Application of 460 nm visible light for the elimination of Candida albicans in vitro and in vivo

Abstract

The aim of the present study was to investigate the eradicating effects of 460 nm blue light (BL) on Candida albicans in vitro and in C. albicans-infected skin wounds in a mouse model. In the present study, the antifungal effects of irradiation with BL on C. albicans in vitro and in vivo were investigated. C. albicans colonies and cell numbers were investigated using the spread plate method and flow cytometry respectively following treatment with BL irradiation. In order to determine whether BL can eradicate C. albicans cells within biofilms, an in vitro C. albicans biofilm model was established, and the effect of BL was subsequently investigated using a confocal laser scanning microscope and a Live/Dead staining kit. Furthermore, a mouse skin wound infection model infected with C. albicans was established. Wound healing rates and histological examinations were determined 0, 3, 7, 10 and 14 days post-wounding. The results revealed that C. albicans was eradicated by BL in a dose-dependent manner, with a minimum fluence of 60 J/cm2. Irradiation with BL almost completely eradicated C. albicans when the light fluence was 240 J/cm2. C. albicans inside biofilms was also eradicated and biofilms were destroyed following BL irradiation at 240 J/cm2. In addition, BL was revealed to significantly suppress C. albicans infection in vivo. Irradiation with BL promoted the wound healing of C. albicans infected-skin wounds in a mouse model. In conclusion, the results of the present study demonstrated that 460 nm BL may eradicate planktonic and biofilm C. albicans in vitro, and represents a novel therapeutic strategy for the treatment of C. albicans infections in vivo.