Molecular and Cellular Immunoregulation Section, Laboratory of Immune System Biology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, 20892, USA.
Cell Mol Immunol. 2019 Mar;16(3):225-235. doi: 10.1038/s41423-019-0210-8. Epub 2019 Feb 21.
The type 2 immune response is critical for host defense against large parasites such as helminths. On the other hand, dysregulation of the type 2 immune response may cause immunopathological conditions, including asthma, atopic dermatitis, rhinitis, and anaphylaxis. Thus, a balanced type 2 immune response must be achieved to mount effective protection against invading pathogens while avoiding immunopathology. The classical model of type 2 immunity mainly involves the differentiation of type 2 T helper (Th2) cells and the production of distinct type 2 cytokines, including interleukin-4 (IL-4), IL-5, and IL-13. Group 2 innate lymphoid cells (ILC2s) were recently recognized as another important source of type 2 cytokines. Although eosinophils, mast cells, and basophils can also express type 2 cytokines and participate in type 2 immune responses to various degrees, the production of type 2 cytokines by the lymphoid lineages, Th2 cells, and ILC2s in particular is the central event during the type 2 immune response. In this review, we discuss recent advances in our understanding of how ILC2s and Th2 cells orchestrate type 2 immune responses through direct and indirect interactions.
2 型免疫反应对于宿主防御大型寄生虫（如蠕虫）至关重要。另一方面，2 型免疫反应的失调可能导致免疫病理学状况，包括哮喘、特应性皮炎、鼻炎和过敏反应。因此，必须实现平衡的 2 型免疫反应，以在避免免疫病理学的同时对入侵病原体产生有效的保护。2 型免疫的经典模型主要涉及 2 型辅助性 T 细胞（Th2）的分化和特定 2 型细胞因子的产生，包括白细胞介素-4（IL-4）、IL-5 和 IL-13。最近，人们认识到 2 型固有淋巴细胞（ILC2）是另一种重要的 2 型细胞因子来源。尽管嗜酸性粒细胞、肥大细胞和嗜碱性粒细胞也可以表达 2 型细胞因子并在不同程度上参与 2 型免疫反应，但淋巴谱系、Th2 细胞和 ILC2 产生 2 型细胞因子是 2 型免疫反应中的核心事件。在这篇综述中，我们讨论了最近在理解 ILC2 和 Th2 细胞如何通过直接和间接相互作用来协调 2 型免疫反应方面的进展。
