Work

Antimicrobial Blue Light for Treatment of Candida albicans Keratitis: Efficacy in Ex Vivo Rabbit Corneas and Safety Evaluation in Retinal Cells In Vitro

Year: 2025

Type: article

Abstract: ABSTRACT Objectives To assess the efficacy of antimicrobial blue light (aBL) in managing Candida albicans keratitis in rabbit corneas ex vivo and safety to retinal cells in vitro. Methods C. albicans (strain CEC‐749) suspensions were exposed to aBL with different light irradiance to assess the susceptibility of C. albicans to aBL. An ex vivo C. albicans keratitis model using rabbit corneas infected with a bioluminescent strain CEC‐749 was developed. aBL was delivered topically to the infected corneas after fungal inoculation at varying irradiances. Bioluminescent imaging was used to track corneal infection progression in real‐time. To evaluate the toxicity of aBL to the retinal cells, photoreceptors (661W) and retinal pigment epithelium cells (ARPE‐19) were exposed to aBL in vitro, with cell viability and apoptosis assessed. The viability change of 661W cells under intermittent irradiation of aBL is determined. Results At varying irradiances of 25, 50, and 100 mW/cm 2 and a constant 405 nm blue light exposure of 216 J/cm 2 , 3.39‐, 3.67‐, and 2.83‐log10 CFU of C. albicans were inactivated in suspensions, respectively. Bioluminescence imaging revealed that C. albicans keratitis was fully developed in ex vivo rabbit corneas 24 h following fungal inoculation. After exposure to 288 J/cm 2 aBL, the fungal burden in the 6, 18, and 24 h‐infected rabbit corneas was reduced by approximately 1.57‐, 2.18‐, and 1.47‐log10, as determined by bioluminescence imaging. The viability and apoptosis of both 661W and ARPE‐19 cells were significantly affected by continuous aBL delivery at 32.43 J/cm 2 . Intermittent irradiation with a total exposure of 37.50 J/cm 2 , administered as 12.50 J/cm 2 per irradiation session with 2 h intervals for three sessions, did not affect the viability of 661W cells. Conclusions aBL is a potential treatment for C. albicans keratitis. The intermittent irradiation approach using aBL to treat fungal keratitis could be a safety modality for clinical application.

Source: Lasers in Surgery and Medicine

DOI: 10.1002/lsm.70082

Authors: Jingjing Jiang, Quan Yan, Yuchen Wang, Fang Wei, Jingyang Feng, Hong Zhu

Institutions: Shanghai Jiao Tong University, Shanghai First People's Hospital, Shanghai Eye Disease Prevention & Treatment Center, University of Shanghai for Science and Technology

Language: English

Topic: Ocular Infections and Treatments

Subfield: Ophthalmology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: bronze

Funders: National Natural Science Foundation of China, Center for Visual Science