National Institute of Public Health, Center for Research on Infectious Diseases, Santa María Ahuacatitlán, Cuernavaca, 62100, Morelos, Mexico.
Postgraduate in Biological Sciences, National Autonomous University of Mexico, Av. Ciudad Universitaria 3000, Coyoacán, C.P. 04510, Mexico.
Sci Rep. 2020 Apr 21;10(1):6723. doi: 10.1038/s41598-020-63402-z.
Several studies have observed that the immune response in insects can be conserved, a phenomenon known as immune priming, which has been mostly tested in adult stages. However, it is unknown if induction of immune priming in larval stages protects against dengue virus (DENV) infections in adult mosquitoes. In this work, we primed larval instar 3 of Aedes aegypti with inactive dengue virus, producing adult mosquitoes with i) an enhanced antiviral-immune response; ii) a reduction in the load and replication of RNA of dengue virus (DENV); iii) a decline in viral infective particles production. Adult mosquitoes previously primed during larval stages over-expressed RNA interference (RNAi) markers Argonaute-2 (AGO-2) and Dicer-2 (DCR-2). We also observed inter-individual variations of DENV infection in adult mosquitoes, indicating a heterogeneous response to DENV infection in the same mosquito strain. However, mosquitoes primed during larval stages appear to control the infection, reducing the viral load. The over-expression of interferon-like factors (VAGO) and AGO-2 in the pupa stage suggests a fast activation of antiviral mechanisms after immune priming in larvae, creating a condition in which adult mosquitoes are resistant to the pathogen in the posterior exposure.
已有多项研究观察到昆虫的免疫反应具有保守性，这种现象被称为免疫致敏，其大多在成虫阶段进行测试。然而，尚不清楚幼虫期的免疫致敏是否能保护成年蚊子免受登革热病毒（DENV）感染。在这项工作中，我们用非活性登革热病毒致敏埃及伊蚊幼虫 3 龄期，产生的成年蚊子具有：i）增强的抗病毒免疫反应；ii）减少登革热病毒（DENV）的 RNA 载量和复制；iii）减少病毒感染性颗粒的产生。在幼虫期预先致敏的成年蚊子过度表达 RNA 干扰（RNAi）标志物 Argonaute-2（AGO-2）和 Dicer-2（DCR-2）。我们还观察到成年蚊子中 DENV 感染的个体间差异，表明在同一蚊子品系中对 DENV 感染存在异质性反应。然而，在幼虫期预先致敏的蚊子似乎控制了感染，降低了病毒载量。在蛹期干扰素样因子（VAGO）和 AGO-2 的过度表达表明在幼虫期免疫致敏后抗病毒机制的快速激活，使成年蚊子在后暴露期对病原体具有抗性。
