Chou Brandon, Krishna Katherine, Durkee Heather, Echeverri Tribin Felipe, Ahmed Anam, Lai James, Aguilar Mariela C, Ferreira Braulio C L B, Leblanc Roger M, Flynn Harry W, Amescua Guillermo, Parel Jean-Marie, Miller Darlene
Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America.
Ophthalmic Biophysics Center, Bascom Palmer Eye Institute, Department of Ophthalmology, University of Miami Miller School of Medicine, Miami, FL, United States of America.
J Photochem Photobiol B. 2025 Feb;263:113090. doi: 10.1016/j.jphotobiol.2024.113090. Epub 2024 Dec 27.
Fungal keratitis is a leading cause of corneal blindness, with current antifungal treatments having limited efficacy. One promising treatment modality is Rose Bengal (RB) photodynamic antimicrobial therapy (PDAT) that has shown mixed success against fungal keratitis. Therefore, there is a need to explore the antimicrobial efficacy of other green-light activated photosensitizers that have deep penetration in the cornea to combat the deep fungal infections, such as Erythrosin B (EB) and Eosin Y (EY).
This study will explore PDAT inhibitory effects with different photosensitizers, RB, EB, and EY against two common fungal ocular isolates, Aspergillus spp. and Fusarium spp.
Twelve fungal isolates (Fusarium spp., n = 6, Aspergillus spp., n = 6) were prepared in suspension for evaluation of growth inhibition to PDAT with three photosensitizers, EB, EY, and RB. Custom green light source (λ = 518 nm, energy density = 5.4 J/cm) was applied to the experimental groups for 15 min. Fungal growth inhibition was assessed after experimentation by analyzing the area of growth within the irradiated zone on agar plates.
All twelve fungal isolates showed no inhibition to EB, EY, and RB without irradiation. Fusarium spp. were more susceptible to PDAT than Aspergillus spp. In all Fusarium solani strains, all photosensitizers with light showed full inhibition within the 47 mm diameter irradiation zone.
EB, EY, and RB PDAT demonstrated comparable antifungal inhibition against six Fusarium ocular isolates; these findings in conjunction with the deeper tissue penetration of EB and EY, are of interest to treat more advanced and deeper cases of fungal keratitis.
真菌性角膜炎是导致角膜盲的主要原因，目前的抗真菌治疗效果有限。一种有前景的治疗方式是孟加拉玫瑰红（RB）光动力抗菌疗法（PDAT），其对真菌性角膜炎的治疗效果不一。因此，有必要探索其他能在角膜中深度渗透以对抗深部真菌感染的绿光激活光敏剂的抗菌效果，如赤藓红B（EB）和伊红Y（EY）。
本研究将探讨不同光敏剂RB、EB和EY对两种常见眼部真菌分离株曲霉属和镰刀菌属的PDAT抑制作用。
制备12株真菌分离株（镰刀菌属，n = 6；曲霉属，n = 6）的悬液，以评估三种光敏剂EB、EY和RB对PDAT的生长抑制作用。将定制的绿色光源（λ = 518 nm，能量密度 = 5.4 J/cm）应用于实验组15分钟。实验后通过分析琼脂平板上照射区域内的生长面积来评估真菌生长抑制情况。
所有12株真菌分离株在未照射时对EB、EY和RB均无抑制作用。镰刀菌属比曲霉属对PDAT更敏感。在所有茄病镰刀菌菌株中，所有带光的光敏剂在直径47 mm的照射区域内均显示出完全抑制作用。
EB、EY和RB的PDAT对6株眼部镰刀菌分离株表现出相当的抗真菌抑制作用；这些发现连同EB和EY更深的组织穿透力，对于治疗更严重和更深部的真菌性角膜炎病例具有重要意义。
