Sprangers Sara, Schoenmaker Ton, Cao Yixuan, Everts Vincent, de Vries Teun J
Department of Oral Cell Biology and Functional Anatomy, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan, Amsterdam, The Netherlands.
Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), University of Amsterdam and VU University Amsterdam, MOVE Research Institute Amsterdam, Gustav Mahlerlaan, Amsterdam, The Netherlands.
J Cell Physiol. 2016 Jun;231(6):1249-60. doi: 10.1002/jcp.25220. Epub 2015 Nov 9.
Osteoclasts are bone-degrading cells that are formed through fusion of their monocytic precursors. Three distinct subsets of monocytes have been identified in human peripheral blood: classical, intermediate, and non-classical monocytes. They are known to play different roles in physiology and pathology, but their capacity to differentiate into osteoclasts and whether inflammatory cytokines influence this differentiation is unknown. We hypothesized that classical, intermediate, and non-classical monocytes generate functionally different osteoclasts and that they respond in different ways to the inflammatory cytokine interleukin-17A (IL-17A). To investigate this, the different monocyte subsets were isolated from human peripheral blood and osteoclastogenesis was induced with the cytokines M-CSF and RANKL, with or without IL-17A. We found that all subsets are able to differentiate into osteoclasts in vitro, and that both osteoclastogenesis and subsequent bone resorption was distinctly affected by IL-17A. Osteoclastogenesis and bone resorption by osteoclasts derived from classical monocytes remained unaffected by IL-17A, while osteoclast formation from intermediate monocytes was inhibited by the cytokine. Surprisingly, bone resorption by osteoclasts derived from intermediate monocytes remained at similar levels as control cultures, indicating an increased bone resorbing activity by these osteoclasts. Limited numbers of osteoclasts were formed from non-classical monocytes on bone and no bone resorption was detected, which suggest that these cells belong to a cell lineage different from the osteoclast. By providing more insight into osteoclast formation from human blood monocytes, this study contributes to the possible targeting of specific osteoclast precursors as a therapeutic approach for diseases associated with inflammatory bone loss.
破骨细胞是通过其单核前体细胞融合形成的骨降解细胞。在人类外周血中已鉴定出三种不同的单核细胞亚群:经典单核细胞、中间单核细胞和非经典单核细胞。已知它们在生理和病理过程中发挥不同作用,但它们分化为破骨细胞的能力以及炎性细胞因子是否影响这种分化尚不清楚。我们假设经典单核细胞、中间单核细胞和非经典单核细胞产生功能不同的破骨细胞,并且它们对炎性细胞因子白细胞介素-17A(IL-17A)的反应方式不同。为了研究这一点,从人类外周血中分离出不同的单核细胞亚群,并用细胞因子M-CSF和RANKL诱导破骨细胞生成,同时添加或不添加IL-17A。我们发现所有亚群在体外都能够分化为破骨细胞,并且IL-17A对破骨细胞生成和随后的骨吸收均有明显影响。源自经典单核细胞的破骨细胞的破骨细胞生成和骨吸收不受IL-17A影响,而中间单核细胞的破骨细胞形成则受到该细胞因子的抑制。令人惊讶的是,源自中间单核细胞的破骨细胞的骨吸收水平与对照培养物相似,这表明这些破骨细胞的骨吸收活性增加。在骨上由非经典单核细胞形成的破骨细胞数量有限,未检测到骨吸收,这表明这些细胞属于与破骨细胞不同的细胞谱系。通过更深入地了解人类血液单核细胞形成破骨细胞的过程,本研究有助于将特定破骨细胞前体作为与炎性骨质流失相关疾病的治疗方法进行靶向治疗。