Institute of Pharmaceutical Science, Faculty of Life Science & Medicine, King's College London, London, UK.
School of Biomedical Engineering & Imaging Sciences, Faculty of Life Science & Medicine, King's College London, London, UK.
Diagn Microbiol Infect Dis. 2024 Dec;110(4):116522. doi: 10.1016/j.diagmicrobio.2024.116522. Epub 2024 Sep 7.
In vitro screening of gallium-68(Ga)-siderophores in pathogens relevant to infections is valuable for determining species specificity, their effect on cell viability, and potential clinical applications. As the recognition and internalization of siderophores relies on the presence of receptor- and/or siderophore-binding proteins, the level of uptake can vary between species. Here, we report in vitro uptake validation in Escherichia coli with its native siderophore, enterobactin (ENT) ([Ga]Ga-ENT), considering different experimental factors. Compared with other reporting methods of uptake, '% Added dose/10 CFU/mL (% AD/10 CFU/mL),' considering the total viable count, showed a better comparison among microbial species. Later, in vitro screening with [Ga]Ga-desferrioxamine B (DFO-B) showed high uptake by Staphylococcus aureus and S. epidermidis; moderate uptake by Pseudomonas aeruginosa; poor uptake by E. coli, Candida albicans, and Aspergillus fumigatus; and no uptake by Enterococcus faecalis and C. glabrata. Except for S. epidermidis, [Ga]Ga-DFO-B did not reduce the cell viability.
在与感染相关的病原体中进行镓-68（Ga）-铁载体的体外筛选对于确定物种特异性、它们对细胞活力的影响以及潜在的临床应用是有价值的。由于铁载体的识别和内化依赖于受体和/或铁载体结合蛋白的存在，因此在不同物种之间摄取水平可能会有所不同。在这里，我们报告了在大肠杆菌中用其天然铁载体肠菌素（ENT）（[Ga]Ga-ENT）进行的体外摄取验证，同时考虑了不同的实验因素。与其他摄取报告方法相比，“添加剂量的百分比/每 10^6 个菌落形成单位（% AD/10^6 CFU/mL）”，考虑到总活菌计数，在微生物物种之间显示出更好的比较。随后，用[Ga]Ga-去铁胺 B（DFO-B）进行的体外筛选显示金黄色葡萄球菌和表皮葡萄球菌具有高摄取率；铜绿假单胞菌具有中等摄取率；大肠杆菌、白色念珠菌和烟曲霉摄取率低；粪肠球菌和光滑念珠菌则没有摄取。除表皮葡萄球菌外，[Ga]Ga-DFO-B 不会降低细胞活力。
