Introduction – state hypothesis or problem and its scope (<1 page) Regenerative medicine aims to restore or establish normal function by replacing or regenerating human cells, tissue, or organs (Dunnill). Cell-based therapies are integral in regenerative medicine for the inherent ability of stem cells (SCs) to differentiate into specific cell types (Sedgley & Botero). SCs can be isolated during embryogenesis (embryonic SCs), or in postnatal tissues, and they present two distinctive characteristics: the ability to continuously self-renew and the ability to differentiate into multiple cell types. Embryonic SCs are of particular interest because they have such properties as the ability to differentiate …show more content…
Many adult SCs are derived from the cranial neural crest during development and contribute to the formation of condensed dental mesenchyme, dental papilla, odontoblasts, dental pulp, cementum, periodontal ligaments, and chondrocytes (Chai, fate of mammalian). Adult SCs have been identified in tissues including skin, intestine, liver, brain, and bone marrow. An adult SC can divide and create another cell like itself, as well as a more differentiated cell. However the capacity for differentiation into other cell types is limited and is known as being multipotent. Multipotency is a unique feature of adult SCs compared with the pluripotentcey found in embryonic SCs (Arthur, adult human dental pulp stem cells) (Arthur, implanted adult human). Although early research suggested that adult SCs were limited in the types of tissues they produced, it is increasingly apparent that adult stem cells have greater plasticity than previously thought and can generate a tissue different to the site from which they were originally isolated (Arthur, adult human dental pulp stem cells) (Arthur, implanted adult human). Bone marrow SCs are the most comprehensively studied due to a variety of cell surface and genetic markers which have helped define various stages of their differentiation during hematopoiesis (Fischbach). Therefore it has been established that bone marrow is also the primary …show more content…
DPSCs were the first TDSCs discovered in 2000, found inside dental pulp (Gronthos). DPSCs have the ability to differentiate into several kinds of cells and tissues including osteoblast, smooth muscle cells, adipocyte-like cells, neuron, dentin, and dentin-pulp-like complex (Saito, Tooth-derived update). Their multipotency, proliferation rate, availability, and cell number have been demonstrated to be greater than those of BMSCs (D. L. Alge, Donor matched comparison). Originally it was shown that BMSCs were capable of differentiating into adipocytes, but DPSCs failed to form lipid-laden adipocytes in vitro (Gronthos). However, recently DPSCs have demonstrated they can differentiate into adipocyte cells when additional supplements are added to the adipogenic induction medium (Gronthos 2002) (Patil). Also, DPSCs are shown to have chondrogenic potentials in vitro (D. L. Alge, Donor matched comparison) and when transplanted in vivo, some clones differentiate into aligned odontoblast-like cells (Gronthos, Gronthos 2002). DPSCs can also form reparative dentin-like tissue on the surface of human dentin in vivo (Batouli). One study found that DPSCs maintain their MSC characteristics