Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland.
Sci Rep. 2020 Jan 28;10(1):1364. doi: 10.1038/s41598-020-58415-7.
The insecticides we use for agriculture and for vector control often arrive in water bodies, where mosquito larvae may be exposed to them. Not only will they then likely affect the development of the larvae, but their effects may carry over to the adults, potentially affecting their capacity at transmitting infectious diseases. Such an impact may be expected to be more severe when mosquitoes are undernourished. In this study, we investigated whether exposing larvae of the mosquito Anopheles gambiae to a sub-lethal dose of permethrin (a pyrethroid) and forcing them to compete for food would affect the immune response of the adults. We found that a low dose of permethrin increased the degree to which individually reared larvae melanised a negatively charged Sephadex bead and slowed the replication of injected Escherichia coli. However, if mosquitoes had been reared in groups of three (and thus had been forced to compete for food) permethrin had less impact on the efficacy of the immune responses. Our results show how larval stressors can affect the immune response of adults, and that the outcome of exposure to insecticides strongly depends on environmental conditions.
我们用于农业和病媒控制的杀虫剂经常会进入水体，而蚊子幼虫可能会暴露在这些杀虫剂中。这不仅可能会影响幼虫的发育，而且它们的影响还可能会延续到成虫，潜在地影响它们传播传染病的能力。当蚊子营养不良时，这种影响可能会更加严重。在这项研究中，我们调查了将疟蚊幼虫 Anopheles gambiae 暴露于亚致死剂量的拟除虫菊酯（一种除虫菊酯）并迫使它们争夺食物是否会影响成虫的免疫反应。我们发现，低剂量的拟除虫菊酯会增加单独饲养的幼虫使带负电荷的 Sephadex 珠黑化的程度，并减缓注射的大肠杆菌的复制。但是，如果蚊子是在三组中饲养的（因此被迫争夺食物），拟除虫菊酯对免疫反应的效果的影响就会较小。我们的研究结果表明幼虫压力源如何影响成虫的免疫反应，以及暴露于杀虫剂的结果强烈取决于环境条件。
