A popular view in the current academic circle is that invertebrates have no adaptive immunity. However, the immune memory and specificity of invertebrates pose a serious challenge to this view and constitute immune priming based on innate immunity. The Down syndrome cell adhesion molecule (Dscam) gene of invertebrates, with approximately 10,000 alternatively spliced isoforms, has a unique characteristic: it specifically binds to different types of bacteria and promotes cell phagocytosis; owing to its antibody-like function, Dscam is a key candidate protein for immune priming. However, the high molecular diversity of Dscam and the gaps and inconsistencies in the existing research make the study of regulation of immune priming by Dscam challenging. In recent years, significant research has been conducted on the Dscam-regulated immune functions in insects and crustaceans, providing preliminary results for Dscam-regulated innate immunity and immune priming, but some important questions remain unresolved. In this review, we summarize the existing knowledge about Dscam-regulated immunity and discuss three yet unanswered questions, the study of which may improve the understanding of the role of Dscam-regulated immune priming in invertebrates.

当前学术界的一个流行观点是，无脊椎动物没有适应性免疫。然而，无脊椎动物的免疫记忆和特异性对这一观点提出了严峻挑战，构成了基于先天免疫的免疫启动。唐氏综合症细胞粘附分子（Dscam) 无脊椎动物的基因，大约有 10,000 个可变剪接的亚型，具有独特的特性：它特异性结合不同类型的细菌并促进细胞吞噬作用；由于其类似抗体的功能，Dscam 是免疫启动的关键候选蛋白。然而，Dscam的高分子多样性以及现有研究的空白和不一致使得Dscam对免疫启动的调控研究具有挑战性。近年来，针对Dscam调控昆虫和甲壳类动物的免疫功能进行了大量研究，为Dscam调控的先天免疫和免疫启动提供了初步结果，但一些重要问题仍未解决。在这篇综述中，我们总结了关于 Dscam 调节免疫的现有知识，并讨论了三个尚未解决的问题，