Differentiation potential of STRO-1+ dental pulp stem cells changes during cell passaging

<p>Abstract</p> <p>Background</p> <p>Dental pulp stem cells (DPSCs) can be driven into odontoblast, osteoblast, and chondrocyte lineages in different inductive media. However, the differentiation potential of naive DPSCs after serial passaging in the routine culture system has not been fully elucidated.</p> <p>Results</p> <p>DPSCs were isolated from human/rat dental pulps by the magnetic activated cell sorting based on STRO-1 expression, cultured and passaged in the conventional culture media. The biological features of STRO-1⁺DPSCs at the 1^stand 9^thpassages were investigated. During the long-term passage, the proliferation ability of human STRO-1⁺DPSCs was downregulated as indicated by the growth kinetics. When compared with STRO-1⁺DPSCs at the 1^stpassage (DPSC-P1), the expression of mature osteoblast-specific genes/proteins (alkaline phosphatase, bone sialoprotein, osterix, and osteopontin), odontoblast-specific gene/protein (dentin sialophosphoprotein and dentin sialoprotein), and chondrocyte-specific gene/protein (type II collagen) was significantly upregulated in human STRO-1⁺DPSCs at the 9^thpassage (DPSC-P9). Furthermore, human DPSC-P9 cells in the mineralization-inducing media presented higher levels of alkaline phosphatase at day 3 and day 7 respectively, and produced more mineralized matrix than DPSC-P9 cells at day 14. <it>In vivo </it>transplantation results showed that rat DPSC-P1 cell pellets developed into dentin, bone and cartilage structures respectively, while DPSC-P9 cells can only generate bone tissues.</p> <p>Conclusions</p> <p>These findings suggest that STRO-1⁺DPSCs consist of several interrelated subpopulations which can spontaneously differentiate into odontoblasts, osteoblasts, and chondrocytes. The differentiation capacity of these DPSCs changes during cell passaging, and DPSCs at the 9^thpassage restrict their differentiation potential to the osteoblast lineage <it>in vivo</it>.</p

Dental Pulp Stem Cell (DPSC) Isolation, Characterization, and Differentiation

3siDental pulp stem cells (DPSC) have been proposed as an alternative to pluripotent stem cells to study multilineage differentiation in vitro and for therapeutic application. Standard culture media for isolation and expansion of stem cells includes animal sera or animal-derived matrix components (e.g., Matrigel ®). However, animal-derived reagents raise significant concerns with respect to the translational ability of these cells due to the possibility of infection and/or severe immune reaction. For these reasons clinical grade substitutes to animal components are needed in order for stem cells to reach their full therapeutic potential. In this chapter we detail a method for isolation and proliferation of DPSC in a chemically defi ned medium containing a low percentage of human serum. We demonstrate that in this defi ned culture medium a 1.25 % human serum component sufficiently replaces fetal bovine serum. This method allows for isolation of a morphologically and phenotypically uniform population of DPSCs from dental pulp tissue. DPSCs represent a rapidly proliferating cell population that readily differentiates into the osteoblastic, neuronal, myocytic, and hepatocytic lineages. This multilineage capacity of these DPSCs suggests that they may have a more broad therapeutic application than lineage-restricted adult stem cell populations such as mesenchymal stem cells. Further the culture protocol presented here makes these cells more amenable to human application than current expansion techniques for other pluripotent stem cells (embryonic stem cell lines or induced pluripotent stem cells).nonenoneFerro F.; Spelat R.; Baheney C.S.Ferro, F.; Spelat, R.; Baheney, C. S

Pulp tissue from primary teeth: new source of stem cells

SHED (stem cells from human exfoliated deciduous teeth) represent a population of postnatal stem cells capable of extensive proliferation and multipotential differentiation. Primary teeth may be an ideal source of postnatal stem cells to regenerate tooth structures and bone, and possibly to treat neural tissue injury or degenerative diseases. SHED are highly proliferative cells derived from an accessible tissue source, and therefore hold potential for providing enough cells for clinical applications. In this review, we describe the current knowledge about dental pulp stem cells and discuss tissue engineering approaches that use SHED to replace irreversibly inflamed or necrotic pulps with a healthy and functionally competent tissue that is capable of forming new dentin