Abstract: Provided are a peptide for inhibiting an interaction between an RANKL and an RANK consisting of an amino acid sequence of SEQ ID NO: 1 and a pharmaceutical composition for preventing or treating bone diseases including the peptide. The peptide consisting of an amino acid sequence of SEQ ID NO: 1 is not present in a cyclic shape, and has 10 or less amino acids, thereby having better biostability than a conventional peptide to inhibit an RANKL-RANK interaction, being preferable in price during synthesis, and having a better RANKL-RANK interaction inhibitory effect. For this reason, the peptide may be used as an effective component of the composition effectively inhibiting differentiation of osteoclasts. A pharmaceutical composition including the peptide is bound with the RANKL and the peptide, instead of the RANK, thereby inhibiting the interaction between the RANKL and the RANK, and thus inhibiting osteoclast differentiation.

Abstract: Provided are a peptide for inhibiting an interaction between an RANKL and an RANK consisting of an amino acid sequence of SEQ ID NO: 1 and a pharmaceutical composition for preventing or treating bone diseases including the peptide. The peptide consisting of an amino acid sequence of SEQ ID NO: 1 is not present in a cyclic shape, and has 10 or less amino acids, thereby having better biostability than a conventional peptide to inhibit an RANKL-RANK interaction, being preferable in price during synthesis, and having a better RANKL-RANK interaction inhibitory effect. For this reason, the peptide may be used as an effective component of the composition effectively inhibiting differentiation of osteoclasts. A pharmaceutical composition including the peptide is bound with the RANKL and the peptide, instead of the RANK, thereby inhibiting the interaction between the RANKL and the RANK, and thus inhibiting osteoclast differentiation.

Abstract: Provided is a purified, negative regulator of osteoclast differentiation and bone resorption, specifically LRRc17. Further provided are methods and compositions for treating degenerative bone disorders, and treatments and prophylactic approaches for regulating bone resorption, and for decreasing or inhibiting the excessive bone loss associated with abnormal or excessive generation of or activity of osteoclasts.

Abstract: Provided is a purified, negative regulator of osteoclast differentiation and bone resorption, specifically LRRc17. Further provided are methods and compositions for treating degenerative bone disorders, and treatments and prophylactic approaches for regulating bone resorption, and for decreasing or inhibiting the excessive bone loss associated with abnormal or excessive generation of or activity of osteoclasts.

Abstract: This invention relates to methods and compositions that modulate the activity of cells, such as osteoclast cells, involved in the growth, development, repair, degradation and homeostasis of bone tissue. The compositions may therefore by used to modulate such processes and to treat bone growth related disorders (for example, osteoporosis and osteopetrosis). In particular, the invention provides a novel polypeptide, referred to as the Osteoclast Associated Receptor or OSCAR, that is specifically expressed by oteoclast cells and modulates osteoclast cell activity. OSCAR nucleic acids (including vectors), fusion polypeptides and OSCAR specific antibodies are also provided, as well as diagnostic and screening assays using such nucleic acids, polypeptide and antibodies.