Lan Yu, Lu Sha, Zheng Bowen, Tang Zengqi, Li Jiahao, Zhang Junmin
Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, 107 West Yanjiang Road, Guangzhou, 510120, China.
Department of Dermatology, The Eighth Affiliated Hospital, Sun Yat-sen University, 3025 Shennan Road Central, Shenzhen, 518033, China.
Lasers Surg Med. 2021 Jul;53(5):722-730. doi: 10.1002/lsm.23343. Epub 2020 Nov 8.
Trichosporiosis is an opportunistic infection that includes superficial infections, white piedra, hypersensitivity pneumonitis, and invasive trichosporonosis. The effect of antifungal agents against these infections is largely weakened by drug resistance and biofilms-related virulence. Photodynamic therapy (PDT) is a new therapeutic approach developed not only to combat cancerous lesions but also to treat infectious diseases such as fungal infections. However, there are few studies on the antimicrobial mechanism of 5-aminolevulinic acid PDT (ALA-PDT) in treating Trichosporon. In this work, we explored the possibility of combining ALA-PDT with an antifungal agent to enhance the therapeutic efficacy of Trichosporon asahii (T. asahii) in a clinical setting and in vitro.
STUDY DESIGN/MATERIALS AND METHODS: The biofilms of T. asahii were constructed by a 96-well plate-based method in vitro. The planktonic and adherent T. asahii were exposed to different concentrations of photosensitizers and different light doses. After PDT treatment, counting colony-forming units and tetrazolium (XTT) reduction assay were used to estimate the antifungal efficacy. The minimal inhibitory concentration of itraconazole before and after PDT treatment was determined by the broth dilution method, and XTT viability assay was used to detect and evaluate the synergistic potential of ALA-PDT and itraconazole combinations in inhibiting biofilms. Scanning electron microscopy (SEM) was performed to assess the disruption of biofilms.
Using combination therapy, we have successfully treated a patient who had a T. asahii skin infection. Further in vitro studies showed that the antifungal effect of ALA-PDT on planktonic and adherent T. asahii was dependent on the concentration of ALA and light dosages used. We also found that the sensitivity of both planktonic and biofilm cells to itraconazole were increased after ALA-PDT. Synergistic effect were observed for biofilms in ALA-PDT and itraconazole-combined treatment. The disruption of biofilms was confirmed by SEM, suggesting that ALA-PDT effectively damaged the biofilms and the destruction was further enhanced by ALA-PDT combination of antifungal agents.
In conclusion, these data suggest that ALA-PDT could be an alternative strategy for controlling infections caused by Trichosporon. The combination therapy of ALA-PDT with itraconazole could result in increased elimination of planktonic cells and biofilms compared with single therapy. All these findings indicate that it could be a promising treatment against trichosporonosis. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.
毛孢子菌病是一种机会性感染，包括浅表感染、白念珠菌病、过敏性肺炎和侵袭性毛孢子菌病。耐药性和生物膜相关毒力极大地削弱了抗真菌药物对这些感染的治疗效果。光动力疗法（PDT）是一种新的治疗方法，不仅用于对抗癌性病变，还用于治疗真菌感染等传染病。然而，关于5-氨基酮戊酸光动力疗法（ALA-PDT）治疗毛孢子菌的抗菌机制的研究很少。在这项研究中，我们探讨了将ALA-PDT与抗真菌药物联合使用以提高在临床环境和体外治疗阿萨希毛孢子菌（T. asahii）疗效的可能性。
研究设计/材料与方法：体外采用基于96孔板的方法构建阿萨希毛孢子菌生物膜。将浮游和附着的阿萨希毛孢子菌暴露于不同浓度的光敏剂和不同光剂量下。PDT治疗后，采用菌落形成单位计数和四氮唑（XTT）还原试验评估抗真菌疗效。采用肉汤稀释法测定PDT治疗前后伊曲康唑的最低抑菌浓度，并采用XTT活力试验检测和评估ALA-PDT与伊曲康唑联合抑制生物膜的协同潜力。进行扫描电子显微镜（SEM）观察以评估生物膜的破坏情况。
采用联合治疗，我们成功治疗了一名患有阿萨希毛孢子菌皮肤感染的患者。进一步的体外研究表明，ALA-PDT对浮游和附着的阿萨希毛孢子菌的抗真菌作用取决于所用ALA的浓度和光剂量。我们还发现，ALA-PDT后浮游和生物膜细胞对伊曲康唑的敏感性均增加。在ALA-PDT与伊曲康唑联合治疗中观察到生物膜有协同作用。SEM证实了生物膜的破坏，表明ALA-PDT有效地破坏了生物膜，并且抗真菌药物与ALA-PDT联合进一步增强了这种破坏。
总之，这些数据表明ALA-PDT可能是控制毛孢子菌感染的一种替代策略。与单一疗法相比，ALA-PDT与伊曲康唑联合治疗可增加浮游细胞和生物膜的清除。所有这些发现表明，它可能是治疗毛孢子菌病的一种有前景的方法。激光外科医学。©2020威利期刊有限责任公司。
