[Frontiers in Bioscience E4, 1009-1014, January 1, 2012]

Stromal phenotype of dental follicle stem cells

Francesca Angiero1, Carlo Rossi2, Angelita Ferri1, Rossella Seramondi2, Sarah Magistro2, Davide Farronato2, Stefano Benedicenti3, Giampietro Farronato2, Milena Fini4, Angelo Carpi5, Giorgio Cattoretti1

1Department of Pathology, S. Gerardo Hospital, University of Milan-Bicocca, Italy, 2Department of Orthodontics, The University of Milan, Italy, 3Department of Stomalogical Science, S. Martino Hospital, University of Genoa, Italy, 4Laboratory of preclinical and surgical studies Rizzoli Orthopedic Institute, 5University of Pisa, Italy, Italy

TABLE OF CONTENTS

1. Abstract
2. Introduction
3. Materials and Methods
3.1.Patients and Design
3.2. Immunohistochemical Methods
3.3.Cell counting
4. Results
5. Discussion
6. Acknowledgement
7. References

1. ABSTRACT

It has been suggested that stem/progenitor cells exist in dental tissue. This study identified adult mesenchymal stem/stromal cell-like populations in the dental follicle of human impacted third molars.The immunohistochemical analysis, of dental follicle using known stem-cell markers: Cytokeratins (AE1-AE3), Smooth Muscle Actin, Ki-67, CD34, CD44, CD45, CD56, and CD133. A positive reaction for at least one of the markers typical of stromal phenotype (CD56, CD44 and CD271) was observed in seven cases . Interestingly, all positive cases showed coexpression of CD44 and CD56, except for one case which was CD56 positive and CD44 negative. Immunohistochemical reaction was negative in all 27 cases for Ki-67, Cytokeratins, Smooth Muscle Actin, CD34, CD133 and CD45. The association: negative for CD34, CD45, CD133, and positive for CD44, CD56 (markers of a subpopulation of stem cells from bone marrow) suggests these may be quiescent mesenchymal stem cells, a hypothesis supported by the negativity of Ki-67 (proliferative index). Our results are compatible with the identification of immature fibroblast cells with phenotypic features of stromal stem cells in the dental follicle.