Tissue and Cell 39 (2007) 257–266
Localization of STRO-1, BMP-2/-3/-7, BMP receptors and
phosphorylated Smad-1 during the formation of mouse periodontium
P. K
´
emoun
a,b,c
, S. Laurencin-Dalicieux
a,b,c
,J.Rue
a,b
, F. Vaysse
b,d
,A.Rom
´
eas
e
,
H. Arzate
f
, F. Conte-Auriol
c,g
, J.C. Farges
e
, J.P. Salles
b,c,g
, G. Brunel
a,b,∗
a
Department of Oral Biology, Faculty of Odontology, 3 chemin des Maraˆıchers, 31062 Toulouse Cedex, France
b
Universit´e Toulouse III Paul-Sabatier, Toulouse F-31400, France
c
INSERM, U563, Centre de Physiopathologie de Toulouse Purpan, Toulouse F-31300, France
d
Department of Pedodontics, Faculty of Odontology, 3 chemin des Maraˆıchers, 31062 Toulouse, France
e
Laboratory “Development and Regeneration of Dental Tissues”, INSERM ERI16, EA 1892, IFR62, Faculty of Odontology,
University Lyon1, Rue Guillaume Paradin, 69372 LYON Cedex 08, France
f
Laboratorio de Biologia Cellular y Molecular, Faculdad de odontologia, UNAM, Ciudad Univeristaria, Coyoacan 04510 DF, Mexico
g
CHU Toulouse, Unit´e d’Endocrinologie Maladies Osseuses, Hˆopital des Enfants, CHU de Toulouse F-31300, France
Available online 26 July 2007
Abstract
Bone morphogenetic proteins (BMPs) and BMP receptors (BMPRs) are known to regulate the development of calcified tissues by directing
mesenchymal precursor cells differentiation. However, their role in the formation of tooth-supporting tissues remains unclear. We investigated
the distribution pattern of STRO-1, a marker of mesenchymal progenitor cells and several members of the BMP pathway during the development
of mouse molar periodontium, from the post-natal days 6 to 23 (D6 to D23). STRO-1 was mainly localized in the dental follicle (DF) at
D6 and 13 then in the periodontal ligament (PDL) at D23. BMP-2 and -7 were detected in Hertwig’s epithelial root sheath (HERS) and in
DF, then later in differentiated periodontal cells. BMP-3 was detected after D13 of the periodontal development. BMPRs-Ib, -II, the activin
receptor-1 (ActR-1) and the phosphorylated Smad1 were detected in DF and HERS at D6 and later more diffusely in the periodontium.
BMPR-Ia detection was restricted to alveolar bone. These findings were in agreement with others data obtained with mouse immortalized DF
cells. These results suggest that STRO-1 positive DF cells may be target of BMPs secreted by HERS. BMP-3 might be involved in the arrest
of this process by inhibiting the signaling provided by cementogenic and osteogenic BMPs.
© 2007 Elsevier Ltd. All rights reserved.
Keywords: Bone morphogenetic protein; Mesenchymal cells; Precursor cells; Hertwig’s epithelial root sheath; Dental follicle
1. Introduction
Mesenchymal cell precursors with multipotential proper-
ties have been localized in the periodontal ligament (PDL)
in humans (Seo et al., 2004). These cells express STRO-1, a
cell surface antigen characteristic of mesenchymal progeni-
tor cells present in bone marrow (Simmons et al., 1994) and
may differentiate into highly specialized periodontal cells
(Seo et al., 2004). The dental follicle (DF) surrounding the
∗
Corresponding author at: Department of Oral Biology, Faculty of Odon-
tology, Paul Sabatier University, 3 chemin des Mara
ˆ
ıchers, 31062 Toulouse
Cedex, France. Tel.: +33 5 62 17 36 09; fax: +33 5 61 25 47 19.
E-mail address: brunel@cict.fr (G. Brunel).
developing tooth germ is an ectomesenchymal tissue com-
posed of heterogeneous cell populations derived from the
cranial neural crest which also include periodontal precur-
sors (Morsczeck et al., 2005; Ivanovski et al., 2006; K
´
emoun
et al., 2007). Although their capacity to differentiate into vari-
ous cell types including osteoblasts and/or cementoblasts has
also been demonstrated (Hakki et al., 2001; Zhao et al., 2002;
Luan et al., 2006), expression of STRO-1 by mouse DF cells
has never been investigated.
Bone morphogenetic proteins (BMPs) are involved in the
development of numerous skeletal and extra-skeletal organs
and tissues in vertebrates (Chen et al., 2004). BMP-2 and
-7 induce rodent mesenchymal cells to differentiate into
osteoblasts (Zhu et al., 2004), while BMP-3 down-regulates
0040-8166/$ – see front matter © 2007 Elsevier Ltd. All rights reserved.
doi:10.1016/j.tice.2007.06.001