This Article Abstract Figures Only Full Text (PDF) Data Supplement Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Hu, B. Articles by Lesot, H. Search for Related Content PubMed PubMed Citation Articles by Hu, B. Articles by Lesot, H. Social Bookmarking                         What's this?

Bone Marrow Cells Can Give Rise to Ameloblast-like Cells

¹ INSERM, U595, Faculty of Medicine, 11 rue Humann, 67085 Strasbourg, France;
² Faculty of Dentistry, Louis Pasteur University, 67085 Strasbourg Cedex, France;
³ Molecular Laboratory for Gene Therapy, Faculty of Stomatology, Capital University of Medical Sciences, 4 Tian Tan Xi Li, Beijing, 100050, PR China; and
⁴ Department of Cell Biology and Histology, Faculty of Medicine and Dentistry, University of the Basque Country, Leioa 48940, Vizcaya, Spain

Correspondence: ^* corresponding authors, songlinwang{at}dentist.org.cn and Herve.Lesot{at}odonto-ulp.u-strasbg.fr

	ABSTRACT

TOP ABSTRACT INTRODUCTION MATERIALS & METHODS RESULTS DISCUSSION REFERENCES

 
Post-eruptive loss of ameloblasts requires identification of alternative sources for these cells to realize tooth-tissue-engineering strategies. Recent reports showed that bone-marrow-derived cells can give rise to different types of epithelial cells, suggesting their potential to serve as a source for ameloblasts. To investigate this potential, we mixed c-Kit⁺-enriched bone marrow cells with embryonic dental epithelial cells and cultured them in re-association with dental mesenchyme. Non-dividing, polarized, and secretory ameloblast-like cells were achieved without cell fusion. Before basement membrane reconstitution, some bone marrow cells migrated to the mesenchyme, where they exhibited morphological, molecular, and functional characteristics of odontoblasts. These results show, for the first time, that bone-marrow-derived cells can be reprogrammed to give rise to ameloblast-like cells, offering novel possibilities for tooth-tissue engineering and the study of the simultaneous differentiation of one bone marrow cell subpopulation into cells of two different embryonic lineages.

Key Words: bone marrow cells • tooth-tissue engineering • ameloblast • odontoblast

	INTRODUCTION

TOP ABSTRACT INTRODUCTION MATERIALS & METHODS RESULTS DISCUSSION REFERENCES

 
Ameloblasts disappear during tooth eruption, while enamel can be damaged due to caries, genetic diseases, or injury. Except for cultured enamel organ cells (DenBesten et al., 2005), no cell resources have yet been found to replace or regenerate ameloblasts. Although bone marrow cells have already demonstrated the potential to give rise to dental mesenchymal-like cells (Ohazama et al., 2004; Smith, 2004), their ability to give rise to ameloblast-like cells has never been tested. It has been shown that bone marrow cells contain stem cells that can give rise to various types of epithelial cells (Krause et al., 2001; Spees et al., 2003; Tran et al., 2003; Borue et al., 2004; Wang et al., 2005). A specific approach has thus been designed to investigate whether bone marrow cells might also serve as a source for ameloblasts. By using dissociation/re-association experiments (Hu et al., 2005), we re-associated crude bone marrow cells or their fractions (c-kit⁺ and c-kit^–), either alone or mixed with embryonic dental epithelial cells, with intact dental mesenchymes and cultured them in vitro. The differentiation of cells derived from bone marrow cells was analyzed according to morphological, functional, and molecular characteristics.

	MATERIALS & METHODS

TOP ABSTRACT INTRODUCTION MATERIALS & METHODS RESULTS DISCUSSION REFERENCES

 
Animals
We used 16- to 20-week-old C57BL/6-EGFP (with actin promoter/CMV enhancer to express EGFP; MARC, Nanjing, China, and IGBMC, Strasbourg, France) and CD1 (Charles River Laboratories, l’Arbresle, France) female mice for bone marrow cells. Dental tissues and cells were prepared from E14 CD1 mouse embryos. All experimental protocols were designed in compliance with the recommendation of the Beijing Experimental Animal regulation board (SYXK/JING/2005/0031) and the European Economic Community (86/609/CEE).

