title: Directing the differentiation of human dental follicle cells into cementoblasts and/or osteoblasts by a combination of HERS and pulp cells.
abstract: It is known that the dental follicle (DF) consists of progenitor cells that give rise to the cementum, periodontal ligament, and alveolar bone; but little information is available about the regulation of DF cell differentiation into either cementogenic or osteogenic cell lineages for the regeneration of diseased periodontal tissue. Here, we investigated the roles of DF, Hertwig's epithelial root sheath (HERS), and pulp cells in the cementum and during alveolar bone formation. We cultured these cells; transplanted them alone or in combination into immunocompromised mice; and observed their effects at 6 and 12 weeks. Histological and immunohistochemical results revealed that DF cells formed cementum-like tissues with immunoreactivity to cementum-derived attached protein, bone sialoprotein, type I collagen, and alkaline phosphatase. In addition, HERS cells played a role in the induction and maturation of cementum-like tissues formed by DF cells. In contrast, implants of DF cells in the presence of pulp cells led to the formation of bone-like tissues. Interestingly, in the presence of both HERS and pulp cells, DF cells formed both cementum-like and bone-like tissues. We demonstrated that while HERS cells are able to induce DF cell differentiation into cementoblasts and promote cementum formation, pulp cells could direct DF cell differentiation into osteoblasts and enhance alveolar bone formation. These results suggest that the combined use of DF, HERS, and pulp cells could direct DF cell differentiation into cementoblasts and/or osteoblasts in vivo, thus providing a novel strategy for the successful repair and regeneration of diseased periodontal tissue.
authors.affiliation: Department of Oral Histology-Developmental Biology and Dental Research Institute, BK21 Project, School of Dentistry, Seoul National University, 28 Yeongun-Dong, Chongro-Gu, Seoul #110-749, Korea.
authors.forename: Hyun-Sung
authors.initials: HS
authors.lastname: Jung
authors.forename: Dong-Seol
authors.initials: DS
authors.lastname: Lee
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Lee
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Park
authors.forename: Gene
authors.initials: G
authors.lastname: Lee
authors.forename: Byoung-Moo
authors.initials: BM
authors.lastname: Seo
authors.forename: Jea Seung
authors.initials: JS
authors.lastname: Ko
authors.forename: Joo-Cheol
authors.initials: JC
authors.lastname: Park
mesh_terms: D000293:Adolescent; D020087:Alu Elements / Q000235:genetics; D002454:Cell Differentiation; D017690:Cell Transplantation; D002478:Cells, Cultured; D025021:Cementogenesis / Q000502:physiology; D003739:Dental Cementum / Q000166:cytology* / Q000502:physiology; D003782:Dental Pulp / Q000166:cytology*; D003795:Dental Sac / Q000166:cytology*; D006801:Humans; D010006:Osteoblasts / Q000166:cytology*; D010641:Phenotype; D012038:Regeneration; D014092:Tooth Root / Q000166:cytology*