BMSC-sEVs integrated into hydrogel systems effectively reduced TRAP+-positive cell numbers and inhibited periodontitis progression through regulation of the Osteoprotegerin/Receptor activator of nuclear factor kappa-B ligand/Receptor activator of nuclear factor kappa-B (OPG-RANKL-RANK) signaling pathway and macrophage polarization modulation[68]. The gene discussed is ACP5; the disease is periodontitis.