Cell and Tissue Preparation
Tibias and femurs were collected. Bone marrow was dissociated in Hank’s solution and filtered through a 70-µm nylon filter to yield a single cell suspension. After incubation of the low-density cells with anti-c-kit IgG microbeads, c-kit positive/negative cells were fractionated by magnetic cell sorting according to the manufacturer’s instructions (MACS, Miltenyi Biotech, Paris, France). Bone marrow cells from CD1 mice were labeled with CM-DiI (Invitrogen, Cergy Pontoise, France) according to the producer’s manual. The cell suspension was then adjusted to 5 x 10⁴ cells/mL. For each experiment, 60 first lower molars were isolated. The dental mesenchymes were dissociated from the dental epithelia as previously described (Hu et al., 2005). In one Eppendorf tube, 4 dental epithelia were dissociated into single cells in 0.5 mL culture medium, yielding 2.56 ± 0.8 x 10⁴ cells. This epithelial cell suspension (0.5 mL) was mixed with 0.5 mL of the bone marrow cell suspension and pelleted at 9000 g for 2 min. For the re-association between bone marrow cells and dental mesenchyme, 1 mL bone marrow cells was pelleted. The cell pellet was collected and re-associated with one dental mesenchyme. The culture medium and conditions were as previously described (Hu et al., 2005).

Cell Proliferation Assay
Cell proliferation was investigated as previously documented (Hu et al., 2005; for further details, see APPENDIX 1).

Immunofluorescence
We used 5-µm paraffin sections. Primary antibodies included: anti-EGFP (Abcam, Cambridge, UK), anti-cytokeratin 14 (Abcam), anti-amelogenin (L. Fisher, NIDCR, Bethesda, MD, USA), anti-MMP-20 (Santa Cruz, Heidelberg, Germany), anti-DSP (Santa Cruz), and anti-DMP-1 (Takara, Saint-Germain-en-Laye, France). Secondary antibodies were conjugated to either Alexa 594 (Invitrogen), Alexa 488 (Invitrogen), or FITC (Abcam). Nuclei were visualized by DAPI labeling (Invitrogen). The detailed conditions can be found in APPENDIX 1. The images were acquired by means of a Nikon microphot-FXA microscope (Nikon, Champigny sur Marne, France) connected to a Leica DFC 300 FX Digital Camera (Leica, Rueil-Malmaison, France) and Leica FW 4000 software. The contrast adjustment and image superimposition were done with Adobe Photoshop 7.0 for Macintosh (Adobe, Paris, France).

X and Y Chromosome Detection
The Biotin probe for the mouse X chromosome and the red whole-chromosome paint probe for the mouse Y chromosome were purchased from ID Labs (London, ON, Canada). The FISH method was performed (for further details, see APPENDIX 1). Only sections parallel to the main axes of the polarized cells were used for this study, and cells were counted on each third section so that the same nuclei would not be counted twice.

In situ Hybridization
Digoxigenin-11-UTP-labeled single-stranded RNA probes for amelogenin, ameloblastin, and Dsp/Dpp (Dr. Y. Yamada, NIDCR) were prepared with the use of a DIG RNA labeling kit (Roche Diagnostics, Barcelona, Spain) according to the manufacturer’s instructions. In situ hybridization was performed as described previously (Hirota et al., 1992). Details of the methods can be found in APPENDIX 1.

	RESULTS

TOP ABSTRACT INTRODUCTION MATERIALS & METHODS RESULTS DISCUSSION REFERENCES

 
Crude Bone Marrow Cells Rarely Give Rise to Dental Cells
Dissociated bone marrow cells obtained from C57/BL6 EGFP mice were pelleted and cultured in re-association with an E14 dental mesenchyme. In 3 independent experiments (30 samples), structured re-associations could be maintained for only 3 days before completely disorganizing as a consequence of cell spreading at the surface of the semi-solid culture medium (APPENDIX 2). Such disorganization could be avoided when bone marrow cells were mixed with dental epithelial cells at a ratio of 1:1 prior to re-association with a mesenchyme. After 20 days, a tooth crown was achieved in 30/45 samples from 3 independent experiments (Figs. 1A–1D). Since EGFP cells lost their autofluorescence soon after their engraftment in the dental epithelial and mesenchymal compartments, we used an anti-EGFP antibody to visualize them. Double immunostaining for EGFP and cytokeratin-14 showed that most EGFP bone marrow cells were located in the dental mesenchyme (Figs. 1E, 1F).

