Artículos científicos año 2012

Cryopreserved dental pulp tissues of exfoliated deciduous teeth is a feasible stem cell resource for regenerative medicine. Ma L, Makino Y, Yamaza H, Akiyama K, Hoshino Y, Song G, Kukita T, Nonaka K, Shi S, Yamaza T. PLoS One. 2012;7(12):e51777.

Abstract

Human exfoliated deciduous teeth have been considered to be a promising source for regenerative therapy because they contain unique postnatal stem cells from human exfoliated deciduous teeth (SHED) with self-renewal capacity, multipotency and immunomodulatory function. However preservation technique of deciduous teeth has not been developed. This study aimed to evaluate that cryopreserved dental pulp tissues of human exfoliated deciduous teeth is a retrievable and practical SHED source for cell-based therapy. SHED isolated from the cryopreserved deciduous pulp tissues for over 2 years (25-30 months) (SHED-Cryo) owned similar stem cell properties including clonogenicity, self-renew, stem cell marker expression, multipotency, in vivo tissue regenerative capacity and in vitro immunomodulatory function to SHED isolated from the fresh tissues (SHED-Fresh). To examine the therapeutic efficacy of SHED-Cryo on immune diseases, SHED-Cryo were intravenously transplanted into systemic lupus erythematosus (SLE) model MRL/lpr mice. Systemic SHED-Cryo-transplantation improved SLE-like disorders including short lifespan, elevated autoantibody levels and nephritis-like renal dysfunction. SHED-Cryo amended increased interleukin 17-secreting helper T cells in MRL/lpr mice systemically and locally. SHED-Cryo-transplantation was also able to recover osteoporosis bone reduction in long bones of MRL/lpr mice. Furthermore, SHED-Cryo-mediated tissue engineering induced bone regeneration in critical calvarial bone-defect sites of immunocompromised mice. The therapeutic efficacy of SHED-Cryo transplantation on immune and skeletal disorders was similar to that of SHED-Fresh. These data suggest that cryopreservation of dental pulp tissues of deciduous teeth provide a suitable and desirable approach for stem cell-based immune therapy and tissue engineering in regenerative medicine.

http://www.ncbi.nlm.nih.gov/pubmed/23251621

Identification, isolation, characterization, and banking of human dental pulp stem cells. Tirino V, Paino F, De Rosa A, Papaccio G. Methods Mol Biol. 2012;879:443-63.

Abstract

Dental pulp stem cells (DPSCs) can be found within the "cell rich zone" of the dental pulp. Their embryonic origin, from neural crests, explains their multipotency. Up to now, it has been demonstrated that these cells are capable of producing bone tissue, both in vitro and in vivo, as well as a simil-dentin tissue, in vitro. In addition, it has been reported that these cells differentiate into adipocytes, endotheliocytes, melanocytes, neurons, and glialcells and can be easily cryopreserved and stored for long periods of time and retain their multipotency and bone-producing capacity. Moreover, recent attention has been focused on tissue engineering and on the properties of these cells: several scaffolds have been used to promote 3D tissue formation and studies have demonstrated that DPSCs show good adherence and bone tissue formation on microconcavity surface textures, adult bone tissue with good vascularization has been obtained in grafts. Interestingly, they seem to possess immunoprivileges as they can be grafted into allogenic tissues and seem to exert anti-inflammatory abilities, like many other mesenchymal stem cells. Their recent use in clinical trials for bone repair enforces the notion that DPSCs can be used successfully in patients. Therefore, their isolation, selection, differentiation, and banking are of great importance. The isolation technique used in most laboratories is based on the use of flow cytometry with cell sorter termed FACS (fluorescent activated cell sorter). It is now important to obtain new methods/protocols to select and isolate stem cells without staining by fluorescent markers or use of magnetic beads. These new procedures should be based on biophysical differences among the different cell populations in order to obtain interesting peculiarities for implementation in biomedical/clinical laboratories. It is emphasized that the new methods must address simplicity and short times of preparation and use of samples, complete sterility of cells, the potential disposable, low cost and complete maintenance of the viability, and integrity of the cells with real-time response for subsequent applications in the biomedical/clinical/surgical fields.

http://www.ncbi.nlm.nih.gov/pubmed/22610575

Isolation, characterization and comparative differentiation of human dental pulp stem cells derived from permanent teeth by using two different methods. Karamzadeh R, Eslaminejad MB, Aflatoonian R. J Vis Exp. 2012 Nov 24;(69).

