Expression Pattern Of Rad54b In Odontoblastic Differentiation And Reparative Dentinogenesis

To investigate the expression pattern of RAD54B, a homologous recombination accessory factor, in odontoblastic differentiation and reparative dentinogenesis and explore its role in the odontoblastic differentiation of human dental pulp stem cells (hDPSCs). Animal experiments were performed in accordance with the guidelines of the Animal Ethics Committee. Mandibles of PN2.5 mice (C57BL/6, n=6) were collected, and Rad54b expression was assessed via immunohistochemistry. A wild-type mouse model for reparative dentinogenesis (C57BL/6, 7-8 weeks, n=6/group) was established, and maxillae were collected at 0, 12, 72 hours, 7 days, and 14 days post-surgery. Histological assays, including H&E, TUNEL, Nestin/α-SMA double immunofluorescence, and Rad54b immunohistochemistry, were performed. For in vitro studies, hDPSCs were induced to differentiate into odontoblast-like cells, and mRNA levels of DSPP, DMP1, NES, and RAD54B were measured by RT-qPCR. RAD54B knockdown was achieved in hDPSCs via siRNA transfection, and Western blotting and ALP staining were used to assess the protein levels and odontoblastic differentiation capacity. Rad54b expression was significantly higher in odontoblasts compared to undifferentiated cells in PN2.5 incisors and molars. During reparative dentinogenesis, Rad54b exhibited a dynamic expression pattern in conjunction with the differentiation of dental pulp stem cells into odontoblast-like cells. RAD54B was upregulated during odontoblastic differentiation of hDPSCs, and its knockdown impaired ALP activity and odontoblast marker expressions. RAD54B may play a critical role in odontoblastic differentiation and reparative dentinogenesis.