Molecular differences between stromal cell populations from deciduous and permanent human teeth.

Abstract

IntroductionDeciduous and permanent human teeth represent an excellent model system to study aging of stromal populations. Aging is tightly connected to self-renewal and proliferation and thus, mapping potential molecular differences in these characteristics between populations constitutes an important task.MethodsUsing specifically designed microarray panels, Real-Time Quantitative Polymerase Chain Reaction (RT q-PCR), Western blot, immunohistochemistry and siRNA-mediated knock down experiments, we have detected a number of molecules that were differentially expressed in dental pulp from deciduous and permanent teeth extracted from young children and adults, respectively.ResultsAmong the differentially regulated genes, high-mobility group AT-hook 2 (HMGA2), a stem cell-associated marker, stood out as a remarkable example with a robust expression in deciduous pulp cells. siRNA-mediated knock down of HMGA2 expression in cultured deciduous pulp cells caused a down-regulated expression of the pluripotency marker NANOG. This finding indicates that HMGA2 is a pulpal stem cell regulatory factor. In addition to this, we discovered that several proliferation-related genes, including CDC2A and CDK4, were up-regulated in deciduous pulp cells, while matrix genes COL1A1, fibronectin and several signaling molecules, such as VEGF, FGFr-1 and IGFr-1 were up-regulated in the pulp cells from permanent teeth.ConclusionsTaken together, our data suggest that deciduous pulp cells are more robust in self- renewal and proliferation, whereas adult dental pulp cells are more capable of signaling and matrix synthesis.Electronic supplementary materialThe online version of this article (doi:10.1186/s13287-015-0056-7) contains supplementary material, which is available to authorized users.