Bone is a metabolically active tissue that undergoes continuous remodeling by two counteracting processes, bone formation and bone resorption. These events are strongly linked and tightly regulated to maintain skeletal homeostasis. The bone cells responsible for the dual processes include the bone-resorbing cells, for example, the osteoclasts, which are differentiated cells derived from hematopoietic cells of the monocyte-macrophage lineage, and bone forming cells, for example, the osteoblasts, which are of mesenchymal origin. Alteration of the differentiation/activity of osteoclasts as well as osteoblasts leads to bone diseases. Recently, the key role of immune cells in pathologies with bone involvement is emerging from the literature. Thus, a better understanding of the mechanisms governing the role of immune systems in bone diseases has potential for developing new therapeutic strategies for the treatment of disorders.

We invite investigators to contribute original research articles as well as review articles that will stimulate the continuing efforts to understand the prominent role of immune system in the alteration of bone remodeling, thus favoring bone disease development.

Potential topics include, but are not limited to:

• The role of immune system in osteotropic solid and haematological malignancies
• Immunoregulation of pathological bone loss in postmenopausal and secondary osteoporosis
• Mechanisms of altered bone remodeling in autoimmune and inflammatory diseases
• Immune system involvement in extra calcification sites (cardiac valves and vessels)
• Latest therapeutic strategies targeting bone disease linked to immune cells