Ko Raymond, Cadieux Peter A, Dalsin Jeffrey L, Lee Bruce P, Elwood Chelsea N, Razvi Hassan
Department of Surgery, Division of Urology, Schulich School of Medicine and Dentistry, The University of Western Ontario, London, Ontario, Canada.
J Endourol. 2008 Jun;22(6):1153-60. doi: 10.1089/end.2008.0049.
Success in the prevention of urinary device infections has been elusive, largely due to multiple bacterial attachment strategies and the development of urinary conditioning films. We investigated a novel anti-fouling coating consisting of mussel adhesive protein mimics conjugated to polyethylene glycol (mPEG-DOPA(3)) for its potential to resist conditioning film formation and uropathogen attachment in human urine.
Model TiO(2) -coated silicon disks ( approximately 75 mm(2)) were either coated with mPEG-DOPA(3) or left uncoated and sterilized using ethylene oxide gas. For bacterial attachment experiments, coated and uncoated surfaces were separately challenged with bacterial strains comprising six major uropathogenic species for 24 hours at 37 degrees C in human pooled urine. Starting inoculum for each strain was 10(5) CFU/mL and 0.5 mL was used per disk. Following incubation, the disks were thoroughly rinsed in phosphate buffered saline to remove non-adherent and weakly-adherent organisms and cell scrapers were employed to dislodge those that were firmly attached. Adherent bacteria were quantitated using dilution plating. Representative disks were also examined using scanning electron microscopy, energy dispersive x-ray analysis, and live/dead viability staining.
The mPEG-DOPA(3) coating significantly resisted the attachment of all uropathogens tested, with a maximum >231-fold reduction in adherence for Escherichia coli GR-12, Enterococcus faecalis 23241, and Proteus mirabilis 296 compared to uncoated TiO(2) disks. Scanning electron microscopy and viability staining analyses also reflected these results and demonstrated the ability of the coating to resist urinary constituent adherence as well.
Model surfaces coated with mPEG-DOPA(3) strongly resisted both urinary film formation and bacterial attachment in vitro. Future in vitro and in vivo studies will be conducted to assess whether similar findings can be demonstrated when these polymer coatings are applied to urologic devices.
预防泌尿系统器械感染一直难以取得成功，这主要归因于多种细菌附着策略以及尿调节膜的形成。我们研究了一种新型防污涂层，该涂层由与聚乙二醇共轭的贻贝粘附蛋白模拟物（mPEG-DOPA(3)）组成，以探究其在人尿液中抵抗调节膜形成和尿路病原体附着的潜力。
将模型TiO(2)涂层硅盘（约75平方毫米）用mPEG-DOPA(3)涂层或不涂层，并用环氧乙烷气体进行灭菌。在细菌附着实验中，将涂层和未涂层的表面分别用包含六种主要尿路致病菌种的菌株在人混合尿液中于37℃下挑战24小时。每种菌株的起始接种量为10(5) CFU/mL，每个圆盘使用0.5 mL。孵育后，将圆盘在磷酸盐缓冲盐水中彻底冲洗以去除未附着和弱附着的生物体，并用细胞刮刀去除牢固附着的生物体。使用稀释平板法对附着细菌进行定量。还使用扫描电子显微镜、能量色散X射线分析和活/死活力染色对代表性圆盘进行检查。
mPEG-DOPA(3)涂层显著抵抗了所有测试尿路病原体的附着，与未涂层的TiO(2)圆盘相比，大肠杆菌GR-12、粪肠球菌23241和奇异变形杆菌296的附着减少最多>231倍。扫描电子显微镜和活力染色分析也反映了这些结果，并证明了该涂层抵抗尿液成分附着的能力。
涂有mPEG-DOPA(3)的模型表面在体外强烈抵抗尿膜形成和细菌附着。未来将进行体外和体内研究，以评估当这些聚合物涂层应用于泌尿外科器械时是否能得到类似的结果。
