Department of Clinical Chemistry and Molecular Diagnostics, Philipps-University, Marburg, Germany.
J Immunol. 2011 Jan 1;186(1):13-8. doi: 10.4049/jimmunol.1002483.
The term osteoimmunology is coined for molecular and cellular cross talk between the skeletal and immune system. Immunomodulatory signals have long been implicated as key regulators of bone metabolism. Recently, osteoclast-associated receptor (OSCAR), an IgG-like receptor, has been identified as an important osteoimmunological mediator. OSCAR expression in bone is highly conserved across different species, and the molecule is an important costimulatory receptor for osteoclast differentiation through activation of NFATc1. In humans, OSCAR is expressed by macrophages, monocytes, and monocyte-derived dendritic cells and modulates the response of the innate and adaptive immune systems by promoting cell activation and maturation, Ag presentation, and proinflammatory circuits. Human studies indicate that OSCAR may contribute to the pathogenesis and severity of osteoporosis and rheumatoid arthritis. In this paper, we review the structure-function relationship, expression pattern, and physiological role of OSCAR in osteoimmunology and summarize its potential implications for human diseases.
骨免疫学这一术语是为骨骼系统和免疫系统之间的分子和细胞串扰而创造的。免疫调节信号长期以来一直被认为是骨代谢的关键调节剂。最近，破骨细胞相关受体（OSCAR），一种 IgG 样受体，已被确定为重要的骨免疫学介质。不同物种的骨中 OSCAR 的表达高度保守，该分子是通过激活 NFATc1 促进破骨细胞分化的重要共刺激受体。在人类中，OSCAR 由巨噬细胞、单核细胞和单核细胞衍生的树突状细胞表达，并通过促进细胞激活和成熟、Ag 呈递和促炎回路来调节先天和适应性免疫系统的反应。人类研究表明，OSCAR 可能导致骨质疏松症和类风湿关节炎的发病机制和严重程度。本文综述了 OSCAR 在骨免疫学中的结构-功能关系、表达模式和生理作用，并总结了其对人类疾病的潜在意义。
