RAPID: Investigating molecular-level responses of coronavirus under UVC irradiation

冠状病毒如SARS-CoV 1、MERS-CoV和SARS-CoV 2（引起COVID-19的病毒）在过去二十年中引起了几次全球性的呼吸道疾病大流行。冠状病毒感染的主要暴露途径是通过皮肤接触受污染的表面，然后触摸面部区域。迫切需要有效和安全的表面消毒方法来对抗冠状病毒。 这在医疗环境中尤其如此，其中可重复使用的个人防护设备（PPE）、医疗器械和手术室中的表面需要反复消毒。除了临床环境，随着控制大流行的干预措施的放松，公共交通和商业商店等高接触区域迫切需要保持无病毒状态。目前使用漂白剂和酒精等化学品的表面消毒方法可能导致材料腐蚀和化学残留物。表面消毒的一种潜在解决方案是使用紫外线（UV）设备。紫外线已被证明对其他病毒有效，但由于其独特的分子结构，必须优化以治疗SARS-CoV 2和其他冠状病毒。该研究旨在了解来自不同来源的紫外线（包括新推出的UVLED）如何破坏SARS-CoV 2涂层中的核酸和蛋白质。研究结果将为紫外线设备的设计和操作提供指导，以消毒受污染的表面，这将有助于对抗COVID-19全球大流行和未来冠状病毒引起的呼吸道疫情。发射UVC辐射（200-280 nm）的紫外光（UV）装置已被证明通过破坏核酸和蛋白质而对病毒消毒有效。暴露于无包膜病毒的紫外线显示，DNA/RNA损伤是病毒灭活的主要原因，在265 nm附近具有峰值效力，而蛋白质损伤在紫外线光谱的高（~280 nm）和低（240 nm）端的波长处是重要的。冠状病毒是一种有包膜的非节段正义RNA病毒，由于其独特的分子结构，可能对UVC照射产生不同的反应。本项目的目标是研究在220至280 nm波长的UVC照射下冠状病毒的灭活动力学以及RNA和结构蛋白的损伤。鼠冠状病毒和鼠肝炎病毒（MHV）将在本项目中用作代表性冠状病毒和人冠状病毒的替代物。冠状病毒的UVC灭活效率和动力学将通过将MHV污染的表面样品和水样品暴露在具有三种不同UV源的实验室规模准直光束装置中的UVC照射下来确定：UVLED系统（在255、265和/或285 nm处发射）、KrCl准分子灯（222 nm）和低压UV灯（254 nm）。将使用长程逆转录定量聚合酶链反应研究不同波长UVC照射下MHV的RNA损伤，并使用肽液相色谱串联质谱法评估蛋白质损伤。病毒分子结构和紫外线灭活效率和机制之间的基本科学关系将通过比较冠状病毒的紫外线作用与先前研究中使用的无包膜病毒的紫外线作用来评估。这些发现将导致产生明确的紫外线-该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响进行评估，被认为值得支持审查标准。

Coronaviruses such as SARS-CoV1, MERS-CoV, and SARS-CoV2 (the virus responsible for COVID-19), have caused several global pandemics of respiratory diseases over the last two decades. A primary exposure pathway for coronavirus infections is through skin contact with contaminated surfaces followed by touching of facial areas. Effective and safe methods for surface disinfection against coronaviruses is urgently needed. This is particularly true in healthcare settings where reusable personal protective equipment (PPE), medical instruments, and surfaces in operating rooms need repeated disinfection. Beyond clinical settings, high-touch areas such as public transportation and commercial shops have an urgent need to stay virus-free as intervention efforts to control the pandemic are eased. Current surface disinfection methods using chemicals like bleach and alcohol can result in material corrosion and chemical residuals. A potential solution for surface disinfection is the use of ultraviolet light (UV) devices. UV light has been proven to be effective against other viruses but must be optimized to treat SARS-CoV2 and other coronaviruses because of their unique molecular structure. The study aims to understand how UV light from different sources (including newly available UVLEDs) damage the nucleic acid and proteins in SARS-CoV2 coatings. The findings will provide guidance for UV device design and operation for disinfecting contaminated surfaces, which will help in the fight against the COVID-19 global pandemic and future coronavirus-caused respiratory outbreaks. Ultraviolet light (UV) devices emitting UVC irradiation (200-280 nm) have proven to be effective for virus disinfection by damaging nucleic acids and proteins. UV exposure to non-enveloped viruses revealed that DNA/RNA damage is the primary cause for virus inactivation, with a peak efficacy around 265nm, whereas protein damage is important at wavelengths at the high (~280 nm) and low (240 nm) ends of the UV spectrum. Coronavirus, which is an enveloped, non-segmented positive-sense RNA virus, may respond to UVC irradiation differently due to its unique molecular structure. The goal of this project is to investigate inactivation kinetics and RNA and structural protein damage of coronavirus under UVC irradiation across wavelengths from 220 to 280 nm. Murine coronavirus and murine hepatitis virus (MHV) will be used as a representative coronavirus and a surrogate of human coronavirus in this project. The UVC inactivation efficiencies and kinetics of coronavirus will be determined by exposing MHV contaminated surface samples and water samples under UVC irradiation in a bench-scale collimated beam apparatus with three different UV sources: a UVLED system (emitting at 255, 265, and/or 285 nm), a KrCl excimer lamp (222 nm), and a low pressure UV lamp (254 nm). The RNA damage of MHV under UVC irradiation across wavelengths will be investigated using long range reverse transcript quantitative polymerase chain reaction and the protein damage will be assessed using peptide liquid chromatography tandem mass spectrometry. The fundamental scientific relationship between virus molecular structure and UV inactivation efficiency and mechanisms will be evaluated by comparing the UV action of coronavirus to those of nonenveloped viruses used in previous studies. These findings will lead to generation of definitive UV-disinfection kinetics of coronavirus on surfaces to inform proper operation and use of UV devices and support the engineering of new disinfection devices that will serve as urgent and effective interventions during relevant public health emergencies.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.