View larger version (110K): [in this window] [in a new window]   Figure 1. Cultured re-associations between dental mesenchyme and bone marrow cells mixed with dental epithelial cells. (A) Crude EGFP bone marrow cells were mixed with dental epithelial cells (1:1), re-associated with dental mesenchyme, and cultured up to 20 days. As shown after H&E staining (A), a typical dental epithelial histological organization was achieved in 30/45 samples. (B–D) In the samples illustrated in (A), anti-EGFP and anti-cytokeratin 14 (CK-14) antibodies revealed that in only 3/30 samples, bone marrow cells could be detected in the inner dental epithelium (IDE). (E,F) In the dental mesenchyme (Mes), bone marrow cells were abundant. (G) CM-DiI labeling and anti-CK-14 antibody show the engraftment of c-kit+-enriched bone marrow cells in the inner dental epithelium after 6 days. Bone marrow cells also existed in the dental mesenchyme. (H–J) Many c-kit+-enriched bone marrow cells engrafted in the inner dental epithelium and also in the dental mesenchyme after 20 days. (K-M) c-kit–-enriched bone marrow cells could be seen only rarely in the dental mesenchyme. Bar = 40 µm (A–D, H–M) and 10 µm (E–G).

c-kit⁺-enriched Bone Marrow Cells Can Acquire the Characteristics of Ameloblasts
The c-kit⁺-enriched bone marrow cells present in the inner dental epithelium were identified after being immunostained for EGFP. These cells, as observed by in situ hybridization, expressed both amelogenin (Figs. 2C, 2D) and ameloblastin (Figs. 2E, 2F), as do ameloblasts in vivo (Figs. 2A, 2B). Double-immunofluorescent staining was also performed for EGFP (Figs. 2H, 2L) and either amelogenin (Fig. 2I) or MMP-20 (Fig. 2M). The merged images show that, in the re-associations, elongated and polarized c-kit⁺-enriched bone marrow cells in the inner dental epithelium secreted amelogenin (Fig. 2J) and MMP-20 (Fig. 2N), as do ameloblasts in the teeth (Figs. 2G, 2K). The 2 proteins were also detected in the dental matrix at the epithelial-mesenchymal junction (Figs. 2I, 2J, 2M, 2N).

View larger version (107K): [in this window] [in a new window]   Figure 2. c-kit+-enriched bone marrow cells acquired characteristics of ameloblasts. (A,B) In situ hybridization for amelogenin (Amg) and ameloblastin (Amb) shows strong expression in the ameloblast (Am) layer from post-natal day 7 (P7), in the mouse first lower molar. (C,E) c-kit+-enriched bone marrow cells are present in the newly formed tooth structure from re-associations cultured for 20 days. (D,F) Superimposition of in situ hybridization for amelogenin and ameloblastin with EGFP labeling shows that c-kit+-enriched bone marrow cells engrafted in the inner dental epithelium (IDE) layer expressed the two genes. (G,K) Ameloblasts and dental matrix in the P7 mouse first lower molar were characterized by indirect immunofluorescence with antibodies to amelogenin (AMG) (G) and MMP-20 (K). (H–J) The c-kit+-enriched bone marrow cells in the ameloblast layer secreted amelogenin. (L–N) They also secreted MMP-20. (O–Q) Cultured re-association in the presence of BrdU from day 6 to day 8 shows that the engrafted c-kit+-enriched bone marrow cells in the inner dental epithelium (see Fig. 1g) still divided at this early stage. (R–T) BrdU incorporation for 48 hrs before harvesting showed that engrafted c-kit+-enriched bone marrow cells in the inner dental epithelium were no longer dividing when polarized. BrdU-labeled epithelial cells were observed only in the cervical loop (CL) region. DM, Dental Matrix; E, Enamel; Mes, Dental Mesenchyme. Bar = 40 µm (A–F, O–T) and 10 µm (G–N).

