The Steinernema carpocapsae-Xenorhabdus nematophila association is a nematobacterial complex used in biological control of insect crop pests. The infection success of this dual pathogen strongly depends on its interactions with the host's immune system. Here, we used the lepidopteran pest Spodoptera frugiperda to analyze the respective impact of each partner in the induction of its immune responses. First, we used previously obtained RNAseq data to construct the immunome of S. frugiperda and analyze its induction. We then selected representative genes to study by RT-qPCR their induction kinetics and specificity after independent injections of each partner. We showed that both X. nematophila and S. carpocapsae participate in the induction of stable immune responses to the complex. While X. nematophila mainly induces genes classically involved in antibacterial responses, S. carpocapsae induces lectins and genes involved in melanization and encapsulation. We discuss putative relationships between these differential inductions and the pathogen immunosuppressive strategies.

该斯carpocapsae -嗜线虫致病杆菌的关联是在昆虫作物害虫的生物控制中使用的复杂的nematobacterial。这种双重病原体的感染成功很大程度上取决于它与宿主免疫系统的相互作用。在这里，我们使用鳞翅目害虫草地贪夜蛾来分析每个伙伴在诱导其免疫反应方面的各自影响。首先，我们使用先前获得的 RNAseq 数据构建草地贪夜蛾的免疫组并分析其诱导。然后我们选择了代表性基因，通过 RT-qPCR 研究它们在每个伙伴独立注射后的诱导动力学和特异性。我们证明了X. nematophila和S. carpocapsae参与对复合物的稳定免疫反应的诱导。虽然X. nematophila主要诱导经典地参与抗菌反应的基因，但S. carpocapsae诱导凝集素和参与黑化和封装的基因。我们讨论了这些差异诱导与病原体免疫抑制策略之间的假定关系。