Expression of NOD2 in Human Dental Pulp Cells and Tissue

Nucleotide-binding oligomerization domain(NOD) proteins are important factors in innate immune responses because they mediate signals from bacterial cell wall components during immune reactions. However, the role of NOD proteins in dental pulp is little understood.

Objective:The purpose of the study was to determine the expression of NOD2 in normal human dental pulp cells and the dental pulp tissue.

Methods:Human dental pulp cells were prepared from the explants of normal human dental pulp tissues and pulp tissues were collected from freshly extracted human wisdom teeth.Nest reverse transcription-polymerase chain reaction and Western blotting were performed to detect NOD2 mRNA and protein expression respectively. Immunohistochemical staining was used to determine the distribution of NOD2 in normal human dental pulp tissue.

Results:It was demonstrated that NOD2 mRNA and protein expressions were notably present in normal human dental pulp tissues and that NOD2 protein expression was mainly distributed in odontoblasts and some pulpal vascular endothelial cells. In contrast, human dental pulp cells only presented low expression of NOD2 protein. Moreover, the expression of NOD2 mRNA can not be detected in human dental pulp cells in our study.

Conclusion:These findings suggest that NOD2 protein expressed in human dental pulp cells and tissue may play an important role in the dental immune defense.