title: Osteoclasts: more than 'bone eaters'.
abstract: As the only cells definitively shown to degrade bone, osteoclasts are key mediators of skeletal diseases including osteoporosis. Bone-forming osteoblasts, and hematopoietic and immune system cells, each influence osteoclast formation and function, but the reciprocal impact of osteoclasts on these cells is less well appreciated. We highlight here the functions that osteoclasts perform beyond bone resorption. First, we consider how osteoclast signals may contribute to bone formation by osteoblasts and to the pathology of bone lesions such as fibrous dysplasia and giant cell tumors. Second, we review the interaction of osteoclasts with the hematopoietic system, including the stem cell niche and adaptive immune cells. Connections between osteoclasts and other cells in the bone microenvironment are discussed within a clinically relevant framework.
authors.affiliation: Department of Medicine, Division of Rheumatology, Allergy, and Immunology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Julia F
authors.initials: JF
authors.lastname: Charles
authors.affiliation: Department of Medicine, Division of Rheumatology, Allergy, and Immunology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts, USA. Electronic address: aaliprantis@partners.org.
authors.forename: Antonios O
authors.initials: AO
authors.lastname: Aliprantis
mesh_terms: D000818:Animals; D016723:Bone Remodeling; D001862:Bone Resorption / Q000378:metabolism / Q000473:pathology; D001842:Bone and Bones / Q000378:metabolism / Q000473:pathology; D005357:Fibrous Dysplasia of Bone / Q000378:metabolism / Q000473:pathology; D018212:Giant Cell Tumor of Bone / Q000378:metabolism / Q000473:pathology; D006801:Humans; D010010:Osteoclasts / Q000166:cytology / Q000378:metabolism* / Q000473:pathology*; D010012:Osteogenesis; D010022:Osteopetrosis / Q000378:metabolism / Q000473:pathology; D010024:Osteoporosis / Q000378:metabolism / Q000473:pathology
keywords: PTH; bone remodeling; osteoblast; osteoclast; osteopetrosis; osteoporosis