c-kit⁺-enriched Bone Marrow Cells Can Also Acquire the Characteristics of Odontoblasts
In the re-associations, the epithelial-mesenchymal junction is restored after 24 hrs (Hu et al., 2005). During the first hours of the cultures, some c-kit⁺-enriched bone marrow cells could thus migrate to the neighboring mesenchyme. They adjusted to this new micro-environment, and EGFP⁺ cells could still be detected there after 20 days (Fig. 3D). In all re-associations (n = 72), c-kit⁺-enriched bone marrow cells were observed in the layer of odontoblasts (Fig. 3D). At the epithelial-mesenchymal junction, these cells polarized and developed cell processes extending into the dental matrix (Figs. 3F, 3J). In contrast to the c-kit⁺-enriched subpopulation, only rare c-kit^– bone marrow cells were observed in the dental mesenchyme (Figs. 1K–1M). We performed in situ hybridization to search for the expression of the dentin sialoprotein/dentin phosphophoryn (Dsp/Dpp). Although the signal was slightly weaker, the c-kit⁺-enriched bone marrow cells in the odontoblast layer expressed Dsp/Dpp (Figs. 3D, 3E), as do odontoblasts in situ (Fig. 3A). Immunostaining showed that these cells could also secrete DSP (Figs. 3F–3I) and DMP-1 (Figs. 3J–3M), as do odontoblasts in situ (Figs. 3B, 3C). With optimal orientation of the sections, it was also possible to observe the characteristic shapes of odontoblasts with elongated cell processes extending into the predentin-dentin (Figs. 3J–3M). These odontoblast-like cell processes were positive for EGFP, and DMP-1 was deposited in their vicinity (Figs. 3J–3M). DSP gave weaker staining and was detected close to the odontoblast processes (Figs. 3F–3I).

View larger version (90K): [in this window] [in a new window]   Figure 3. c-kit+-enriched bone marrow cells acquired characteristics of odontoblasts. (A) Odontoblasts (Od) in the post-natal day 7 mouse first lower molar expressed Dsp/Dpp as shown by in situ hybridization. (B,C) Indirect immunofluorescence shows that they also secreted DSP (B) and DMP-1 (C) proteins. (D) In re-associations cultured for 20 days, EGFP-labeled cells derived from c-kit+-enriched bone marrow cells are detected in both epithelial and mesenchymal compartments. (E) Superimposition of Dsp/Dpp in situ hybridization with EGFP+ cells visualized in (D) shows that c-kit+-enriched bone marrow cells engrafted in the odontoblast layer expressed Dsp/Dpp. (F–I) In re-associations cultured for 20 days, the EGFP+ bone marrow cells engrafted in the odontoblast layer (G) developed cell processes (F and G, white arrows) and secreted DSP (H), which was deposited in the dental matrix (DM) between odontoblast processes (white arrows), as better visualized in the merged image (I). (J–M) These cells also secreted DMP-1 proteins. Am, Ameloblasts; CK-14, cytokeratin-14; DM, Dental Matrix; Mes, Dental Mesenchyme. Bar = 40 µm (A, D, E) and 10m (B, C, F–M).

View larger version (58K): [in this window] [in a new window]   Figure 4. c-kit+-enriched bone marrow cells gave rise to ameloblast- and odontoblast-like cells without cell fusion. (A,B) FISH for the Y chromosome (Y-chm) and staining for EGFP reveal that ameloblast-like c-kit+-enriched bone marrow cells did not have a Y chromosome, (C,D) nor did they have more than 2 X chromosomes (X-chm). (E,F) Odontoblast-like c-kit+-enriched bone marrow cells did not have a Y chromosome, (G,H) nor did they have more than 2 X chromosomes. Am, Ameloblasts; Od, Odontoblasts; Mes, Dental Mesenchyme. Bar = 10 µm.

	DISCUSSION

TOP ABSTRACT INTRODUCTION MATERIALS & METHODS RESULTS DISCUSSION REFERENCES

In contrast to c-kit^–-enriched cells, the c-kit⁺-enriched subpopulation of bone marrow cells, when mixed with dental epithelial cells, can engraft in the newly formed enamel organ. In the absence of dental epithelial cells, bone marrow cells rapidly disorganized (APPENDIX 2), suggesting that initial cell-cell adhesion is too weak but can be enhanced by dental epithelial cells. This is a prerequisite for further differentiation of bone marrow cells. The molecular support of these two steps is being investigated.

