Department of Medical Biology, Akita University Graduate School of Medicine, Akita, Japan.
Department of Medical Biology, Akita University Graduate School of Medicine, Akita, Japan.
Allergol Int. 2021 Apr;70(2):174-180. doi: 10.1016/j.alit.2020.11.007. Epub 2020 Dec 13.
Group 2 innate lymphoid cells (ILC2s) reside in peripheral tissues such as the lungs, skin, nasal cavity, and gut and provoke innate type 2 immunity against allergen exposure, parasitic worm infection, and respiratory virus infection by producing T2 cytokines. Recent advances in understanding ILC2 biology revealed that ILC2s can be trained by IL-33 or allergic inflammation, are long-lived, and mount memory-like type 2 immune responses to any other allergens afterwards. In contrast, IL-33, together with retinoic acid, induces IL-10-producing immunosuppressive ILC2s. In this review, we discuss how the allergic cytokine milieu and other immune cells direct the generation of trained ILC2s with immunostimulatory or immunosuppressive recall capability in allergic diseases and infections associated with type 2 immunity. The molecular mechanisms of trained immunity by ILCs and the physiological relevance of trained ILC2s are also discussed.
2 型固有淋巴细胞（ILC2s）存在于肺部、皮肤、鼻腔和肠道等外周组织中，通过产生 T2 细胞因子来针对过敏原暴露、寄生虫感染和呼吸道病毒感染引发固有 2 型免疫。对 ILC2 生物学的最新研究进展揭示，ILC2s 可被 IL-33 或过敏炎症所“训练”，具有长寿命，并在随后对任何其他过敏原产生记忆样 2 型免疫反应。相比之下，IL-33 与维甲酸一起诱导产生 IL-10 的免疫抑制性 ILC2s。在这篇综述中，我们讨论了过敏性细胞因子微环境和其他免疫细胞如何在与 2 型免疫相关的过敏性疾病和感染中，指导具有免疫刺激或免疫抑制记忆能力的“训练”ILC2s 的产生。我们还讨论了 ILC 产生训练免疫的分子机制以及“训练”ILC2s 的生理相关性。