Abstract

Developing wisdom teeth are easy-accessible source of stem cells during the adulthood which could be obtained by routine orthodontic treatments. Human pulp-derived stem cells (hDPSCs) possess high proliferation potential with multi-lineage differentiation capacity compare to the ordinary source of adult stem cells; therefore, hDPSCs could be the good candidates for autologous transplantation in tissue engineering and regenerative medicine. Along with these benefits, possessing the mesenchymal stem cells (MSC) features, such as immunolodulatory effect, make hDPSCs more valuable, even in the case of allograft transplantation. Therefore, the primary step for using this source of stem cells is to select the best protocol for isolating hDPSCs from pulp tissue. In order to achieve this goal, it is crucial to investigate the effect of various isolation conditions on different cellular behaviors, such as their common surface markers & also their differentiation capacity. Thus, here we separate human pulp tissue from impacted third molar teeth, and then used both existing protocols based on literature, for isolating hDPSCs i.e. enzymatic dissociation ofpulp tissue (DPSC-ED) or outgrowth from tissue explants (DPSC-OG). In this regards, we tried to facilitate the isolation methods by using dentaldiamond disk. Then, these cells characterized in terms of stromal-associated Markers (CD73, CD90, CD105 & CD44), hematopoietic/endothelial Markers (CD34, CD45 & CD11b), perivascular marker, like CD146 and also STRO-1. Afterwards, these two protocols were compared based on the differentiation potency into odontoblasts by both quantitative polymerase chain reaction (qPCR) & Alizarin Red Staining. qPCR were used for the assessment of the expression of the mineralization-related genes (alkaline phosphatase; ALP, matrix extracellular phosphoglycoprotein; MEPE & dentin sialophosphoprotein; DSPP).

http://www.ncbi.nlm.nih.gov/pubmed/23208006

Dental pulp of the third molar: a new source of pluripotent-like stem cells. Atari M, Gil-Recio C, fabregat M, García-Fernandez D, Barajas M, Carrasco MA, Jung HS, Alfaro FH, Casals N, Prosper F, Ferrés-Padró E, Giner L. J Cell Sci. 2012 Jul 15;125(Pt 14):3343-56.

Abstract

Dental pulp is particularly interesting in regenerative medicine because of the accessibility and differentiation potential of the tissue. Dental pulp has an early developmental origin with multi-lineage differentiation potential as a result of its development during childhood and adolescence. However, no study has previously identified the presence of stem cell populations with embryonic-like phenotypes in human dental pulp from the third molar. In the present work, we describe a new population of dental pulp pluripotent-like stem cells (DPPSCs) that were isolated by culture in medium containing LIF, EGF and PDGF. These cells are SSEA4(+), OCT3/4(+), NANOG(+), SOX2(+), LIN28(+), CD13(+), CD105(+), CD34(-), CD45(-), CD90(+), CD29(+), CD73(+), STRO1(+) and CD146(-), and they show genetic stability in vitro based on genomic analysis with a newly described CGH technique. Interestingly, DPPSCs were able to form both embryoid-body-like structures (EBs) in vitro and teratoma-like structures that contained tissues derived from all three embryonic germ layers when injected in nude mice. We examined the capacity of DPPSCs to differentiate in vitro into tissues that have similar characteristics to mesoderm, endoderm and ectoderm layers in both 2D and 3D cultures. We performed a comparative RT-PCR analysis of GATA4, GATA6, MIXL1, NANOG, OCT3/4, SOX1 and SOX2 to determine the degree of similarity between DPPSCs, EBs and human induced pluripotent stem cells (hIPSCs). Our analysis revealed that DPPSCs, hIPSC and EBs have the same gene expression profile. Because DPPSCs can be derived from healthy human molars from patients of different sexes and ages, they represent an easily accessible source of stem cells, which opens a range of new possibilities for regenerative medicine.

http://www.ncbi.nlm.nih.gov/pubmed/22467856

Dental Stem cells and their sources. Sedgley CM, Botero TM. Dent Clin North Am. 2012 Jul;56(3):549-61. doi: 10.1016/j.cden.2012.05.004. Epub 2012 Jun 23. Review.

Abstract

The search for more accessible mesenchymal stem cells than those found in bone marrow has propelled interest in dental tissues. Human dental stem/progenitor cells (collectively termed dental stem cells [DSCs]) that have been isolated and characterized include dental pulp stem cells, stem cells from exfoliated deciduous teeth, stem cells from apical papilla, periodontal ligament stem cells, and dental follicle progenitor cells. Common characteristics of these cell populations are the capacity for self-renewal and the ability to differentiate into multiple lineages. In vitro and animal studies have shown that DSCs can differentiate into osseous, odontogenic, adipose, endothelial, and neural-like tissues.

http://www.ncbi.nlm.nih.gov/pubmed/22835537

Stem cells of the dental pulp. Ranganathan K, Lakshminarayanan V. Indian J Dent Res. 2012 Jul-Aug;23(4):558.

Abstract

Stem cells of the dental pulp are a population of postnatal stem cells with multilineage differentiation potential. These cells are derived from the neural ectomesenchyme, similar to most craniofacial tissues, and specific niches in the pulp have been identified. Since the isolation of dental pulp stem cells (DPSC) and stem cells from exfoliating deciduous teeth (SHED), numerous studies have attempted to define and characterize these cells, and embryonic stem cell features have been reported in both DPSC and SHED. These cells have a vast repertoire of differentiation - osteogenic, odontogenic, myogenic, adipogenic, neurogenic, and melanocytic, and have even demonstrated transdifferentiation to corneal cells and islet cells of pancreas. The combined advantages of multipotency/pluripotency and the relative ease of access of pulp tissue for autologous use render DPSC/ SHED attractive options in regenerative dentistry and medicine. This review gives a bird's eye view of current knowledge with respect to stem cells from the dental pulp.

http://www.ijdr.in/article.asp?issn=0970-9290;year=2012;volume=23;issue=...