Richards Stephanie L, Pesko Kendra, Alto Barry W, Mores Christopher N
University of Florida, Institute of Food and Agricultural Sciences, Department of Entomology and Nematology, Florida Medical Entomology Laboratory, 200 9th St. S.E., Vero Beach, FL 32962, USA.
Virus Res. 2007 Nov;129(2):224-7. doi: 10.1016/j.virusres.2007.06.019. Epub 2007 Aug 7.
The increased difficulty and expense of using live animals for delivering infectious blood meals in arthropod-borne virus vector competence experiments has resulted in an increase in the use of artificial feeding systems. Compared to live hosts, artificial systems require higher viral titers to attain mosquito infection, thereby limiting the utility of such systems with low or moderate titer virus stocks. Based on the report that freshly propagated virus is more infectious than previously frozen virus, we determined whether such a preparation would enhance the ability to use artificial feeding systems. Culex quinquefasciatus and Aedes aegypti mosquitoes were offered blood in artificial membrane feeders containing freshly collected or previously frozen St. Louis encephalitis and dengue serotype-2 viruses (family Flaviviridae), respectively. Infection rates and estimates of vector competence were significantly lower (P<0.05) for mosquitoes feeding on blood meals containing frozen-thawed compared to freshly collected virus. We indicate that the use of freshly propagated virus in artificial feeding systems can be an effective blood delivery method for low-titer viruses and viruses that are otherwise inefficient at infecting vectors in such systems. Fresh viruses used in artificial feeding systems may be a viable alternative to the heavily regulated and expensive use of live animals.
在节肢动物传播病毒载体能力实验中，使用活体动物提供感染性血餐的难度和成本增加，导致人工饲养系统的使用有所增加。与活体宿主相比，人工系统需要更高的病毒滴度才能使蚊子感染，从而限制了此类系统在低滴度或中等滴度病毒毒株中的应用。基于新鲜繁殖的病毒比先前冷冻的病毒更具传染性的报告，我们确定这种制剂是否会增强使用人工饲养系统的能力。分别向致倦库蚊和埃及伊蚊提供含有新鲜采集或先前冷冻的圣路易斯脑炎病毒和登革热2型病毒（黄病毒科）的人工膜饲养器中的血液。与以含有新鲜采集病毒的血餐为食的蚊子相比，以含有冻融病毒的血餐为食的蚊子的感染率和载体能力估计值显著更低（P<0.05）。我们表明，在人工饲养系统中使用新鲜繁殖的病毒对于低滴度病毒以及在这类系统中感染载体效率较低的病毒而言，可能是一种有效的血液输送方法。人工饲养系统中使用的新鲜病毒可能是严格监管且成本高昂的活体动物使用的可行替代方案。
