Temperature Sensitive Simian Virus 40 Large T Antigen Immortalization of Murine Odontoblast Cell Cultures: Establishment of Clonal Odontoblast Cell Line

During tooth formation instructive epithelial-mesenchymal interactions result in the cytodifferentiation of ectomesenchy-mal cells into odontoblasts which produce the dentin extracellular matrix (DECM). The purpose of our study was to establish a stable murine odontoblast cell line by immortalization of odontoblasts using retrovirus transfection. In order to accomplish this goal, we utilized a previously characterized odontoblast monolayer cell culture system supportive of odontoblast cytodifferentiation from dental papilla mesenchyme (DPM), expression and secretion of a DECM and dentin biomineralization. First mandibular molars from E-18 Swiss Webster mice were dissected, the DPM isolated, and pulp cells dissociated. Pulp cells (5 × 105well) were plated as monolayers and grown in α-MEM supplemented with 10% FCS, 100 units/ml penicillin and streptomycin, 50 μg/ml ascorbic acid. Cultures were maintained for 6 days at 37°C in a humidified atmosphere of 95% air and 5% CO2 with media changes every two days. I...