State Research Center of Virology and Biotechnology "Vector" Rospotrebnadzor, Koltsovo, Novosibirsk Region, 630559, Russia.
Novosibirsk State University, 1, Pirogova Str., Novosibirsk, 630090, Russia.
Photodiagnosis Photodyn Ther. 2021 Mar;33:102112. doi: 10.1016/j.pdpdt.2020.102112. Epub 2020 Nov 26.
Recently, the COVID-19 pandemic has spread globally, necessitating the development of new methods for its prevention and treatment. The purpose of this study was to evaluate the antiviral activity of photodynamic therapy (PDT) against SARS-CoV-2 in vitro.
Vero E6 cells and SARS-CoV-2 isolated in Russia were used for PDT with methylene blue (MB) and Radachlorin. A continuous laser with wavelength λ = 662 nm in doses of 16 J/cm and 40 J/cm laser irradiation was used for PDT of a viral suspension and SARS-CoV-2-infected cells. The direct cytopathogenic effect of SARS-CoV-2 was evaluated via light microscopy to calculate the TCID in the samples and perform statistical analysis.
Viral suspensions of SARS-CoV-2 that had a TCID greater than 10 were inactivated by PDT in the presence of MB and Radachlorin. Vero E6 cells were protected from 10 TCID of SARS-CoV-2 by PDT post infection. The range of protective concentrations was 1.0-10.0 μg/ml and 0.5-5.0 μg/ml for MB and Radachlorin, respectively. Additionally, it was found that MB and Radachlorin also possess significant antiviral activity even without PDT. The 50 % inhibitory concentration (IC) against 10 TCID of SARS-CoV-2 was found to be 0.22 and 0.33 μg/mL with the addition of MB and Radachlorin, respectively, to cells concomitantly with virus, whereas in the case of applying the photosensitizers at 3.5 h post infection, the IC was 0.6 and 2.0 μg/mL for MB and Radachlorin, respectively.
PDT shows high antiviral activity against SARS-CoV-2 when combined with MB and Radachlorin in vitro.
最近，COVID-19 疫情在全球范围内蔓延，需要开发新的预防和治疗方法。本研究的目的是评估光动力疗法（PDT）对 SARS-CoV-2 的体外抗病毒活性。
使用俄罗斯分离的 SARS-CoV-2 和 Vero E6 细胞进行光动力疗法，使用亚甲蓝（MB）和 Radachlorin。使用波长为 662nm 的连续激光，剂量为 16J/cm 和 40J/cm 激光辐照，对病毒悬浮液和 SARS-CoV-2 感染的细胞进行 PDT。通过光学显微镜评估 SARS-CoV-2 的直接细胞病变效应，计算样品中的 TCID，并进行统计分析。
在存在 MB 和 Radachlorin 的情况下，TCID 大于 10 的 SARS-CoV-2 病毒悬浮液被 PDT 灭活。Vero E6 细胞在感染后通过 PDT 得到保护，免受 10TCID 的 SARS-CoV-2 感染。MB 和 Radachlorin 的保护浓度范围分别为 1.0-10.0μg/ml 和 0.5-5.0μg/ml。此外，还发现 MB 和 Radachlorin 即使没有 PDT 也具有显著的抗病毒活性。当 MB 和 Radachlorin 与病毒同时加入细胞时，对 10TCID 的 SARS-CoV-2 的 50%抑制浓度（IC）分别为 0.22 和 0.33μg/ml，而在感染后 3.5 小时应用光敏剂时，IC 分别为 0.6 和 2.0μg/ml。
PDT 与 MB 和 Radachlorin 联合使用时，对 SARS-CoV-2 具有高抗病毒活性。