The EGFP⁺ bone marrow cells present in the inner dental epithelium shared characteristics of ameloblasts: They changed their shape, elongated, and became polarized (Smith and Nanci, 1995). These polarized cells no longer incorporated BrdU. These two steps precede the functional differentiation of ameloblasts during development. EGFP⁺ bone marrow cells in the inner dental epithelium, which expressed amelogenin and ameloblastin and secreted amelogenin as well as MMP-20, participate in amelogenesis in physiological conditions (Robinson et al., 1995; Simmer and Fincham, 1995; Fincham et al., 1999).

EGFP⁺ cells were also observed in the mesenchyme after 6 days. This suggested that some of the bone marrow cells migrated to the mesenchyme before the basement membrane was restored. Tissue-tissue re-associations have previously shown that the basement membrane was restored after 18 hrs (Osman and Ruch, 1980). It has been suggested that crude bone marrow cells can give rise to dental mesenchymal-like cells (Ohazama et al., 2004; Smith, 2004). We further show that the c-kit⁺-enriched subpopulation retains such potential. When localized at the epithelial-mesenchymal junction in the mesenchymal compartment, the EGFP⁺ cells were no longer dividing, as observed after BrdU incorporation. They also elongated and polarized, like odontoblasts (Ruch et al., 1995). The functional differentiation of these cells was assessed by in situ hybridization for Dsp/Dpp, as well as by immunostaining for DSP and DMP-1, which are major non-collagenous constituents of dentin (MacDougall et al., 1985; Butler et al., 1992; George et al., 1993). This occurred only when the c-kit⁺-enriched bone marrow cells were in contact with the epithelial-mesenchymal junction. In physiological conditions, epithelial-mesenchymal interactions mediated by the basement membrane control odontoblast differentiation (Ruch et al., 1995; Smith and Lesot, 2001). Using the c-kit^–-enriched bone marrow cell subpopulation, we observed very few EGFP⁺ cells in the dental mesenchyme, and none in the odontoblast layer. This illustrates a striking difference between the c-kit⁺- and c-kit^–-enriched subpopulations of bone marrow cells. Thus, c-kit⁺-enriched bone marrow cells might represent an alternative for the rare precursor cells of odontoblasts in the dental mesenchyme (Gronthos et al., 2000; Mina and Braut, 2004).

To explain how bone marrow cells can give rise to different cells types, two different mechanisms have been proposed: cell fusion and direct differentiation (Krause, 2005). To distinguish between these two mechanisms, investigators analyzed the sex chromosomes in the c-kit⁺-enriched bone-marrow-cell-derived ameloblast- or odontoblast-like cells (Krause et al., 2001). The results from FISH analyses show that the generation of bone-marrow-cell-derived ameloblast- and odontoblast-like cells did not involve cell fusion. Bone marrow cells might thus be used for ameloblast and odontoblast regeneration, a further step to be incorporated into a recently refined strategy for whole-tooth engineering (Hu et al., in press).

Here, we show for the first time that c-kit⁺-enriched bone marrow cells can be reprogrammed to differentiate into ameloblast- and odontoblast-like cells at the same time. The differentiation of bone-marrow-cell-derived cells correlated with their position in either the epithelium or the ecto-mesenchyme of the teeth, which developed from the re-association. It was even more precisely specified, since bone-marrow-cell-derived ameloblast-like cells were observed only in the inner dental epithelium, and bone-marrow-cell-derived odontoblast-like cells were observed only in contact with the inner dental epithelium. The system used here thus mimics the normal development of the tooth crown during development and provides a new model for study of the simultaneous differentiation of one bone marrow cell subpopulation into cells of two different embryonic lineages.

