Immortalization and characterization of human dental papilla cells with odontoblastic differentiation

Abstract

Aim: To establish a cell line of immortalized human dental papilla cells (hDPCs). Methodology: Primary hDPCs were cultured and infected with lentivirus containing the hTERT gene. Integration and transcription of the hTERT gene were verified by PCR. The characteristics of the cells, such as morphology, proliferation and mineralization, were analysed. Also, the expression of odontoblastic-related markers including ALP, DMP1, DLX3, OSX, DSP and Nestin, was detected by immunohistochemistry and real-time RT-PCR. Results: hTERT gene was integrated into genomic DNA of immortalized cells (hDPC-TERT) and transcribed into mRNA. With long-time culture, hDPC-TERT bypassed senescence and grew over 120 population doublings. hDPC-TERT cells have a higher proliferation rate, but retain the phenotypic characteristics of the primary hDPCs, and so was ALP activity and mineralization activity. Furthermore, the hDPC-TERT cells express no DSP and Nestin with maintenance medium, but highly expressed DSP and Nestin after odontoblastic induction. Conclusions: A line of immortalized human dental papilla cells, which remains in an undifferentiated state and has odontoblastic differentiation potential, was established. This cell line can be used as a cell model for studying the mechanism of the initiation of odontoblast differentiation. © 2012 International Endodontic Journal.