Department of Orthopaedic Surgery, Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Bone and Cartilage Regenerative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Int J Mol Sci. 2022 Jan 20;23(3):1104. doi: 10.3390/ijms23031104.
While type 2 immunity has traditionally been associated with the control of parasitic infections and allergic reactions, increasing evidence suggests that type 2 immunity exerts regulatory functions on inflammatory diseases such as arthritis, and also on bone homeostasis. This review summarizes the current evidence of the regulatory role of type 2 immunity in arthritis and bone. Key type 2 cytokines, like interleukin (IL)-4 and IL-13, but also others such as IL-5, IL-9, IL-25, and IL-33, exert regulatory properties on arthritis, dampening inflammation and inducing resolution of joint swelling. Furthermore, these cytokines share anti-osteoclastogenic properties and thereby reduce bone resorption and protect bone. Cellular effectors of this action are both T cells (i.e., Th2 and Th9 cells), but also non-T cells, like type 2 innate lymphoid cells (ILC2). Key regulatory actions mediated by type 2 cytokines and immune cells on both inflammation as well as bone homeostasis are discussed.
虽然 2 型免疫通常与寄生虫感染和过敏反应的控制有关，但越来越多的证据表明，2 型免疫对关节炎等炎症性疾病以及骨稳态发挥调节作用。本文总结了 2 型免疫在关节炎和骨骼中调节作用的现有证据。关键的 2 型细胞因子，如白细胞介素 (IL)-4 和 IL-13，但也包括其他细胞因子，如 IL-5、IL-9、IL-25 和 IL-33，对关节炎具有调节作用，可减轻炎症并诱导关节肿胀消退。此外，这些细胞因子具有抗破骨细胞生成的特性，从而减少骨吸收并保护骨骼。这种作用的细胞效应物既包括 T 细胞（即 Th2 和 Th9 细胞），也包括非 T 细胞，如 2 型先天淋巴样细胞 (ILC2)。本文讨论了 2 型细胞因子和免疫细胞在炎症和骨稳态方面的关键调节作用。
