Modulation of Osteoclast Differentiation and Function by the New Members of the Tumor Necrosis Factor Receptor and Ligand Families

I. Introduction II.Role of Osteoblasts/Stromal Cells in Osteoclast Differentiation and Function A. Origin of osteoclasts B. Stimulation of osteoclast differentiation by osteoblasts/stromal cells C. Stimulation of osteoclast function by osteoblasts/ stromal cells III.New Members of the Tumor Necrosis Factor (TNF) Receptor and Ligand Families A. Osteoprotegerin (OPG) B. Osteoclast differentiation factor (ODF) and stromal osteoclast-forming activity