	ACKNOWLEDGMENTS

 
We thank Drs. D. Metzger and N. Jessel for EGFP mice, Dr. Y. Yamada for the amelogenin, ameloblastin, and Dsp/Dpp plasmids, Dr. L.W. Fisher for antibody to amelogenin, A. Ackerman for technical assistance, and Dr. J. Dutt for critical reading of the manuscript. This work was supported by grants from the National Natural Science Foundation of China (Grant Nos. 30125042 and 30500566), Beijing Major Scientific Program Grant, the INSERM, Louis Pasteur University, the University of the Basque Country (Grant No.1/UPV 00077.327-E-15379/2003), and the European COST B23 action.

	FOOTNOTES

 
A supplemental appendix to this article is published electronically only at http://www.dentalresearch.org.

Received for publication February 2, 2006. Revision received February 22, 2006. Accepted for publication February 27, 2006.

	REFERENCES

TOP ABSTRACT INTRODUCTION MATERIALS & METHODS RESULTS DISCUSSION REFERENCES

 

• Borue X, Lee S, Grove J, Herzog EL, Harris R, Diflo T, et al. (2004). Bone marrow-derived cells contribute to epithelial engraftment during wound healing. Am J Pathol 165:1767–1772.[Abstract/Free Full Text]
• Butler WT, Bhown M, Brunn JC, D’Souza RN, Farach-Carson MC, Happonen RP, et al. (1992). Isolation, characterization and immunolocalization of a 53-kDal dentin sialoprotein (DSP). Matrix 12:343–351.[Medline] [Order article via Infotrieve]
• DenBesten PK, Machule D, Zhang Y, Yan Q, Li W (2005). Characterization of human primary enamel organ epithelial cells in vitro. Arch Oral Biol 50:689–694.[Medline] [Order article via Infotrieve]
• Fincham AG, Moradian-Oldak J, Simmer JP (1999). The structural biology of the developing dental enamel matrix. J Struct Biol 126:270–299.[CrossRef][Medline] [Order article via Infotrieve]
• George A, Sabsay B, Simonian PA, Veis A (1993). Characterization of a novel dentin matrix acidic phosphoprotein. Implications for induction of biomineralization. J Biol Chem 268:12624–12630.[Abstract/Free Full Text]
• Gronthos S, Mankani M, Brahim J, Robey PG, Shi S (2000). Postnatal human dental pulp stem cells (DPSCs) in vitro and in vivo. Proc Natl Acad Sci USA 97:13625–13630.[Abstract/Free Full Text]
• Grove JE, Bruscia E, Krause DS (2004). Plasticity of bone marrow-derived stem cells. Stem Cells 22:487–500.[CrossRef][Medline] [Order article via Infotrieve]
• Hirota S, Ito A, Morii E, Wanaka A, Tohyama M, Kitamura Y, et al. (1992). Localization of mRNA for c-kit receptor and its ligand in the brain of adult rats: an analysis using in situ hybridization histochemistry. Brain Res Mol Brain Res 15:47–54.[Medline] [Order article via Infotrieve]
• Hu B, Nadiri A, Bopp-Kuchler S, Perrin-Schmitt F, Lesot H (2005). Dental epithelial histomorphogenesis in vitro. J Dent Res 84:521–525.
• Hu B, Nadiri A, Bopp-Kuchler S, Perrin-Schmitt F, Peters, H, Lesot H (2006). Tissue engineering of tooth crown, root and periodontium. Tissue Eng (in press).
• Krause DS (2005). Engraftment of bone marrow-derived epithelial cells. Ann NY Acad Sci 1044:117–124.[CrossRef][Medline] [Order article via Infotrieve]
• Krause DS, Theise ND, Collector MI, Henegariu O, Hwang S, Gardner R, et al. (2001). Multi-organ, multi-lineage engraftment by a single bone marrow-derived stem cell. Cell 105:369–377.[CrossRef][Medline] [Order article via Infotrieve]
• MacDougall M, Zeichner-David M, Slavkin HC (1985). Production and characterization of antibodies against murine dentine phosphoprotein. Biochem J 232:493–500.[Medline] [Order article via Infotrieve]
• Matthews W, Jordan CT, Wiegand GW, Pardoll D, Lemischka IR (1991). A receptor tyrosine kinase specific to hematopoietic stem and progenitor cell-enriched populations. Cell 65:1143–1152.[CrossRef][Medline] [Order article via Infotrieve]
• Mina M, Braut A (2004). New insight into progenitor/stem cells in dental pulp using Col1a1-GFP transgenes. Cells Tissues Organs 176:120–133.[CrossRef][Medline] [Order article via Infotrieve]
• Ohazama A, Modino SA, Miletich I, Sharpe PT (2004). Stem-cell-based tissue engineering of murine teeth (see comments). J Dent Res 83:518–522. Comment in: J Dent Res 83:517.
• Osman M, Ruch JV (1980). Secretion of basal lamina by trypsin-isolated embryonic mouse molar epithelia cultured in vitro. Dev Biol 75:467–470.[CrossRef][Medline] [Order article via Infotrieve]
• Robinson C, Kirkham J, Brookes SJ, Bonass WA, Shore RC (1995). The chemistry of enamel development. Int J Dev Biol 39:145–152.[Medline] [Order article via Infotrieve]
• Ruch JV, Lesot H, Bègue-Kirn C (1995). Odontoblast differentiation. Int J Dev Biol 39:51–68.[Medline] [Order article via Infotrieve]
• Simmer JP, Fincham AG (1995). Molecular mechanisms of dental enamel formation. Crit Rev Oral Biol Med 6:84–108.[Abstract/Free Full Text]
• Smith AJ (2004). Tooth tissue engineering and regeneration—a translational vision! [comment] J Dent Res 83:517. Comment on: J Dent Res 83:518–522.
• Smith AJ, Lesot H (2001). Induction and regulation of crown dentinogenesis: embryonic events as a template for dental tissue repair? Crit Rev Oral Biol Med 12:425–437.[Abstract/Free Full Text]
• Smith CE, Nanci A (1995). Overview of morphological changes in enamel organ cells associated with major events in amelogenesis. Int J Dev Biol 39:153–161.[Medline] [Order article via Infotrieve]
• Spees JL, Olson SD, Ylostalo J, Lynch PJ, Smith J, Perry A, et al. (2003). Differentiation, cell fusion, and nuclear fusion during ex vivo repair of epithelium by human adult stem cells from bone marrow stroma. Proc Natl Acad Sci USA 100:2397–2402.[Abstract/Free Full Text]
• Tran SD, Pillemer SR, Dutra A, Barrett AJ, Brownstein MJ, Key S, et al. (2003). Differentiation of human bone marrow-derived cells into buccal epithelial cells in vivo: a molecular analytical study. Lancet 361:1084–1088.[CrossRef][Medline] [Order article via Infotrieve]
• Wang G, Bunnell BA, Painter RG, Quiniones BC, Tom S, Lanson NA Jr, et al. (2005). Adult stem cells from bone marrow stroma differentiate into airway epithelial cells: potential therapy for cystic fibrosis. Proc Natl Acad Sci USA 102:186–191.[Abstract/Free Full Text]

