Department of Osteoimmunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Department of Immunology, Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
Semin Immunopathol. 2019 Sep;41(5):619-626. doi: 10.1007/s00281-019-00755-2. Epub 2019 Sep 24.
Bone homeostasis depends on a balance between osteoclastic bone resorption and osteoblastic bone formation. Bone cells are regulated by a variety of biochemical factors, such as hormones and cytokines, as well as various types of physical stress. The immune system affects bone, since such factors are dysregulated under pathologic conditions, including infection. The bone marrow, one of the primary lymphoid organs, provides a special microenvironment that supports the function and differentiation of immune cells and hematopoietic stem cells (HSCs). Thus, bone cells contribute to immune regulation by modulating immune cell differentiation and/or function through the maintenance of the bone marrow microenvironment. Although osteoblasts were first reported as the population that supports HSCs, the role of osteoblast-lineage cells in hematopoiesis has been shown to be more limited than previously expected. Osteoblasts are specifically involved in the differentiation of lymphoid cells under physiological and pathological conditions. It is of critical importance how bone cells are modified during inflammation and/or infection and how such modification affects the immune system.
骨稳态依赖于破骨细胞的骨吸收和成骨细胞的骨形成之间的平衡。骨细胞受多种生化因子的调节，如激素和细胞因子，以及各种类型的物理应激。免疫系统影响骨骼，因为在包括感染在内的病理条件下，这些因素会失调。骨髓是主要的淋巴器官之一，为免疫细胞和造血干细胞（HSCs）的功能和分化提供了特殊的微环境。因此，骨细胞通过维持骨髓微环境来调节免疫细胞的分化和/或功能，从而参与免疫调节。虽然成骨细胞最初被报道为支持 HSCs 的群体，但成骨细胞谱系细胞在造血中的作用比以前预期的要有限。成骨细胞在生理和病理条件下专门参与淋巴细胞的分化。在炎症和/或感染期间，骨细胞如何被修饰以及这种修饰如何影响免疫系统是至关重要的。
