ELZA Institute, Dietikon, Switzerland.
Institute of Medical Microbiology, University of Zurich, Zurich, Switzerland.
Transl Vis Sci Technol. 2023 Sep 1;12(9):14. doi: 10.1167/tvst.12.9.14.
To investigate and compare the efficacy of high-fluence accelerated photoactivated chromophore for keratitis-corneal cross-linking (PACK-CXL) using either riboflavin/ultraviolet (UV)-A light or rose bengal/green light to treat Staphylococcus aureus or Pseudomonas aeruginosa infections in an ex vivo porcine cornea model.
One hundred and seventeen ex vivo porcine corneas were injected with clinical isolates of S. aureus or P. aeruginosa, divided into eight groups, and cultured for 24 hours. Then, either riboflavin with UV-A light irradiation (30 mW/cm2; 8 minutes, 20 seconds; 15 J/cm2) or rose bengal with green light irradiation (15 mW/cm2, 16 minutes, 40 seconds; 15 J/cm2) was applied; unirradiated infected groups served as controls. All corneas were incubated for another 24 hours. Next, corneal buttons were obtained and vortexed to release the bacterial cells. The irradiated and unirradiated solutions were then plated and incubated on agar plates. The amount of colony-forming units was quantified and the bacterial killing ratios (BKRs) resulting from different PACK-CXL protocols relative to non-treated controls were calculated.
Riboflavin/UV-A light PACK-CXL resulted in median BKRs of 52.8% and 45.8% in S. aureus and P. aeruginosa, respectively, whereas rose bengal/green light PACK-CXL resulted in significantly greater BKRs of 76.7% and 81.0%, respectively (both P < 0.01).
Both accelerated PACK-CXL protocols significantly decreased S. aureus and P. aeruginosa bacterial loads. Comparing the riboflavin/UV-A light and rose bengal/green light PACK-CXL approaches in the same experimental setup may help develop strain-specific and depth-dependent PACK-CXL approaches that could be used alongside the current standard of care.
Our study used an animal model to gain insight into the efficacy of high-fluence accelerated PACK-CXL using either riboflavin/UV-A light or rose bengal/green light to treat Staphylococcus aureus or Pseudomonas aeruginosa infections.
使用核黄素/紫外线（UV）-A 光或孟加拉玫瑰红/绿光，研究并比较高流量加速光激活染色质交联（PACK-CXL）治疗金黄色葡萄球菌或铜绿假单胞菌感染的疗效，以治疗金黄色葡萄球菌或铜绿假单胞菌感染。在体外猪角膜模型中。
将 117 个体外猪角膜用金黄色葡萄球菌或铜绿假单胞菌的临床分离株注射，分为 8 组，培养 24 小时。然后，用核黄素和 UV-A 光照射（30 mW/cm2；8 分钟 20 秒；15 J/cm2）或孟加拉玫瑰红和绿光照射（15 mW/cm2，16 分钟 40 秒；15 J/cm2）；未照射的感染组作为对照。所有角膜再孵育 24 小时。然后，获得角膜按钮并涡旋以释放细菌细胞。然后对照射和未照射的溶液进行平板培养。定量平板上的菌落形成单位数量，并计算不同 PACK-CXL 方案相对于未处理对照的细菌杀伤率（BKR）。
核黄素/UV-A 光 PACK-CXL 分别导致金黄色葡萄球菌和铜绿假单胞菌的中位 BKR 为 52.8%和 45.8%，而孟加拉玫瑰红/绿光 PACK-CXL 分别导致显著更高的 BKR 为 76.7%和 81.0%（均 P < 0.01）。
两种加速 PACK-CXL 方案均显著降低金黄色葡萄球菌和铜绿假单胞菌的细菌负荷。在相同的实验设置中比较核黄素/UV-A 光和孟加拉玫瑰红/绿光 PACK-CXL 方法可能有助于开发针对特定菌株和深度的 PACK-CXL 方法，可与当前的标准护理方法一起使用。
Diana
