Human dental follicle cells acquire cementoblast features under stimulation by BMP-2/-7 and enamel matrix derivatives (EMD) in vitro

Abstract

The dental follicle (DF) surrounding the developing tooth germ is an ectomesenchymal tissue composed of various cell populations derived from the cranial neural crest. Human dental follicle cells (HDFC) are believed to contain precursor cells for cementoblasts, periodontal ligament cells, and osteoblasts. Bone morphogenetic proteins (BMPs) produced by Hertwig's epithelial root sheath or present in enamel matrix derivatives (EMD) seem to be involved in the control of DF cell differentiation, but their precise function remains largely unknown. We report the immunolocalization of STRO-1 (a marker of multipotential mesenchymal progenitor cells) and BMP receptors (BMPR) in DF in vivo. In culture, HDFC co-express STRO-1/BMPR and exhibit multilineage properties. Incubation with rhBMP-2 and rhBMP-7 or EMD for 24 h increases the expression of BMP-2 and BMP-7 by HDFC. Long-term stimulation of these cells by rhBMP-2 and/or rhBMP-7 or EMD significantly increases alkaline phosphatase activity (AP) and mineralization. Expression of cementum attachment protein (CAP) and cementum protein-23 (CP-23), two putative cementoblast markers, has been detected in EMD-stimulated whole DF and in cultured HDFC stimulated with EMD or BMP-2 and BMP-7. RhNoggin, a BMP antagonist, abolishes AP activity, mineralization, and CAP/CP-23 expression in HDFC cultures and the expression of BMP-2 and BMP-7 induced by EMD. Phosphorylation of Smad-1 and MAPK is stimulated by EMD or rhBMP-2. However, rhNoggin blocks only Smad-1 phosphorylation under these conditions. Thus, EMD may activate HDFC toward the cementoblastic phenotype, an effect mainly (but not exclusively) involving both exogenous and endogenous BMP-dependent pathways.

A two-step strategy for neuronal differentiation in vitro of human dental follicle cells

“…However, less was known about neural differentiation potential of DFCs (Kemoun et al, 2007;Morsczeck et al, 2005a, b). In our study naïve DFCs strongly expressed early neural cell markers and on a low level markers for mature neural cells Corti et al, 2003;Wachs et al, 2003;Widera et al, 2007).…”

“…The surfaces of these tissues were cleaned and minced by using a sterilized scalpel. Dental follicle precursor cells were isolated as described previously (Kemoun et al, 2007;Morsczeck et al, 2005a, b). Dental follicle precursor cells were seeded into cell culture flasks in regular cell culture medium DMEM [Dubelco modified Eagle medium (with L-glutamine) supplemented with 10% fetal calf serum and penicillin/streptomycin (all purchased from PAA, Pasching, Austria] and incubated at 37 1Cin5%CO 2 in a humidified atmosphere.…”

“…In previous studies, we demonstrated that DFCs can differentiate into osteogenic cells under in vitro and in vivo conditions (Morsczeck et al, 2005a, b). Recently, Kemoun et al (2007) demonstrated that isolated dental follicle cells expressed the mesenchymal stem cell marker STRO-1. Moreover, they confirmed that follicle cells have multipotential mesenchymal precursor cell properties after differentiating toward multiple mesenchymal-derived cell types, such as cementoblasts, chondrocytes and adipocytes (Kemoun et al, 2007).…”

“…Recently, Kemoun et al (2007) demonstrated that isolated dental follicle cells expressed the mesenchymal stem cell marker STRO-1. Moreover, they confirmed that follicle cells have multipotential mesenchymal precursor cell properties after differentiating toward multiple mesenchymal-derived cell types, such as cementoblasts, chondrocytes and adipocytes (Kemoun et al, 2007). However, they did not demonstrate neural cell differentiation potential for dental follicle cells.…”

The Transcription Factor DLX3 Regulates the Osteogenic Differentiation of Human Dental Follicle Precursor Cells

“…These cells are multipotent and can be differentiated, for example, into adipocytes, chondrocytes, and neural cells [2][3][4]. Although molecular mechanisms in DFCs are not yet completely understood, the differentiation and function of dental follicular cells are known to be controlled by a network of regulatory molecules including transcription factors, growth factors, and cytokines [5,6].…”