Stem cells from exfoliated deciduous teeth (SHED) are isolated from incisors of 6- to 8-year-old children. Cells express mesenchymal surface markers and have an elevated proliferation rate and telomerase activity compared to bone marrow mesenchymal stem cells (BMMSCs). SHED cells can differentiate into osteogenic cells but have a lower capacity to differentiate into adipogenic cells, when compared to BMMSCs. Cells transplanted into immunocompromised mice form mineralized tissue. SHED cells have an immunomodulatory effect in vitro and can reverse systemic lupus erythematosus (SLE)-associated symptoms when transplanted into SLE-like mice.
Minced dental pulp tissue was digested in a solution of collagenase type I (0.2%) and dispase II (0.1%) in phosphate buffered saline (PBS) for 1 hour. Mononuclear cells (MNCs) were passed through a cell strainer (70μm) and single cell suspension was seeded on tissue culture plates and cultured in alpha modification of Eagle's medium (α-MEM) supplemented with FCS (15%), L-ascorbic acid 2-phosphate (100μM), L-glutamine (2 mM) penicillin (100 units/ml), and streptomycin (100 μg/ml). Nonadherent cells were removed by washing with PBS after 3 hours.