Transcriptome of human odontoblast, pre-secretory ameloblast and secretory ameloblast

The goal of the study was to characterize the whole genome transcriptome profiles of human ameloblasts and odontoblasts, evaluate molecular pathways and advance our knowledge of the human tooth development. We found that during primary tooth formation, odontoblasts expressed 14,802 genes, presecretory ameloblasts 15,179 genes and secretory ameloblasts 14,526 genes. Four human fetuses were obtained at ages 15-20 weeks gestation, immediately placed on ice and the tooth buds dissected from the jaws, placed in RNAlater and refrigerated at 4C for 1-4 weeks to allow decalcification by EDTA. The tissue was then frozen and stored at -80C. The tissue was sectioned at -35C at a thickness of 7 microns. These sections were used for laser capture microdissection (LCM) to isolate the human odontoblasts and ameloblasts in different stages of enamel formation, using static image settings. In total, 4 odontoblast, 4 pre-secretory ameloblast and 4 secretory ameloblast pooled samples were used for RNA extraction and microarray analysis.