Siglec-15, a member of the sialic acid-binding lectin, is a novel regulator for osteoclast differentiation

► Siglec-15 was identified as a gene overexpressed in giant cell tumor. ► Siglec-15 mRNA expression increased in association with osteoclast differentiation. ► Polyclonal antibody to Siglec-15 inhibited osteoclast differentiation in vitro.