Immature but not mature CD11c⁺ DCs carry the osteoclastogenic potential. Freshly purified CD11c⁺ DCs (immature) or bacteria Aggregatibactor actinomycetemcomitans (Aa)–treated DCs for 24 or 48 hours (mature) were cultured with 30 to 100 ng/mL soluble receptor activator nb NFKB ligand (sRANKL) in the presence of 10 μg/mL Aa sonicated Ag (see Alnaeeli⁴ ). On day 5, the total number of TRAP⁺ multinucleated DC-derived OCs developed per unit area were quantified, using the protocol reported previously⁴  where the results are shown as mean plus or minus SE with *P = .001 (N = 5 experiments), and DC-only and DC + Aa as negative controls and Splenocytes + ConA as positive control.