[Osteocytes and osteonetwork].

Osteocytes are the most abundant osteolineage cells in the bone tissue, and they control the balance of activity between osteoblasts and osteoclasts in bone metabolism. Recent studies have revealed that the bone equipped with osteocytes controls not only bone marrow hematopoiesis but also regulates the functions of remote organs/tissues such as thymus and fat. Communications of bone cells with hematopoiesis, immunity and energy metabolism are overviewed.