Modulation of bne development

A method of modulating bone development comprising administering an effective amount of an agent that modulates a CD200 receptor to a cell or animal in need thereof.

A method for identifying a compound that modulates bone development comprising:

• (a) incubating a test compound with a bone cell expressing a CD200 receptor;
• and
• (b) determining the effect of the compound on the CD200 receptor activity or expression and comparing with a control, wherein a change in the CD200 receptor activity or expression as compared to the control indicates that the test compound may modulate bone development.

A method of identifying a CD200R agonist useful in stimulating bone development comprising the steps of:

• (a) incubating a test compound with a bone cell expressing a CD200R;
• and
• (b) determining whether or not the test compound stimulates a CD200R, wherein stimulation of the CD200R indicates that the test compound is a CD200R agonist that may be useful in stimulating bone development.

A screening assay for identifying an antagonist of a CD200 receptor useful in inhibiting bone development comprising the steps of:

• (a) incubating a test compound with a CD200 receptor;
• and
• (b) determining whether or not the test compound inhibits the CD200 receptor, wherein inhibition of the CD200R indicates that the compound is a CD200R antagonist and may be useful in inhibiting bone development.

A method of identifying substances which bind with a CD200 receptor, comprising the steps of:

• (a) incubating a bone cell expressing a CD200 receptor and a test substance, under conditions which allow for formation of a complex, and
• (b) assaying for complexes of the CD200 receptor and the test substance, for free substance, and for non-complexed CD200 receptor, wherein the presence of complexes indicates that the test substance is capable of binding the CD200 receptor.