A compound having a sugar chain having a structure represented by the following formula as a basic structure (however, sialic acid does not exist at two non-reducing ends of the following structure, and x and y each independently represents 3 or 4). Dendritic cell immunoreceptor activator, dendritic cell immune receptor activation method, osteoclast formation inhibitor, osteoclast formation inhibitor, dendritic cell differentiation / proliferation inhibitor, tree A method for inhibiting dendritic cell differentiation / proliferation, a cytokine production inhibitor, a method for inhibiting cytokine production, a treatment method, and a screening method are provided.下記式で表される構造を基本構造とする糖鎖(ただし、下記構造の2つの非還元末端にシアル酸が存在せず、x及びyはそれぞれ独立に3又は4を表す。)を有する化合物を有効成分として含む、樹状細胞免疫受容体活性化剤、樹状細胞免疫受容体活性化方法、破骨細胞形成抑制剤、破骨細胞形成抑制方法、樹状細胞分化・増殖阻害剤、樹状細胞分化・増殖阻害方法、サイトカイン産生抑制剤、サイトカイン産生抑制方法、治療方法及びスクリーニング方法を提供する。