title: T-cells and B-cells in osteoporosis.
abstract: OBJECTIVE
  Bone disease is a leading cause of fractures and continues to be a source of significant morbidity and mortality worldwide. As the underlying mechanisms of osteoporosis are elucidated, immune dysfunction continues to emerge as a key precipitating factor in multiple bone disease contexts. This review examines recent findings in the osteoimmunology field and their implications for bone disease and for novel future therapeutic approaches to rejuvenate the skeleton.
  
  
  RESULTS
  T-cells and B-cells have long been recognized to play important roles in the etiology of inflammatory bone disease; however, new findings continue to challenge our understanding of the depth of the immuno-skeletal interface. In this review, we examine recent evidence for new roles of B-cells in oestrogen deficiency bone loss; central actions of interleukin-7 in the cause of T-cell mediated tissue destruction in rheumatoid arthritis; novel RANKL-independent alveolar bone loss in periodontal infection; and a putative role for γδ T-cells in bisphosphonate-associated osteonecrosis of the jaw. Finally, evidence for novel bone anabolic activities mediated through T-cells by the CD28 antagonist CTLA-4Ig and by intermittently administered parathyroid hormone are examined.
  
  
  CONCLUSIONS
  As the field of osteoimmunology continues to mature, new interrelationships between immune cells and bone turnover continue to emerge.
authors.affiliation: aAtlanta Department of Veterans Affairs Medical Center, Decatur bDepartment of Medicine, Division of Endocrinology and Metabolism and Lipids, Emory University School of Medicine, Atlanta, Georgia, USA.
authors.forename: M Neale
authors.initials: MN
authors.lastname: Weitzmann
mesh_terms: D016301:Alveolar Bone Loss / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology; D001402:B-Lymphocytes / Q000378:metabolism*; D050071:Bone Density Conservation Agents / Q000627:therapeutic use; D001842:Bone and Bones / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology; D006801:Humans; D008336:Mandibular Diseases / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology; D010010:Osteoclasts / Q000378:metabolism; D010024:Osteoporosis / Q000276:immunology* / Q000378:metabolism / Q000503:physiopathology; D013601:T-Lymphocytes / Q000378:metabolism*
chemical_list: D050071:Bone Density Conservation Agents