Department of Biology, Temple University, Philadelphia, PA19122, USA.
Saft America Inc., 13575 Waterworks St., Jacksonville, FL32221, USA.
Microsc Microanal. 2020 Apr;26(2):267-274. doi: 10.1017/S1431927620001270.
Biological transmission of arthropod-borne viruses (arboviruses) to vertebrate hosts by hematophagous insects poses a global threat because such arboviruses can result in a range of serious public health infectious diseases. Sindbis virus (SINV), the prototype Alphavirus, was used to track infections in the posterior midgut (PMG) of Aedes aegypti adult mosquitoes. Females were fed viremic blood containing a virus reporter, SINV [Thosea asigna virus-green fluorescent protein (TaV-GFP)], that leaves a fluorescent signal in infected cells. We assessed whole-mount PMGs to identify primary foci, secondary target tissues, distribution, and virus persistence. Following a viremic blood meal, PMGs were dissected and analyzed at various days of post blood-feeding. We report that virus foci indicated by GFP in midgut epithelial cells resulted in a 9.8% PMG infection and a 10.8% dissemination from these infected guts. The number of virus foci ranged from 1 to 3 per individual PMG and was more prevalent in the PMG-middle > PMG-frontal > PMG-caudal regions. SINV TaV-GFP was first observed in the PMG (primary target tissue) at 3 days post blood-feeding, was sequestered in circumscribed foci, replicated in PMG peristaltic muscles (secondary target tissue) following dissemination, and GFP was observed to persist in PMGs for 30 days postinfection.
节肢动物传播的虫媒病毒（arboviruses）通过吸血昆虫传播给脊椎动物宿主，这构成了全球性的威胁，因为这些arboviruses 可导致一系列严重的公共卫生传染病。辛德毕斯病毒（SINV）是正粘病毒科的原型病毒，曾被用于追踪埃及伊蚊成蚊的后中肠（PMG）感染。雌性蚊子吸食含有病毒报告基因的病毒血症血液，即 SINV [Thosea asigna 病毒-绿色荧光蛋白（TaV-GFP）]，该病毒在感染细胞中留下荧光信号。我们评估了整体 PMG，以确定主要感染灶、次级靶组织、分布和病毒持续时间。在吸食带病毒血症的血液后，我们在不同的取食后天数对 PMG 进行解剖和分析。我们报告称，GFP 指示的病毒感染灶导致 9.8%的 PMG 感染和 10.8%的从这些感染肠道的传播。每个个体 PMG 的病毒感染灶数量从 1 到 3 个不等，并且在 PMG-中部>PMG-额部>PMG-尾部区域更为普遍。SINV TaV-GFP 在取食后 3 天首次在 PMG（主要靶组织）中观察到，在传播后被局限在特定的感染灶中，在 PMG 蠕动肌（次级靶组织）中复制，GFP 在 PMG 中可观察到持续 30 天。
