Thapa Vaskar, Keller Nancy P, Roossinck Marilyn J
Department of Plant Pathology and Environmental Microbiology, Center for Infectious Disease Dynamics, Pennsylvania State Universitygrid.29857.31, University Park, Pennsylvania, USA.
Department of Medical Microbiology and Immunology, Department of Bacteriology, University of Wisconsin, Madison, Wisconsin, USA.
mSphere. 2022 Apr 27;7(2):e0102221. doi: 10.1128/msphere.01022-21. Epub 2022 Mar 21.
White-nose syndrome (WNS), responsible for the mass mortality of North American bats, lacks economically viable and practical models for infection, the causative agent of WNS. Not only are many susceptible North American insectivorous bats nearing extinction and, thus, scarce for experimental studies, but they are difficult to care for and maintain in captivity because of their specialized habitats and diets. In this study, we explored porcine ears as a potential substrate for studying infection development and the dynamics of growth in the laboratory. Porcine ear skin shares many tissue-level similarities with bat skin and is a readily available resource. We found the porcine ear model provided a substrate faithfully mimicking external colony morphology and internal histology similar to what is seen with infections in bat wing membranes. This model provided a major advance by distinguishing virulence attributes between a wild-type strain harboring a partitivirus common to all North American strains of the fungus and an isogenic virus-cured strain. ImageJ analysis showed that the cured strain was reduced significantly in ability to produce hyphal cover and showed less spore production on porcine skin. Taken together, these results strengthen our previous finding that the partitivirus infection has a role in WNS and provides a valuable model host tool in understanding virulence factors for therapeutic application. This work describes an important insight into the role of partitivirus in fungal biology and provides a model system for studying white-nose syndrome in bats, which has decimated North American populations.
白鼻综合征（WNS）导致了北美蝙蝠的大量死亡，目前缺乏针对该疾病病原体感染的经济可行且实用的模型。不仅许多易感染的北美食虫蝙蝠濒临灭绝，因此难以用于实验研究，而且由于其特殊的栖息地和饮食习性，它们在圈养环境中也很难照料和饲养。在本研究中，我们探索了猪耳作为在实验室中研究感染发展和生长动态的潜在基质。猪耳皮肤与蝙蝠皮肤在组织层面有许多相似之处，且是一种容易获取的资源。我们发现猪耳模型提供了一种基质，能如实模拟外部菌落形态和内部组织学，类似于在蝙蝠翼膜感染中所见的情况。该模型通过区分携带一种所有北美真菌菌株共有的分节段病毒的野生型菌株和同基因病毒清除菌株之间的毒力属性，取得了重大进展。ImageJ分析表明，清除病毒的菌株在猪皮肤上产生菌丝覆盖的能力显著降低，且孢子产量也较少。综上所述，这些结果强化了我们之前的发现，即分节段病毒感染在白鼻综合征中起作用，并为理解治疗应用中的毒力因子提供了一个有价值的模型宿主工具。这项工作描述了对分节段病毒在真菌生物学中的作用的重要见解，并为研究已使北美蝙蝠种群数量锐减的白鼻综合征提供了一个模型系统。
