Caratteristiche generali

• Hanno grande potenziale proliferativo• Sono capaci di autorinnovamento• Sono generalmente pluripotenti• Sono presenti in tutti gli stadi di sviluppo:

– Embrionale (ESC)– Fetale (FSC)– Adulto (ASC)

• Provvedono:– allo sviluppo embrionale e fetale – alla rigenerazione ed all’omeostasi di organi adulti

Science, Vol 282, Issue 5391, 1145-1147 , 6 November 1998

Embryonic Stem Cell Lines Derived fromHuman Blastocysts James A. Thomson, * Joseph Itskovitz-Eldor, Sander S. Shapiro, Michelle A. Waknitz, Jennifer J. Swiergiel, Vivienne S. Marshall, Jeffrey M. Jones

“…These cell lines should be useful in human developmental biology, drug discovery, and transplantation medicine.”

Cellule staminali embrionali (ESC)

Dental Tissue Mesenchimal Stem Cell

• Human Pulp Tissue (DPSC’s, post-natal dental pulp stem cells)– Gronthos et al, 2000

• Exfoliated Deciduous Teeth (SHED)– Miura et al, 2003

• Periodontal Ligament (PDLSC)– Seo et al, 2004

• Apical Papilla (SCAP)– Sonoyama et al, 2006, 2008

• Dental Follicle Precursors (DFPC)– Morsczeck et al, 2005

Dental Stem Cells

Mesenchymal stem cells are found in dental pulp, periodontal ligament, and the periosteum.10 An abundant source of these undifferentiated mesenchymal cells in permanent teeth is in the dental pulp of immature, impacted third molars.

Mesenchymal stem cells have recently been discovered in the dental pulp of deciduous teeth, known as SHED (stem cells from human exfoliated deciduous teeth).11 SHED cells are formed in the developing embryo and demonstrate greater plasticity than stem cells taken from permanent teeth, meaning that they grow and multiply more rapidly as compared to those taken from the pulp of fully developed permanent teeth.

These unique characteristics suggest that the immaturity of SHED cells shows greater potential for differentiation into a wider array of tissue types. Further, SHED cells are able to express proteins on their cell surfaces that allow them to not only differentiate into dental pulp, bone, and dentin, but also into neural and fat cells (adipocytes). In fact, SHED cells differentiate into nerve cells more readily than adult stem cells isolated from permanent teeth.

SHED cells express a variety of neural growth factors and glial cell markers that directly reflect the embryonic neural crest origin of dental pulp and suggest that they may be important for use in future nerve regeneration therapies.

11Dental stem cells are the most accessible stem cells.

They are isolated from many sources, including healthy dental pulp, periodontal ligament, bone, and the apical region of developing teeth, and can be recovered during a planned dental procedure.10

Stem cells within the pulp and at the apex of developing teeth are a valuable source of very proliferative, multipotent mesenchymal stem cells.12

Follicular tissue surrounding unerupted or impacted teeth is of ectomesenchymal origin and is also an excellent source for stem cells.11