Role of Extracellular Vesicles of Stem Cells from Human Exfoliated Deciduous Teeth in Osteogenesis

The tissue regenerative potential of the liquid component of mesenchymal stem cells has gained significant attention. Stem cells from human exfoliated deciduous teeth-conditioned medium (SHED-CM), which is often extracted during orthodontic treatment, promotes bone regeneration. However, further investigation is warranted to determine which component of SHED-CM affects bone regeneration. Therefore, we focused on the extracellular vesicles contained in SHED-CM (SHED-EVs) and aimed to study their effects on osteoblasts. SHED-EVs were isolated using a pellet-down EV extraction kit and identified using transmission electron microscopy and NanoSight. SHED-EVs were added to human calvarial osteoblasts (HCOs), and cell proliferation and migration ability were examined with Incucyte^® and BrdU. Alkaline phosphatase (ALP) expression was confirmed using real-time PCR and ALP quantification. The bone differentiation potential was examined using Alizarin Red S (ARS) staining. SHED-EVs promoted proliferation and migration of HCOs. Real-time PCR and ALP quantification results demonstrated that HCOs cultured with SHED-EVs exhibited increased ALP expression. ARS staining revealed that SHED-EVs promoted bone differentiation of HCOs. These results suggest that SHED-EVs promote cell proliferation and migration and bone regeneration of osteoblasts, highlighting their potential in the development of bone regeneration therapies.