Journal of Dental Research, Vol. 85, No. 5, 416-421 (2006)
DOI: 10.1177/154405910608500504


CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				G.T.-J. Huang, S. Gronthos, and S. Shi Mesenchymal Stem Cells Derived from Dental Tissues vs. Those from Other Sources: Their Biology and Role in Regenerative Medicine Journal of Dental Research, September 1, 2009; 88(9): 792 - 806. [Abstract] [Full Text] [PDF]

				S.A. Hacking and A. Khademhosseini Applications of Microscale Technologies for Regenerative Dentistry Journal of Dental Research, May 1, 2009; 88(5): 409 - 421. [Abstract] [Full Text] [PDF]

				E. Nakagawa, T. Itoh, H. Yoshie, and I. Satokata Odontogenic Potential of Post-natal Oral Mucosal Epithelium Journal of Dental Research, March 1, 2009; 88(3): 219 - 223. [Abstract] [Full Text] [PDF]

This Article Abstract Figures Only Full Text (PDF) Data Supplement Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Add to Saved Citations Download to citation manager Request Permissions Request Reprints Add to My Marked Citations Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Citing Articles via Scopus Google Scholar Articles by Hu, B. Articles by Lesot, H. Search for Related Content PubMed PubMed Citation Articles by Hu, B. Articles by Lesot, H. Social Bookmarking                         What's this?