion by up to 99.9958% and planktonic growth by 99.8660% in comparison to untreated mice. Conclusions: Based on our in vitro and in vivo data, E6-PDMA coatings may effectively prevent CAUTI. Further testing of these novel coatings against more common uropathogens as well as tests to confirm the safety of such coatings will be important.Medicine, Faculty ofMedicine, Department ofExperimental Medicine, Division ofGraduat