Immortalization and characterization of human dental pulp cells with odontoblastic differentiation.
OBJECTIVE
To immortalize human dental pulp (HDP) cell showing stable growth and high mineralization activities in vitro.


METHODS
HDP cells were obtained from a healthy third molar and immortalized by transfection with human telomerase transcriptase (hTERT) gene. To examine the characters of hTERT transfected HDP (HDP-hTERT) cells, we examined expression of mRNA for dentin sialophosphoprotein (DSSP), type I collagen (COLI), alkaline phosphatase (ALP) and bone sialoprotein (BSP) by RT-PCR. In addition, we examined ALP activity by biochemical method and nodule formation by alizarin red S (ALZ) staining.


RESULTS
HDP-hTERT was obtained by transfection with hTERT gene. These cells bypassed the senescence and grew over 120 population doublings (PDLs) without significant growth retardation. High expression of hTERT was confirmed in HDP-hTERT by RT-PCR and showed remarkable telomerase activity. Both HDP-original (HDP-ori) and HDP-hTERT expressed DSSP, COLI, ALP and BSP mRNA and showed ALP activity and ALZ staining at the same levels.


CONCLUSIONS
We were able to establish a cell line of immortalized human dental pulp cells with odontoblastic differentiation which will be a useful cell model for studying the mechanism of proliferation and differentiation of odontoblasts.
Kitagawa
Masae
M
Department of Oral and Maxillofacial Pathobiology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
Ueda
Hirota
H
Iizuka
Sinji
S
Sakamoto
Kiyako
K
Oka
Hiroko
H
Kudo
Yasusei
Y
Ogawa
Ikuko
I
Miyauchi
Mutsumi
M
Tahara
Hidetoshi
H
Takata
Takashi
T
D000469:Alkaline Phosphatase / Q000032:analysis; D000880:Anthraquinones; D015415:Biomarkers / Q000032:analysis; D002454:Cell Differentiation / Q000235:genetics; D002461:Cell Line, Transformed; D049109:Cell Proliferation; D024042:Collagen Type I / Q000032:analysis; D004396:Coloring Agents; D003782:Dental Pulp / Q000166:cytology*; D016326:Extracellular Matrix Proteins / Q000032:analysis; D005822:Genetic Vectors / Q000235:genetics; D006801:Humans; D058574:Integrin-Binding Sialoprotein; D009804:Odontoblasts / Q000166:cytology*; D010750:Phosphoproteins / Q000032:analysis; D012190:Retroviridae / Q000235:genetics; D012795:Sialoglycoproteins / Q000032:analysis; D019098:Telomerase / Q000235:genetics; D014162:Transfection / Q000379:methods; D014170:Transformation, Genetic / Q000235:genetics*; D000099311:Dentin Sialophosphoprotein
D000469:Alkaline Phosphatase; D000880:Anthraquinones; D015415:Biomarkers; D024042:Collagen Type I; D004396:Coloring Agents; D016326:Extracellular Matrix Proteins; D058574:Integrin-Binding Sialoprotein; D010750:Phosphoproteins; D012795:Sialoglycoproteins; D019098:Telomerase; D000099311:Dentin Sialophosphoprotein; C546871:IBSP protein, human; C004468:Alizarin Red S; C509186:TERT protein, human